Nucleophilic Ring Opening of Donor-Acceptor ... - ACS Publications

A pilot experiment with a Lewis acid, MgBr2·OEt2, produced a mixture of unidentified products (entry 10). Consequently, the heating of 1a, KNCO (2 eq...
0 downloads 0 Views 751KB Size
Subscriber access provided by University of Sussex Library

Note

Nucleophilic Ring Opening of Donor-Acceptor Cyclopropanes with the Cyanate Ion: Access to Spiro[pyrrolidone-3,3’-oxindoles] Sergey V. Zaytsev, Konstantin L. Ivanov, Dmitry A. Skvortsov, Stanislav I. Bezzubov, Mikhail Ya. Melnikov, and Ekaterina M. Budynina J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.8b00922 • Publication Date (Web): 12 Jun 2018 Downloaded from http://pubs.acs.org on June 12, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Nucleophilic Ring Opening of Donor–Acceptor Cyclopropanes with the Cyanate Ion: Access to Spiro[pyrrolidone-3,3’-oxindoles] Sergey V. Zaytsev,† Konstantin L. Ivanov,† Dmitry A. Skvortsov,† Stanislav I. Bezzubov,‡ Mikhail Ya. Melnikov,† and Ekaterina M. Budynina*† †

Department of Chemistry, Lomonosov Moscow State University, Leninskie gory 1-3, Moscow

119991 Russia ‡

Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences,

Leninskiy pr. 31, Moscow 119991 Russia

ABSTRACT: The nucleophilic ring opening of donor-acceptor cyclopropanes with the cyanate ion is reported for the first time. Cyclopropanes, spiroactivated with oxindole fragments as acceptors, are shown to undergo transformations into biologically relevant spiro[pyrrolidone3,3′-oxindoles] while being treated with potassium cyanate under microwave assistance. The strain-driven ring opening of donor-acceptor (DA) cyclopropanes1 with nucleophiles is of great importance as a simple stereocontrolled pathway towards 1,3-functionalized compounds.2 In a broad range of nucleophiles studied as initiators of DA cyclopropane ring opening, Nnucleophiles are of particular significance since they provide numerous opportunities to synthesize structurally diverse N-containing molecules, especially the most privileged and significant N-heterocycles.3 Most N-nucleophiles that were investigated in reactions with DA cyclopropanes are organic compounds, such as amines,4 hydrazines,5 amides,6 nitriles,7 and Nheterocycles8 (Scheme 1, a). Among inorganic salts, only sodium azide was systematically studied in DA cyclopropane ring opening towards the synthesis of functionalized organic azides and, subsequently, N-heterocycles.9 Our previous study revealed that, in general, nucleophilic ring opening of commonly used 2-arylcyclopropane-1,1-diesters, triggered by an SN2-like attack of the azide ion, proceeded under prolonged heating at 100 °C.9b In this regard, less reactive nucleophiles can require more demanding conditions, additionally activating undesired side processes that invalidate the utility of the target reaction. Despite these challenges, we attempted ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

to design a new type of a nucleophilic ring opening of DA cyclopropanes with the cyanate ion, which is isoelectronic to the azide ion (Scheme 1, b). Among DA cyclopropanes of several subclasses, cyclopropanes 1 spiro-activated with the oxindole were found to tolerate severe reaction conditions. The discovered reaction allowed for a new rapid access to spiro[pyrrolidone3,3’-oxindoles] 2, which are representatives of a large family of biologically relevant spiro[pyrrolidine-3,3’-oxindoles] (Scheme 1, c).10 Scheme 1. The Strategy of This Work a. N-nucleophiles for DA cyclopropane ring opening Organic amines

EWG

amides

EWG

hydrazines nitriles

N-heterocycles

N N

Inorganic

EDG

M+N3previous work

M+NCO this work

EDG

EWG - electron-withdrawing group EDG - electron-donating group b. General concept: Ring openings with pseudohalide anions

N3

NCO

EDG EDG

EWG N

N

N

EWG

SN2-like TS

EDG

EWG N

C

O then cyclization / protonation

then protonation

c. This work: Ring opening of spiro[cyclopropane-1,3'-oxindoles] with NCO H

N

R" O

R N R'

1

KNCO Et3N—HCl 150 C

R"

O O

R N R'

2

Spontaneous assembly of the pyrrolidone unit in 2 should be obvious when accounting for intermediate formation of acyclic isocyanate with an anionic center stabilized with EWG (Scheme 1, b). Therefore, this process can be compared with (3+2)-cycloadditions and related reactions between DA cyclopropanes and isocyanates as well as their thio-analogs (Scheme 2). As early as late 1980s, Graziano and co-workers demonstrated that (3+2)-cycloadditions of dialkoxy-activated DA cyclopropanes to iso(thio)cyanates provided formation of γ(thio)lactams.11 Reissig et al. carried out related process with cyclopropyl anions yielding pyrroline derivatives.12 At the same time, Tsuji et al. revealed similar reactivity for vinylsubstituted DA cyclopropanes when activated with Pd(0)-catalysts.13 Recently, Stoltz and coworkers reported analogous (3+2)-cycloaddition between isocyanates and aryl-substituted DA cyclopropanes,14 which are being intensively studied in the recent years. More relevant example of this reaction with spirocyclopropaneoxindole being used was reported by Marti and Carreira.15

ACS Paragon Plus Environment

Page 2 of 42

Page 3 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Scheme 2. Pyrrolidine Core Formation via Reactions of DA Cyclopropanes with Iso(thio)cyanates

Our initial attempts were directed towards determining reaction conditions for the chemoselective nucleophilic ring opening and, thus, were related to the screening of starting DA cyclopropanes with appropriate donor (EDG) and acceptor (EWG) activating groups tolerant to these conditions. First, we examined common dimethyl 2-phenylcyclopropane-1,1-diester which was treated with KNCO in DMF at several temperatures. Its visible conversion was detected starting from 140 °C. However, Krapcho dealkoxycarbonylation was found to be the main process (also caused by a nucleophilic attack but on the ester group). Since nucleophilic ring opening of DA cyclopropanes with N3- was proved to be a reversible step, requiring an H+ source to complete the reaction, we checked whether protic additives influenced the reaction of 2phenylcyclopropane-1,1-diester with NCO- as well. We found that the presence of Et3N⋅HCl did not allow for reducing the temperature of the reaction, ultimately leading to significant tarring along with detectable lactonization. The obtained results are in agreement with those reported by Kerr and co-workers and related to lactonization of cyclopropanes proceeding presumably via SN2-like ring opening with the chloride ion.16 Therefore, for the ester-substituted DA cyclopropanes, lactonization and dealkoxycarbonylation are more preferable under the studied

ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

conditions, while the tendency of such cyclopropanes to undergo ring opening with NCO- is much lower than that for the isoelectronic N3-. We recently revealed that the SN2-like ring opening of DA cyclopropanes with N3- is a convenient model to estimate their relative reactivity.9b According to this model, 2phenylcyclopropane-1,1-dinitrile is more reactive than the diester analogue. However, its reaction with NCO- led only products of oligomerization. In this regard, we recognized that two key conditions should be satisfied. First, cyclopropane should not be functionalized with EWG prone to participate in Cloke-type ring enlargements17 or reactions with nucleophiles, e.g., Krapcho dealkoxycarbonylation. Second, the use of EWG with lower acceptor properties requires additional activation of the DA cyclopropane. Since one of the common tricks for this is spiro-activation,18 we examined cyclopropanes 1 spiro-activated with oxindole as an EWG in reaction with NCO-, giving priority to biologically relevant structures. Recently, similar cyclopropanes were found to exhibit reactivity against N3- that was comparable to arylcyclopropane-1,1-diesters.9a Our initial experiments displayed that, despite significant tarring, the reaction of cyclopropane 1a with KNCO in DMF at 150 °C indeed resulted in the product of nucleophilic ring opening/cyclization 2a in 20 and 50% yields for conventional and microwave heating, respectively (Table 1, entries 1,2). Due to the demonstrated superiority of microwave heating, further optimization was carried out under microwave assistance. Further study revealed that only 85% conversion of 1a could be achieved, regardless of duration of heating and extra amounts of KNCO. Suspecting poor solubility of KNCO under studied conditions, we carried out experiments with 18-crown-6 (entries 3-5); however, only modest yields of 2a were obtained at incomplete conversions of 1a, along with further drops in 2a yields at additional heating. Varying solvents and reaction temperatures did not provide enhancements in 2a yield (entries 47). Since the obtained results pointed to reversibility, we carried out the reactions in the presence of Et3N⋅HCl (entries 8,9) which would protonate the intermediate anion A. Due to high probability of KNCO decomposition under the studied conditions, an extra amount of KNCO was added in 4 h after initiation. In this case, reaction afforded a 96% conversion of 1a and a 62% isolated yield of 2a (entry 9). A pilot experiment with a Lewis acid, MgBr2·OEt2, produced a mixture of unidentified products (entry 10). Consequently, the heating of 1a, KNCO (2 equiv) and Et3N·HCl (1 equiv) in DMF at 150°C (with extra amount of KNCO (2 equiv) in 4 h after initiation) was considered optimal for nucleophilic ring opening of 1a with NCO- (entry 9). Table 1. Optimization of the Reaction Conditions

ACS Paragon Plus Environment

Page 4 of 42

Page 5 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Entry

Solvent

Additive (equiv)

t (h)

T (°C)a

Yield (%)b

1

DMF



9.5

150c

20

2

DMF



7

150

50d

3

DMF

18-crown-6 (2)

1.5

150

56d

4

NMP

18-crown-6 (2)

1.5

170

55d

5

DMSO

18-crown-6 (2)

1

170

25

6

DMF



3

130

46

7

DMSO



4

150c

trace

8

DMF

Et3N·HCl (1)

7

150

42

150

62

130

–f

9

DMF

Et3N·HCl (1)

10

10

THF

MgBr2⋅OEt2 (1)

3

e

a Microwave heating. bNMR yield. cConventional heating. dIsolated yield. eAn extra portion of KNCO (2 equiv) was added in 4 h. fA mixture of unidentified products.

Under the optimized conditions, spiro[cyclopropane-1,3’-oxindoles] 1 were examined to assess compatibilities of substituents in spirooxindole and cyclopropane units (Scheme 3). A series of N-PMB-substituted cyclopropanes 1b-j (PMB = para-methoxybenzyl), containing both donor and acceptor groups in the cyclopropane aryl fragment, generally provided products 2b-i in good yields, despite harsh reaction conditions. Cyclopropanes 1b,c,i,j, containing electron-abundant aryls, as well as their counterparts 1d,e with electron-deficient aryls, underwent nucleophilic ring opening with NCO- more efficiently (3–6 h) than their phenyl analog 1a (10 h). The exception is para-NO2-substituted cyclopropane 1f which did not produce the corresponding product 2f undergoing complete decomposition in 2 h instead. α-Naphthyl derivative 1h was the slowest to react, due to the ortho-bulkiness affecting the kinetics unfavourably. Its complete conversion was observed in 16 h, leading to significant tarring and, thus, decreasing isolated yield of 2h down to 34%. 2-Thienyl derivative 1k was also sufficiently tolerant towards harsh reaction conditions, affording 2k in 3 h with a 56% yield. The introduction of substituents in the benzene core of the oxindole moiety allowed for more significant manipulations of the reaction rate. Although 5-methyl derivative 1l underwent ring opening by NCO- with a rate similar to that for 1a, complete conversions of 5-halogen derivatives 1m-p were achieved in 100-120 min. Competitive reactions of two cyclopropanes 1l and 1p with KNCO allowed us to reveal that for 90 min, 95% conversion of Br-derivative 1p ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

was achieved, whereas Me-derivative 1l exhibited only 18% conversion. This tendency is in accordance with results of our DFT calculations of SN2-like ring opening of 1 with NCO-: the replacement of H or Me by halogens leads to lowering of the corresponding energy barriers.19 Replacing the N-PMB group with a Me one (1q-u) did not influence the reaction times and the yields of the products 2q-u. The structure of 2r was unambiguously proved by single crystal Xray analysis. Scheme 3. Reaction Scope

The combination of N-unprotected pyrrolidone and N-protected oxindole units in 2 allows for selective protection/deprotection of both cyclic amides. The presence of PMB N-protecting group in oxindole allowed for the deprotection of 2,20 producing doubly N-unprotected spiro[pyrrolidone-3,3’-oxindoles] 3 (Scheme 4). The evolution of 2 can also be related to their selective reduction into the corresponding pyrrolidines.21

ACS Paragon Plus Environment

Page 6 of 42

Page 7 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Scheme 4. N-deprotection of PMB Derivatives 2a,i,o

Preliminary in vitro tests of compounds 2 and 3 revealed their moderate antiproliferative activity towards HEK293T, MCF7 and A549 cell lines.19 In conclusion, we have demonstrated the use of the cyanate ion as a new N-nucleophile for DA cyclopropane ring opening. In comparison with the isoelectronic azide ion, the cyanate ion was found to be less reactive toward small ring opening that required a delicate tradeoff between harsh reaction conditions and DA cyclopropane reactivity. Based on the obtained results, a method for nucleophilic ring opening of DA cyclopropanes, spiro-activated with oxindole, with the cyanate ion was developed. A series of cyclopropanes containing various substituents in the oxindole and cyclopropane units exhibited good tolerance toward reaction conditions, ultimately affording spiro[pyrrolidone-3,3’-oxindoles] with N-unprotected pyrrolidone unit. EXPERIMENTAL SECTION

General information NMR spectra were acquired either on Bruker Avance 400 MHz or on Bruker Avance 600 MHz spectrometers at room temperature; the chemical shifts δ were measured in ppm with respect to solvent (1Н: CDCl3, δ = 7.27 ppm, DMSO-d6, δ = 2.50 ppm; 13C: CDCl3, δ = 77.0 ppm, DMSOd6, δ = 39.5 ppm). Splitting patterns are designated as s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; dd, double doublet. Coupling constants (J) are given in Hertz. The structures of the synthesized compounds were elucidated with the aid of 1D (1H, 1

1

1

13

C, APT, Gated 1H-

13

Decoupling) and 2D ( H- H COSY, H- C HMBC) NMR spectroscopy. High resolution mass spectra (HRMS) were obtained using Thermo ScientificTM LTQ Orbitrap and AB Sciex TripleTOF 5600+ mass spectrometers with a TurboV ESI source. Single crystal X-ray analysis was performed with Bruker SMART APEX II diffractometer. Crystallographic data were collected at 150 K using graphite monochromatized Mo Kα radiation (λ = 0.71073 A) using a ωscan mode. Absorption corrections based on measurements of equivalent reflections were applied (APEX II). The structures were solved by direct methods and refined by full matrix least-squares on F2 with anisotropic thermal parameters for all non-hydrogen atoms. Melting ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 8 of 42

points (mp) were determined using Electrothermal IA 9100 capillary melting point apparatus. Microwave reactions were performed in a Monowave 300 – Anton Paar microwave reactor in sealed reaction vessels. The temperature was monitored with installed IR detector. Analytical thin layer chromatography (TLC) was carried out with silica gel plates (silica gel 60, F254, supported on aluminium) visualized with UV lamp (254 nm). Column chromatography was performed on silica gel 60 (230-400 mesh). General procedure for the synthesis of alkenes S1. NaOH (158 mg, 3.95 mmol) was dissolved in a mixture of EtOH (7.9 mL) and water (7.9 mL). The corresponding 1-(4-methoxybenzyl)-1Hindole-2,3-dione or 1-methyl-1H-indole-2,3-dione (1.98 mmol) and aldehyde (2.18 mmol) were then added successively to the mixture under vigorous stirring. To ensure solubility of product under reaction conditions, CH2Cl2 (ca. 20% of initial solvent volume, 3 mL) was added. The reaction mixture was stirred vigorously at room temperature for the time specified. Then reaction mixture was poured into water (30 mL) and extracted with ethyl acetate (3×30 mL). Combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by column chromatography on silica gel (petroleum ether – ethyl acetate). Spectral data for alkenes S1a,22 S1j,23 S1q-u9a are consistent with those reported previously. 1-(4-Methoxybenzyl)-3-(4-methylbenzylidene)-1,3-dihydro-2H-indol-2-one

(S1b)

was

obtained from 4-methylbenzaldehyde (209 mg, 0.205 mL, 1.74 mmol) and 1-(4-methoxybenzyl)1,3-dihydro-2H-indol-2-one (400 mg, 1.58 mmol). Reaction time 2 h. Yield 362 mg (64%); yellow solid, mp 172–173 °C; E:Z = 84:16; Rf = 0.50 (E), 0.60 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1b: 1H NMR (600 MHz, CDCl3) δ = 2.44 (s, 3H, CH3), 3.78 (s, 3H, CH3O), 4.95 (s, 2H, CH2), 6.76 (d, 3J = 7.9 Hz, 1H, Ar), 6.85–6.88 (m, 3H, Ar), 7.16 (t, 3J = 7.7 Hz, 1H, Ar), 7.29–7.31 (m, 4H, Ar), 7.60 (d, 3J = 7.8 Hz, 2H, Ar), 7.72 (d, 3J = 7.6 Hz, 1H, Ar), 7.92 (s, 1H, CH=). 13C NMR (150 MHz, CDCl3) δ = 21.5 (CH3), 43.2 (CH2), 55.2 (CH3O), 109.1 (CH), 114.1 (2×CH), 121.4 (C), 121.7 (CH), 122.7 (CH), 126.3 (C), 128.1 (C), 128.7 (2×CH), 129.3 (3×CH), 129.4 (2×CH), 132.0 (C), 137.8 (CH=), 140.0 (C), 143.2 (C), 159.0 (C), 168.6 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H22NO2+ 356.1641; Found 356.1645. 1-(4-Methoxybenzyl)-3-(4-methoxybenzylidene)-1,3-dihydro-2H-indol-2-one

(S1c)

was

obtained from 4-methoxybenzaldehyde (118 mg, 0.106 mL, 0.87 mmol) and 1-(4methoxybenzyl)-1,3-dihydro-2H-indol-2-one (200 mg, 0.79 mmol). Reaction time 2.5 h. Yield 181 mg (62%); yellow solid, mp 166–167 °C; E:Z = 85:15; Rf = 0.36 (E), 0.46 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1c: 1H NMR (600 MHz, CDCl3) δ = 3.78 (s, 3H, CH3O), 3.90 (s, ACS Paragon Plus Environment

Page 9 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

3H, CH3O), 4.95 (s, 2H, CH2), 6.77 (d, 3J = 7.6 Hz, 1H, Ar), 6.86 (d, 3J = 8.7 Hz, 2H, Ar), 6.88 (t, 3J = 7.6 Hz, 1H, Ar), 7.01 (d, 3J = 8.7 Hz, 2H, Ar), 7.16 (t, 3J = 7.6 Hz, 1H, Ar), 7.29 (d, 3J = 8.7 Hz, 2H, Ar), 7.68 (d, 3J = 8.7 Hz, 2H, Ar), 7.76 (d, 3J = 7.6 Hz, 1H, Ar), 7.88 (s, 1H, CH=). 13

C NMR (150 MHz, CDCl3) δ = 43.2 (CH2), 55.2 (CH3O), 55.4 (CH3O), 109.1 (CH), 114.07

(2×CH), 114.09 (2×CH), 121.58 (C), 121.64 (CH), 122.4 (CH), 125.2 (C), 127.3 (C), 128.2 (C), 128.7 (2×CH), 129.2 (CH), 131.4 (2×CH), 137.7 (CH=), 143.1 (C), 159.0 (C), 160.8 (C), 168.8 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H22NO3+ 372.1605; Found 372.1594. 3-(4-Bromobenzylidene)-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one

was

(S1d)

obtained from 4-bromobenzaldehyde (322 mg, 1.74 mmol) and 1-(4-methoxybenzyl)-1,3dihydro-2H-indol-2-one (400 mg, 1.58 mmol). Reaction time 3 h. Yield 285 mg (43%); yellow solid, mp 166–167 °C; E:Z = 86:14; Rf = 0.54 (E), 0.66 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1d: 1H NMR (600 MHz, CDCl3) δ = 3.78 (s, 3H, CH3O), 4.94 (s, 2H, CH2), 6.77 (d, 3J = 7.6 Hz, 1H, Ar), 6.85–6.87 (m, 3H, Ar), 7.18 (td, 3J = 7.6, 4J = 1.1 Hz, 1H, Ar), 7.28–7.30 (m, 2H, Ar), 7.52–7.54 (m, 2H, Ar), 7.58 (d, 3J = 7.6 Hz, 1H, Ar), 7.60–7.62 (m, 2H, Ar), 7.81 (s, 1H, CH=).

13

C NMR (150 MHz, CDCl3) δ = 43.2 (CH2), 55.2 (CH3O), 109.3 (CH), 114.1 (2×CH),

120.9 (C), 121.8 (CH), 122.7 (CH), 123.7 (C), 127.6 (C), 127.9 (C), 128.7 (2×CH), 130.0 (CH), 130.8 (2×CH), 131.9 (2×CH), 133.8 (C), 135.7 (CH=), 143.4 (C), 159.0 (C), 168.2 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C23H19BrNO2+ 420.0594; Found 420.0601. 4-{[1-(4-Methoxybenzyl)-2-oxo-1,2-dihydro-3H-indol-3-ylidene]methyl}benzonitrile

(S1e)

was obtained from 4-cyanobenzaldehyde (285 mg, 2.174 mmol) and 1-(4-methoxybenzyl)-1,3dihydro-2H-indol-2-one (500 mg, 1.976 mmol). Reaction time 2 h. Yield 343 mg (47%); orange solid, mp 171–172 °C; E:Z = 80:20; Rf = 0.39 (E), 0.48 (petroleum ether – ethyl acetate, 3:1). ES1e: 1H NMR (600 MHz, CDCl3) δ = 3.77 (s, 3H, CH3O), 4.92 (s, 2H, CH2), 6.78 (d, 3J = 7.8 Hz, 1H, Ar), 6.84–6.87 (m, 3H, Ar), 7.20 (t, 3J = 7.8 Hz, 1H, Ar), 7.29 (d, 3J = 8.5 Hz, 2H, Ar), 7.43 (d, 3J = 7.6, 1H, Ar), 7.73 (d, 3J = 8.3 Hz, 2H, Ar), 7.76 (d, 3J = 8.3 Hz, 2H, Ar), 7.82 (s, 1H, CH=). 13C NMR (150 MHz, CDCl3) δ = 43.2 (CH2), 55.2 (CH3O), 109.5 (CH), 112.7 (C), 114.1 (2×CH), 118.3 (C), 120.4 (C), 121.9 (CH), 122.8 (CH), 127.7 (C), 128.6 (2×CH), 129.3 (C), 129.6 (2×CH), 130.6 (CH), 132.3 (2×CH), 134.0 (CH=), 139.7 (C), 143.8 (C), 159.0 (C), 167.8 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H19N2O2+ 367.1441; Found 367.1452. 1-(4-Methoxybenzyl)-3-(4-nitrobenzylidene)-1,3-dihydro-2H-indol-2-one (S1f) was obtained from 4-nitrobenzaldehyde (3.28 g, 21.7 mmol) and 1-(4-methoxybenzyl)-1,3-dihydro-2H-indol2-one (5 g, 19.8 mmol). Reaction time 2 h. Yield 4.30 g (56%); orange solid, mp 165–166 °C; E:Z = 73:27; Rf = 0.29 (E) (petroleum ether – ethyl acetate, 3:1). E-S1f: 1H NMR (600 MHz, ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 10 of 42

CDCl3) δ = 3.78 (s, 3H, CH3O), 4.94 (s, 2H, CH2), 6.79 (d, 3J = 7.9 Hz, 1H, Ar), 6.84–6.88 (m, 3H, Ar), 7.20–7.23 (m, 1H, Ar), 7.28–7.30 (m, 2H, Ar), 7.43–7.45 (m, 1H, Ar), 7.79–7.82 (m, 1H, Ar), 7.86 (s, 1H, CH=), 8.32–8.34 (m, 2H, Ar).

13

C NMR (150 MHz, CDCl3) δ = 43.3

(CH2), 55.2 (CH3O), 109.6 (CH), 114.2 (2×CH), 120.4 (C), 122.0 (CH), 122.9 (CH), 124.0 (2×CH), 127.7 (C), 128.7 (2×CH), 129.8 (C), 129.9 (2×CH), 130.8 (CH), 133.5 (CH=), 141.7 (C), 144.0 (C), 147.9 (C), 159.1 (C), 167.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C23H19N2O4+ 387.1339; Found 387.1342. 3-(Biphenyl-4-ylmethylidene)-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one (S1g) was obtained from 4-phenylbenzaldehyde (396 mg, 2.174 mmol) and 1-(4-methoxybenzyl)-1,3dihydro-2H-indol-2-one (500 mg, 1.976 mmol). Reaction time 2.5 h. Yield 460 mg (56%); yellow solid, mp 123–124 °C; E:Z = 81:19; Rf = 0.53 (E), 0.63 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1g: 1H NMR (600 MHz, CDCl3) δ = 3.78 (s, 3H, CH3O), 4.98 (s, 2H, CH2), 6.82 (d, 3J = 7.8 Hz, 1H, Ar), 6.90–6.93 (m, 3H, Ar), 7.21 (td, 3J = 7.7, 4J = 1.0 Hz, 1H, Ar), 7.35–7.37 (m, 2H, Ar), 7.43 (tt, 3J = 7.4, 4J = 1.1 Hz, 1H, Ar), 7.49–7.52 (m, 2H, Ar), 7.70–7.72 (m, 2H, Ar), 7.73–7.75 (m, 2H, Ar), 7.79–7.80 (m, 2H, Ar), 7.82 (d, 3J = 7.6, 1H, Ar), 8.02 (s, 1H, CH=).

13

C NMR (150 MHz, CDCl3) δ = 43.0 (CH2), 55.0 (CH3O), 109.0 (CH), 113.9

(2×CH), 121.1 (C), 121.6 (CH), 123.0 (CH), 126.7 (C), 126.8 (2×CH), 127.0 (2×CH), 127.7 (CH), 127.9 (C), 128.5 (2×CH), 128.7 (2×CH), 129.5 (CH), 129.8 (2×CH), 133.6 (C), 136.8 (CH=), 139.8 (C), 142.1 (C), 143.2 (C), 158.8 (C), 168.3 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C29H24NO2+ 418.1802; Found 418.1804. 1-(4-Methoxybenzyl)-3-(naphth-1-ylmethylidene)-1,3-dihydro-2H-indol-2-one

(S1h)

was

obtained from 1-naphthaldehyde (339 mg, 0.295 mL, 2.174 mmol) and 1-(4-methoxybenzyl)1,3-dihydro-2H-indol-2-one (500 mg, 1.976 mmol). Reaction time 2 h. Yield 598 mg (77%); yellow solid, mp 166–167 °C; E:Z = 97:3; Rf = 0.49 (E), 0.58 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1h: 1H NMR (600 MHz, CDCl3) δ = 3.80 (s, 3H, CH3O), 5.00 (s, 2H, CH2), 6.72 (td, 3J = 7.7, 4J = 1.0 Hz, 1H, Ar), 6.78 (br.d, 3J = 7.8 Hz, 1H, Ar), 6.89–6.91 (m, 2H, Ar), 7.13 (td, 3J = 7.7, 4J = 1.1 Hz, 1H, Ar), 7.17–7.19 (m, 1H, Ar), 7.35–7.37 (m, 2H, Ar), 7.54–7.59 (m, 3H, Ar), 7.85 (dt, 3J = 7.1, 4J = 1.0 Hz, 1H, Ar), 7.94–7.98 (m, 2H, Ar), 8.06–8.08 (m, 1H, Ar), 8.44 (s, 1H, CH=). 13C NMR (150 MHz, CDCl3) δ = 43.2 (CH2), 55.2 (CH3O), 109.1 (CH), 114.1 (2×CH), 121.3 (C), 121.7 (CH), 123.1 (CH), 124.8 (CH), 125.1 (CH), 126.5 (CH), 126.7 (CH), 126.8 (CH), 128.1 (C), 128.6 (CH), 128.75 (2×CH), 128.79 (C), 129.6 (CH), 129.9 (CH), 131.3 (C), 132.2 (C), 133.6 (C), 135.4 (CH=), 143.4 (C), 159.0 (C), 168.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C27H22NO2+ 392.1645; Found 392.1650.

ACS Paragon Plus Environment

Page 11 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

3-(1,3-Benzodioxol-5-ylmethylidene)-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one (S1i) was obtained from 3,4-(methylenedioxy)benzaldehyde (261 mg, 1.739 mmol) and 1-(4methoxybenzyl)-1,3-dihydro-2H-indol-2-one (400 mg, 1.581 mmol). Reaction time 3 h. Yield 215 mg (35%); yellow solid, mp 159–160 °C; E:Z = 78:22; Rf = 0.47 (E), 0.56 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1i: 1H NMR (600 MHz, CDCl3) δ = 3.78 (s, 3H, CH3O), 4.94 (s, 2H, CH2), 6.06 (s, 2H, OCH2O), 6.76 (d, 3J = 7.6 Hz, 1H, Ar), 6.85–6.96 (m, 2H, Ar), 6.88–6.92 (m, 2H, Ar), 7.15–7.19 (m, 2H, Ar), 7.22–7.24 (m, 1H, Ar), 7.27–7.29 (m, 2H, Ar), 7.76–7.77 (m, 1H, Ar), 7.82 (s, 1H, CH=).

13

C NMR (150 MHz, CDCl3) δ = 43.2 (CH2), 55.2 (CH3O),

101.5 (OCH2O), 108.6 (CH), 109.1 (CH), 109.4 (CH), 114.1 (2×CH), 121.3 (C), 121.7 (CH), 122.6 (CH), 124.7 (CH), 125.7 (C), 128.1 (C), 128.7 (2×CH), 128.8 (C), 129.4 (CH), 137.5 (CH=), 143.2 (C), 147.9 (C), 148.9 (C), 159.0 (C), 168.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H20NO4+ 386.1387; Found 386.1392. 1-(4-Methoxybenzyl)-3-(thien-2-ylmethylidene)-1,3-dihydro-2H-indol-2-one

(S1k)

was

obtained from 2-thiophenecarboxaldehyde (244 mg, 0.205 mL, 2.174 mmol) and 1-(4methoxybenzyl)-1,3-dihydro-2H-indol-2-one (500 mg, 1.976 mmol). Reaction time 2.5 h. Yield 569 mg (83%); brown oil; E:Z = 63:37; Rf = 0.48 (E), 0.59 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1k: 1H NMR (600 MHz, CDCl3) δ = 3.69 (s, 3H, CH3O), 4.90 (s, 2H, CH2), 6.76 (d, 3J = 7.8 Hz, 1H, Ar), 6.82–6.84 (m, 2H, Ar), 6.98–7.01 (m, 1H, Ar), 7.10–7.11 (m, 1H, Ar), 7.15– 7.17 (m, 1H, Ar), 7.27–7.28 (m, 2H, Ar), 7.51–7.52 (m, 1H, Ar), 7.54–7.55 (m, 1H, Ar), 8.02 (s, 1H, CH=), 8.22 (d, 3J = 7.7 Hz, 1H, Ar).

13

C NMR (150 MHz, CDCl3) δ = 42.8 (CH2), 54.7

(CH3O), 108.7 (CH), 113.7 (2×CH), 120.7 (C), 121.5 (CH), 122.9 (C), 123.1 (CH), 127.7 (CH), 127.8 (C), 128.1 (CH), 128.3 (2×CH), 129.0 (CH), 130.3 (CH), 134.3 (CH=), 137.4 (C), 142.6 (C), 158.6 (C), 168.6 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C21H18NO2S+ 348.1053; Found 348.1050. 3-Benzylidene-5-methyl-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one

(S1l)

was

obtained from benzaldehyde (3.5 g, 3.4 mL, 33 mmol) and 5-methyl-1-(4-methoxybenzyl)-1,3dihydro-2H-indol-2-one (8.01 g, 30 mmol). Reaction time 2.5 h. Yield 5.19 g (58%); yellow foam; E:Z = 85:15; Rf = 0.43 (E), 0.51 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1l: 1H NMR (600 MHz, CDCl3) δ = 2.20 (CH3), 3.73 (s, 3H, CH3O), 4.92 (s, 2H, CH2), 6.67 (br.d, 3J = 7.8 Hz, 1H, Ar), 6.86–6.88 (m, 2H, Ar), 6.96–6.98 (m, 1H, Ar), 7.31–7.33 (m, 2H, Ar), 7.43–7.45 (m, 1H, Ar), 7.46–7.49 (m, 2H, Ar), 7.51–7.52 (m, 1H, Ar), 7.68–7.70 (m, 2H, Ar), 7.96 (br.s, 1H, CH=).

13

C NMR (150 MHz, CDCl3) δ = 20.78 (CH3), 42.8 (CH2), 54.75 (CH3O), 108.6

(CH), 113.8 (2×CH), 120.9 (C), 123.1 (CH), 127.0 (C), 127.91 (CH), 127.93 (C), 128.3 (2×CH), 128.37 (2×CH), 129.0 (2×CH), 129.8 (CH), 130.7 (C), 134.7 (C), 136.6 (CH=), 140.9 (C), 158.7 ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 42

(C), 168.1 (CO). Z-S1l: 1H NMR (600 MHz, CDCl3) δ = 2.36 (CH3), 3.72 (s, 3H, CH3O), 4.90 (s, 2H, CH2), 6.65 (br.d, 3J = 7.6 Hz, 1H, Ar), 6.84–6.87 (m, 2H, Ar), 6.98–7.00 (m, 1H, Ar), 7.30–7.32 (m, 2H, Ar), 7.35–7.36 (m, 1H, Ar), 7.42–7.44 (m, 3H, Ar), 7.46–7.49 (m, 2H, Ar), 7.54 (br.s, 1H, CH=), 8.40–8.42 (m, 2H, Ar).

13

C NMR (150 MHz, CDCl3) δ = 20.81 (CH3),

42.6 (CH2), 54.74 (CH3O), 108.2 (CH), 113.7 (2×CH), 119.4 (CH), 124.1 (C), 125.8 (C), 128.1 (C), 128.41 (2×CH), 128.9 (CH), 129.2 (2×CH), 130.1 (CH), 130.8 (C), 131.8 (2×CH), 133.6 (C), 136.5 (CH=), 139.0 (C), 158.6 (C), 165.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H22NO2+ 356.1645; Found 356.1651. 3-Benzylidene-5-fluoro-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one

(S1m)

was

obtained from benzaldehyde (2.16 g, 2.1 mL, 20.4 mmol) and 5-fluoro-1-(4-methoxybenzyl)1,3-dihydro-2H-indol-2-one (5 g, 18.5 mmol). Reaction time 2.5 h. Yield 3.45 g (52%); yellow foam; E:Z = 90:10; Rf = 0.45 (E), 0.58 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1m: 1H NMR (600 MHz, CDCl3) δ = 3.79 (s, 3H, CH3O), 4.93 (s, 2H, CH2), 6.66 (dd, 3J = 8.5, 4J = 4.3 Hz, 1H, Ar), 6.85–6.89 (m, 3H, Ar), 7.27–7.29 (m, 2H, Ar), 7.35 (dd, 3J = 9.0, 4J = 2.5 Hz, 1H, Ar), 7.45–7.52 (m, 3H, Ar), 7.63–7.65 (m, 2H, Ar), 7.99 (s, 1H, CH=).

13

C NMR (150 MHz,

CDCl3) δ = 43.3 (CH2), 55.2 (CH3O), 109.5 (3JCF = 8 Hz, CH), 110.4 (2JCF = 26 Hz, CH), 114.2 (2×CH), 115.8 (2JCF = 24 Hz, CH), 122.3 (3JCF = 9 Hz, C), 126.8 (4JCF = 3 Hz, C), 127.8 (C), 128.7 (2×CH), 128.8 (2×CH), 129.1 (2×CH), 129.9 (CH), 134.5 (C), 138.9 (CH=), 139.4 (C), 158.4 (1JCF = 239 Hz, C), 159.1 (C), 168.3 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C23H19FNO2+ 360.1394; Found 360.1401. Ethyl

4-{[5-fluoro-1-(4-methoxybenzyl)-2-oxo-1,2-dihydro-3H-indol-3-

ylidene]methyl}benzoate (S1n) was obtained from methyl 4-formylbenzoate (3.54 g, 21.6 mmol) and 5-fluoro-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one (5.32 g, 19.6 mmol). Reaction time 2 h. Transesterification of the methyl ester into the ethyl one occurred under the reaction conditions. Yield 3.13 g (37%); orange solid, mp 145–146 °C; E:Z = 81:19; Rf = 0.25 (E), 0.35 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1n: 1H NMR (600 MHz, CDCl3) δ = 1.44 (t, 3J = 7.2 Hz, 3H, CH3), 3.79 (s, 3H, CH3O), 4.44 (q, 3J = 7.2 Hz, 2H, CH2O), 4.92 (s, 2H, CH2), 6.66 (dd, 3J = 8.5, 4J = 4.3 Hz, 1H, Ar), 6.85–6.90 (m, 3H, Ar), 7.24 (dd, 3J = 8.9, 4J = 2.6 Hz, 1H, Ar), 7.25–7.28 (m, 3H, Ar), 7.68–7.70 (m, 2H, Ar), 7.96 (s, 1H, CH=), 8.16–8.18 (m, 2H, Ar). 13C NMR (150 MHz, CDCl3) δ = 14.3 (CH3), 43.4 (CH2), 55.2 (CH3O), 61.3 (CH2O), 109.8 (3JCF = 8 Hz, CH), 110.6 (2JCF = 26 Hz, CH), 114.2 (2×CH), 116.4 (2JCF = 24 Hz, CH), 121.8 (3JCF = 9 Hz, C), 127.6 (C), 128.2 (4JCF = 3 Hz, C), 128.7 (2×CH), 129.0 (2×CH), 130.0 (2×CH), 131.4 (C), 137.2 (CH=), 138.9 (C), 139.7 (C), 158.4 (1JCF = 239 Hz, C), 159.1 (C),

ACS Paragon Plus Environment

Page 13 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

165.9 (CO), 167.9 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C26H23FNO4+ 432.1606; Found 432.1613. 3-Benzylidene-5-chloro-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one

(S1o)

was

obtained from benzaldehyde (2.16 g, 2.1 mL, 20.4 mmol) and 5-chloro-1-(4-methoxybenzyl)1,3-dihydro-2H-indol-2-one (5.33 g, 18.5 mmol). Reaction time 2.5 h. Yield 4.25 g (61%); yellow foam; E:Z = 88:12; Rf = 0.44 (E), 0.56 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1o: 1

H NMR (600 MHz, CDCl3) δ = 3.78 (s, 3H, CH3O), 4.93 (s, 2H, CH2), 6.67 (d, 3J = 8.4 Hz, 1H,

Ar), 6.86–6.88 (m, 2H, Ar), 7.13 (dd, 3J = 8.4, 4J = 2.1 Hz, 1H, Ar), 7.26–7.27 (m, 2H, Ar), 7.46–7.52 (m, 3H, Ar), 7.60 (br.d, 2J = 2.1 Hz, 1H, Ar), 7.64–7.66 (m, 2H, Ar), 7.98 (s, 1H, CH=).

13

C NMR (150 MHz, CDCl3) δ = 43.3 (CH2), 55.2 (CH3O), 110.0 (CH), 114.2 (2×CH),

122.6 (C), 122.8 (CH), 126.2 (C), 127.1 (C), 127.6 (C), 128.6 (2×CH), 128.8 (2×CH), 129.2 (2×CH), 129.3 (CH), 130.0 (CH), 134.4 (C), 139.1 (CH=), 141.8 (C), 159.1 (C), 168.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C23H19ClNO2+ 376.1099; Found 376.1105. 3-Benzylidene-5-bromo-1-(4-methoxybenzyl)-1,3-dihydro-2H-indol-2-one

(S1p)

was

obtained from benzaldehyde (2.16 g, 2.1 mL, 20.4 mmol) and 5-bromo-1-(4-methoxybenzyl)1,3-dihydro-2H-indol-2-one (6.14 g, 18.5 mmol). Reaction time 2.5 h. Yield 3.77 g (49%); yellow foam; E:Z = 95:5; Rf = 0.35 (E), 0.44 (Z) (petroleum ether – ethyl acetate, 3:1). E-S1p: 1H NMR (600 MHz, CDCl3) δ = 3.79 (s, 3H, CH3O), 4.93 (s, 2H, CH2), 6.63 (d, 3J = 8.4 Hz, 1H, Ar), 6.86–6.87 (m, 2H, Ar), 7.25–7.27 (m, 3H, Ar), 7.48–7.53 (m, 3H, Ar), 7.64–7.66 (m, 2H, Ar), 7.75 (br.d, 2J = 1.9 Hz, 1H, Ar), 7.97 (s, 1H, CH=). 13C NMR (150 MHz, CDCl3) δ = 43.3 (CH2), 55.3 (CH3O), 110.5 (CH), 114.2 (2×CH), 114.5 (C), 123.1 (C), 125.6 (CH), 126.1 (C), 127.6 (C), 128.7 (2×CH), 128.8 (2×CH), 129.2 (2×CH), 130.1 (CH), 132.1 (CH), 134.4 (C), 139.2 (CH=), 142.2 (C), 159.1 (C), 168.0 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C23H19BrNO2+ 420.0594; Found 420.0599. General procedure for the synthesis of cyclopropanes 1. Trimethylsulfoxonium iodide (660 mg, 3.00 mmol, 2.0 equiv) was added to a suspension of NaH (120 mg, 3.00 mmol, 2.0 equiv) in anhydrous DMF (2.5 mL) under an argon atmosphere. The resulting suspension was stirred for 20 min, then a solution of alkene S1 (1.50 mmol, 1.0 equiv) in DMF (15 mL) was added in one portion. The reaction mixture was stirred at room temperature for the time specified. The resulting mixture was poured into 30 mL of ice water and extracted with EtOAc (3×30 mL). Combined organic layers were washed with brine (5×15 mL), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by column chromatography on

ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 42

silica gel (petroleum ether – ethyl acetate). Spectral data for cyclopropanes 1q-u9a are consistent with those reported previously. 1'-(4-Methoxybenzyl)-2-phenylspiro[cyclopropane-1,3'-indol]-2'(1'H)-one (1a) was obtained from S1a (550 mg, 1.61 mmol). Reaction time 2 h. Yield 500 mg (87%); yellowish foam; dr 70:30; Rf = 0.83 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.05 (dd, 2

J = 4.5, 3J = 7.9 Hz, 1H, CH2, A), 2.13 (dd, 2J = 4.9, 3J = 9.1 Hz, 1H, CH2, B), 2.28 (dd, 2J =

4.5, 3J = 9.4 Hz, 1H, CH2, A), 2.49 (dd, 2J = 4.9, 3J = 8.7 Hz, 1H, CH2, B), 3.20 (dd, 3J = 9.1 3J = 8.7 Hz, 1H, CH, B), 3.42 (dd, 3J = 9.4, 3J = 7.9 Hz, 1H, CH, A), 3.77 (s, 3H, CH3O, B), 3.80 (s, 3H, CH3O, A), 4.81 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.84 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.95 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.02 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.97 (dd, 3J = 7.6, 4J = 0.8 Hz, 1H, Ar, A), 6.65–6.68 (m, 1H, Ar, A), 6.80–6.84 (m, 2H+1H, Ar, A, B), 6.88–6.90 (m, 2H, Ar, A), 6.98–6.99 (m, 1H, Ar, B), 7.04–7.07 (m, 1H+1H, Ar, A, B), 7.18–7.22 (m, 3H+1H, Ar, A, B), 7.26–7.37 (m, 3H+9H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 22.6 (CH2), 33.2 (C), 36.0 (CH), 43.6 (CH2), 55.22 (CH3O), 108.72 (CH), 114.1 (2×CH), 120.7 (CH), 121.4 (CH), 126.4 (CH), 127.4 (CH), 127.5 (C), 128.32 (C), 128.34 (2×CH), 128.7 (2×CH), 129.9 (2×CH), 135.1 (C), 142.9 (C), 159.0 (C), 176.5 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 22.3 (CH2), 33.8 (C), 38.4 (CH), 43.3 (CH2), 55.18 (CH3O), 108.73 (CH), 114.0 (2×CH), 118.1 (CH), 121.8 (CH), 126.6 (CH), 127.2 (CH), 127.9 (2×CH), 128.5 (C), 128.8 (2×CH), 129.3 (2×CH), 130.8 (C), 134.4 (C), 142.5 (C), 158.9 (C), 173.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H22NO2+ 356.1645; Found 356.1630. 1'-(4-Methoxybenzyl)-2-(p-tolyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1b)

was

obtained from S1b (310 mg, 0.873 mmol). Reaction time 2 h. Yield 250 mg (76%); yellow oil; dr 72:28; Rf = 0.58 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 2.12 (dd, 2J = 4.4, 3J = 7.9 Hz, 1H, CH2, A), 2.17 (dd, 2J = 4.9, 3J = 9.0 Hz, 1H, CH2, B), 2.36 (dd, 2J = 4.4, 3J = 9.2 Hz, 1H, CH2, A), 2.42 (s, 3H, CH3), 2.44 (s, 3H, CH3), 2.56 (dd, 2J = 4.9, 3J = 8.6 Hz, 1H, CH2, B), 3.25 (dd, 3J = 9.0 3J = 8.6 Hz, 1H, CH, B), 3.50 (dd, 3J = 9.2, 3J = 7.9 Hz, 1H, CH, A), 3.81 (s, 3H, CH3O, B), 3.83 (s, 3H, CH3O, A), 4.92 (d, 2J = 15.7 Hz, 1H, CH2, B), 4.95 (d, 2J = 15.7 Hz, 1H, CH2, B), 5.04 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.11 (d, 2J = 15.4 Hz, 1H, CH2, A), 6.15 (br.d, 3J = 7.5 Hz, 1H, Ar, A), 6.75–6.78 (m, 1H, Ar, A), 6.90–6.93 (m, 2H+1H, Ar, A, B), 6.97–6.98 (m, 2H, Ar, A), 7.03–7.04 (m, 1H, Ar, B), 7.11–7.15 (m, 1H+1H, Ar, A, B), 7.19–7.20 (m, 2H+5H, Ar, A, B), 7.24–7.26 (m, 1H, Ar, A), 7.28–7.29 (m, 2H, Ar, B), 7.34– 7.36 (m, 2H, Ar, B), 7.40–7.41 (m, 2H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 20.9 (1JCH = 125 Hz, CH3), 22.4 (1JCH = 165 Hz, CH2), 33.0 (C), 35.7 (1JCH = 165 Hz, CH), 43.3 (1JCH = 139

ACS Paragon Plus Environment

Page 15 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Hz, CH2), 54.90 (1JCH = 144 Hz, CH3O), 108.47 (CH), 113.9 (2×CH), 120.5 (CH), 121.2 (CH), 126.2 (CH), 127.4 (C), 128.1 (C), 128.4 (2×CH), 128.8 (2×CH), 129.5 (2×CH), 131.7 (C), 136.7 (C), 142.7 (C), 158.8 (C), 176.3 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 21.0 (1JCH = 125 Hz, CH3), 22.1 (1JCH = 165 Hz, CH2), 33.6 (C), 38.1 (1JCH = 162 Hz, CH), 43.0 (1JCH = 139 Hz, CH2), 54.87 (1JCH = 144 Hz, CH3O), 108.49 (CH), 113.7 (2×CH), 117.9 (CH), 121.6 (CH), 126.3 (CH), 128.3 (C), 128.4 (2×CH), 128.5 (2×CH), 128.9 (2×CH), 130.6 (C), 131.1 (C), 136.5 (C), 142.2 (C), 158.7 (C), 173.5 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H24NO2+ 370.1802; Found 370.1795. 1'-(4-Methoxybenzyl)-2-(4-methoxyphenyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one (1c) was obtained from S1c (1.02 g, 3.85 mmol). Reaction time 2.5 h. Yield 0.90 g (84%); yellow viscous oil; dr 68:32; Rf = 0.59 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.04 (dd, 2J = 4.4, 3J = 8.0 Hz, 1H, CH2, A), 2.12 (dd, 2J = 4.9, 3J = 9.0 Hz, 1H, CH2, B), 2.31 (dd, 2J = 4.4, 3J = 9.2 Hz, 1H, CH2, A), 2.49 (dd, 2J = 4.9, 3J = 8.5 Hz, 1H, CH2, B), 3.18 (dd, 3J = 9.0 3J = 8.5 Hz, 1H, CH, B), 3.42 (dd, 3J = 9.2, 3J = 8.0 Hz, 1H, CH, A), 3.75 (s, 3H, CH3O, B), 3.78 (s, 3H, CH3O, A), 3.79 (s, 3H, CH3O, A), 3.81 (s, 3H, CH3O, B), 4.84 (d, 2J = 15.4 Hz, 1H, CH2, B), 4.88 (d, 2J = 15.4 Hz, 1H, CH2, B), 4.99 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.05 (d, 2J = 15.4 Hz, 1H, CH2, A), 6.08 (br.d, 3J = 7.4 Hz, 1H, Ar, A), 6.70–6.73 (m, 1H, Ar, A), 6.84–6.90 (m, 3H+3H, Ar, A, B), 6.91–6.94 (m, 2H+2H, Ar, A, B), 6.98–6.99 (m, 1H, Ar, B), 7.05–7.08 (m, 1H, Ar, B), 7.07–7.10 (m, 1H, Ar, A), 7.16–7.17 (m, 2H, Ar, A), 7.19–7.22 (m, 1H, Ar, B), 7.22–7.24 (m, 2H, Ar, B), 7.31–7.33 (m, 2H, Ar, B), 7.35–7.36 (m, 2H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 22.6 (CH2), 33.1 (C), 35.4 (CH), 43.3 (CH2), 54.85 (CH3O), 54.88 (CH3O), 108.4 (CH), 113.5 (2×CH), 113.9 (2×CH), 120.5 (CH), 121.2 (CH), 126.1 (CH), 126.8 (C), 127.3 (C), 128.2 (C), 128.4 (2×CH), 130.7 (2×CH), 142.7 (C), 158.6 (C), 158.8 (C), 176.2 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 22.1 (CH2), 33.6 (C), 38.0 (CH), 42.9 (CH2), 54.8 (CH3O), 54.85 (CH3O), 108.4 (CH), 113.1 (2×CH), 113.7 (2×CH), 117.8 (CH), 121.6 (CH), 126.3 (CH), 128.3 (C), 128.5 (2×CH), 128.6 (C), 130.1 (2×CH), 130.6 (C), 142.1 (C), 158.4 (C), 158.7 (C), 173.5 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H24NO3+ 386.1751; Found 386.1759. 2-(4-Bromophenyl)-1'-(4-methoxybenzyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1d)

was obtained from S1d (413 mg, 0.983 mmol). Reaction time 3 h. Yield 231 mg (54%); yellow solid, mp 123–124 °C; dr 60:40; Rf = 0.66 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.00 (dd, 2J = 4.6, 3J = 7.9 Hz, 1H, CH2, A), 2.13 (dd, 2J = 5.0, 3J = 9.0 Hz, 1H, CH2, B), 2.30 (dd, 2J = 4.6, 3J = 9.2 Hz, 1H, CH2, A), 2.45 (dd, 2J = 5.0, 3J = 8.5 Hz, 1H, ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

CH2, B), 3.13 (dd, 3J = 9.0, 3J = 8.5 Hz, 1H, CH, B), 3.35 (dd, 3J = 9.2, 3J = 7.9 Hz, 1H, CH, A), 3.76 (s, 3H, CH3O, B), 3.78 (s, 3H, CH3O, A), 4.82 (d, 2J = 15.4 Hz, 1H, CH2, B), 4.85 (d, 2J = 15.4 Hz, 1H, CH2, B), 4.96 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.04 (d, 2J = 15.5 Hz, 1H, CH2, A), 6.03 (br.d, 3J = 7.5 Hz, 1H, Ar, A), 6.72–6.74 (m, 1H, Ar, A), 6.84–6.89 (m, 2H+2H, Ar, A, B), 6.90–6.92 (m, 2H, Ar, A), 6.98–6.99 (m, 1H, Ar, B), 7.05–7.08 (m, 1H, Ar, B), 7.09–7.11 (m, 2H+2H, Ar, A, B), 7.20–7.22 (m, 2H, Ar, B), 7.23–7.25 (m, 2H, Ar, B), 7.33–7.34 (m, 2H, Ar, A), 7.44–7.45 (m, 2H, Ar, A), 7.46–7.48 (m, 2H, Ar, B). A: 13C NMR (150 MHz, CDCl3) δ = 22.2 (1JCH = 165 Hz, CH2), 32.9 (C), 35.0 (1JCH = 165 Hz, CH), 43.4 (1JCH = 139 Hz, CH2), 54.99 (1JCH = 144 Hz, CH3O), 108.71 (CH), 114.0 (2×CH), 120.5 (CH), 121.2 (C), 121.4 (CH), 126.5 (CH), 126.8 (C), 128.0 (C), 128.3 (C), 128.5 (2×CH), 131.3 (2×CH), 131.4 (2×CH), 134.0 (C), 142.7 (C), 158.8 (C), 176.0 (CO). B:

13

C NMR (150 MHz, CDCl3) δ = 22.0 (1JCH = 165 Hz,

CH2), 33.6 (C), 37.4 (1JCH = 165 Hz, CH), 43.1 (1JCH = 139 Hz, CH2), 54.97 (1JCH = 144 Hz, CH3O), 108.68 (CH), 113.8 (2×CH), 118.0 (CH), 121.0 (C), 121.8 (CH), 126.7 (CH), 128.1 (C), 128.6 (2×CH), 130.2 (C), 130.78 (2×CH), 130.80 (2×CH), 131.2 (C), 133.3 (C), 142.2 (C), 158.7 (C), 173.3 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H21BrNO2+ 434.0750; Found 434.0768. 4-[1'-(4-Methoxybenzyl)-2'-oxo-1',2'-dihydrospiro[cyclopropane-1,3'-indol]-2yl]benzonitrile (1e) was obtained from S1e (291 mg, 0.795 mmol). Reaction time 2 h. Yield 250 mg (83%); beige solid, mp 136–137 °C; dr 58:42; Rf = 0.31 (petroleum ether – ethyl acetate, 3:1). 1

H NMR (600 MHz, CDCl3) δ = 2.03 (dd, 2J = 4.7, 3J = 7.8 Hz, 1H, CH2, A), 2.15 (dd, 2J = 5.2,

3

J = 8.8 Hz, 1H, CH2, B), 2.30 (dd, 2J = 4.7, 3J = 9.1 Hz, 1H, CH2, A), 2.44 (dd, 2J = 5.2, 3J = 8.4

Hz, 1H, CH2, B), 3.17 (dd, 3J = 8.8, 3J = 8.4 Hz, 1H, CH, B), 3.38 (dd, 3J = 9.1, 3J = 7.8 Hz, 1H, CH, A), 3.70 (s, 3H, CH3O, B), 3.72 (s, 3H, CH3O, A), 4.76 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.80 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.93 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.00 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.96 (br.d, 3J = 7.5 Hz, 1H, Ar, A), 6.67–6.70 (m, 1H, Ar, A), 6.80–6.81 (m, 2H, Ar, B), 6.85–6.87 (m, 4H, Ar, A), 6.92–6.99 (m, 1H, Ar, B), 7.03–7.08 (m, 1H+1H, Ar, A, B), 7.16– 7.20 (m, 3H, Ar, B), 7.29–7.32 (m, 3H+1H, Ar, A, B), 7.42–7.43 (m, 2H, Ar, B), 7.54–7.57 (m, 2H+2H, Ar, A, B). A: 13C NMR (150 MHz, CDCl3) δ = 21.5 (1JCH = 165 Hz, CH2), 33.0 (C), 35.0 (1JCH = 166 Hz, CH), 43.2 (1JCH = 139 Hz, CH2), 54.75 (1JCH = 144 Hz, CH3O), 108.7 (CH), 110.7 (C), 113.8 (2×CH), 118.3 (C), 120.1 (CH), 121.2 (CH), 126.0 (C), 126.6 (CH), 127.7 (C), 128.32 (2×CH), 130.3 (2×CH), 131.7 (2×CH), 140.3 (C), 142.6 (C), 158.7 (C), 175.3 (CO). B: 13

C NMR (150 MHz, CDCl3) δ = 21.7 (1JCH = 165 Hz, CH2), 33.9 (C), 37.0 (1JCH = 163 Hz, CH),

42.9 (1JCH = 139 Hz, CH2), 54.73 (1JCH = 144 Hz, CH3O), 108.6 (CH), 110.3 (C), 113.6 (2×CH), 118.1 (CH), 118.6 (C), 121.8 (CH), 126.8 (CH), 127.8 (C), 128.33 (2×CH), 129.5 (C), 129.7 ACS Paragon Plus Environment

Page 16 of 42

Page 17 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

(2×CH), 131.1 (2×CH), 139.8 (C), 142.1 (C), 158.6 (C), 172.8 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H21N2O2+ 381.1598; Found 381.1598. 1'-(4-Methoxybenzyl)-2-(4-nitrophenyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one (1f) was obtained from S1f (830 mg, 2.2 mmol). Reaction time 2 h. Yield 675 mg (77%); yellow foam; dr 72:28; Rf = 0.33 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 2.07 (dd, 2

J = 4.8, 3J = 8.0 Hz, 1H, CH2, A), 2.22 (dd, 2J = 5.2, 3J = 8.9 Hz, 1H, CH2, B), 2.35 (dd, 2J =

4.8, 3J = 9.1 Hz, 1H, CH2, A), 2.50 (dd, 2J = 5.2, 3J = 8.5 Hz, 1H, CH2, B), 3.22 (dd, 3J = 8.9, 3J = 8.5 Hz, 1H, CH, B), 3.41 (dd, 3J = 9.1, 3J = 8.0 Hz, 1H, CH, A), 3.76 (s, 3H, CH3O, B), 3.79 (s, 3H, CH3O, A), 4.79 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.82 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.94 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.03 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.95 (br.d, 3J = 7.6 Hz, 1H, Ar, A), 6.68–6.70 (m, 1H, Ar, A), 6.81–6.83 (m, 2H, Ar, B), 6.85–6.87 (m, 1H+1H, Ar, A, B), 6.87–6.90 (m, 2H, Ar, A), 7.00–7.02 (m, 1H, Ar, B), 7.06–7.10 (m, 1H+1H, Ar, A, B), 7.15–7.18 (m, 2H, Ar, B), 7.20–7.23 (m, 1H, Ar, B), 7.28–7.32 (m, 2H, Ar, A), 7.37–7.39 (m, 2H, Ar, A), 7.50–7.52 (m, 2H, Ar, B), 8.16–8.19 (m, 2H+2H, Ar, A, B). A: 13C NMR (150 MHz, CDCl3) δ = 22.1 (CH2), 33.3 (C), 35.0 (CH), 43.6 (CH2), 55.13 (CH3O), 109.1 (CH), 114.1 (2×CH), 120.3 (CH), 121.6 (CH), 123.5 (2×CH), 126.2 (C), 127.0 (CH), 128.0 (C), 128.6 (2×CH), 130.7 (2×CH), 142.8 (C), 143.0 (C), 147.0 (C), 159.0 (C), 175.6 (CO). B:

13

C NMR (150 MHz,

CDCl3) δ = 22.2 (CH2), 34.3 (C), 37.0 (CH), 43.3 (CH2), 55.11 (CH3O), 109.0 (CH), 114.0 (2×CH), 118.3 (CH), 122.0 (CH), 122.1 (CH), 123.0 (2×CH), 128.0 (C), 128.7 (2×CH), 129.7 (C), 130.1 (2×CH), 142.2 (C), 142.5 (C), 146.8 (C), 158.9 (C), 173.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H21N2O4+ 401.1496; Found 401.1501. 2-([1,1'-Biphenyl]-4-yl)-1'-(4-methoxybenzyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one (1g) was obtained from S1g (395 mg, 0.947 mmol). Reaction time 2.5 h. Yield 320 mg (78%); light yellow solid, mp 158–160 °C; dr 65:35; Rf = 0.43 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 2.18 (dd, 2J = 4.5, 3J = 7.9 Hz, 1H, CH2, A), 2.22 (dd, 2J = 4.9, 3J = 9.0 Hz, 1H, CH2, B), 2.42 (dd, 2J = 4.5, 3J = 9.2 Hz, 1H, CH2, A), 2.63 (dd, 2J = 4.9, 3J = 8.6 Hz, 1H, CH2, B), 3.30 (dd, 3J = 9.0, 3J = 8.6 Hz, 1H, CH, B), 3.58 (dd, 3J = 9.2, 3J = 7.9 Hz, 1H, CH, A), 3.80 (s, 3H, CH3O, B), 3.84 (s, 3H, CH3O, A), 4.91 (d, 2J = 15.7 Hz, 1H, CH2, B), 4.94 (d, 2J = 15.7 Hz, 1H, CH2, B), 5.07 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.13 (d, 2J = 15.4 Hz, 1H, CH2, A), 6.22 (br.d, 3J = 7.6 Hz, 1H, Ar, A), 6.76–6.79 (m, 1H, Ar, A), 6.91–6.95 (m, 1H+3H, Ar, A, B), 6.98–7.01 (m, 2H, Ar, A), 7.06 (d, 3J = 7.4 Hz, 1H, Ar, B), 7.13–7.17 (m, 1H+1H, Ar, A, B), 7.28–7.31 (m, 1H+1H, Ar, A, B), 7.36–7.41 (m, 2H, Ar, A), 7.42–7.45 (m, 2H+3H, Ar, A, B), 7.51–7.55 (m, 2H+4H, Ar, A, B), 7.64–7.68 (m, 2H, Ar, A), 7.69–7.71 (m, 1H+4H, Ar, A, B),

ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 18 of 42

7.73 (d, 3J = 7.8 Hz, 1H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 22.4 (1JCH = 165 Hz, CH2), 33.1 (C), 35.6 (1JCH = 166 Hz, CH), 43.4 (1JCH = 139 Hz, CH2), 54.91 (1JCH = 144 Hz, CH3O), 108.57 (CH), 113.9 (2×CH), 120.6 (CH), 121.3 (CH), 126.30 (CH), 126.33 (CH), 126.68 (2×CH), 126.72 (2×CH), 127.17 (C), 128.1 (C), 128.48 (2×CH), 128.6 (2×CH), 130.1 (2×CH), 133.9 (C), 139.8 (C), 140.2 (C), 142.7 (C), 158.8 (C), 176.1 (CO). B:

13

C NMR (150 MHz,

CDCl3) δ = 22.2 (1JCH = 165 Hz, CH2), 33.9 (C), 38.1 (1JCH = 163 Hz, CH), 43.0 (1JCH = 139 Hz, CH2), 54.87 (1JCH = 144 Hz, CH3O), 108.56 (CH), 113.8 (2×CH), 118.0 (CH), 121.7 (CH), 126.5 (CH), 126.8 (2×CH), 126.9 (CH), 127.15 (2×CH), 128.2 (C), 128.45 (2×CH), 128.6 (2×CH), 129.5 (2×CH), 130.5 (C), 133.3 (C), 139.6 (C), 140.6 (C), 142.2 (C), 158.7 (C), 173.4 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C30H26NO2+ 432.1958; Found 432.1952. 1'-(4-Methoxybenzyl)-2-(naphthalen-1-yl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1h)

was obtained from S1h (570 mg, 1.46 mmol). Reaction time 2.5 h. Yield 540 mg (91%); orange solid, mp 137–138 °C; dr 86:14; Rf = 0.45 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 2.25 (dd, 2J = 4.6, 3J = 8.8 Hz, 1H, CH2, B), 2.30 (dd, 2J = 4.5, 3J = 8.0 Hz, 1H, CH2, A), 2.54 (dd, 2J = 4.6, 3J = 9.0 Hz, 1H, CH2, A), 2.68 (dd, 2J = 4.7, 3J = 8.5 Hz, 1H, CH2, B), 3.49 (dd, 3J = 8.8, 3J = 8.5 Hz, 1H, CH, B), 3.74 (s, 3H, CH3O, B), 3.77 (dd, 3J = 9.0, 3J = 8.0 Hz, 1H, CH, A), 3.80 (s, 3H, CH3O, A), 4.45 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.92 (d, 2J = 15.4 Hz, 1H, CH2, A), 4.96 (d, 2J = 15.6 Hz, 1H, CH2, B), 5.31 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.97 (dd, 3J = 7.6, 4J = 0.8 Hz, 1H, Ar, A), 6.44–6.47 (m, 1H, Ar, A), 6.71–6.74 (m, 2H, Ar, B), 6.77 (d, 3J = 7.8 Hz, 1H, Ar, A), 6.87–6.93 (m, 1H+3H, Ar, A, B), 6.98–7.00 (m, 2H, Ar, A), 7.13–7.18 (m, 2H, Ar, B), 7.14–7.27 (m, 1H, Ar, A), 7.26–7.32 (m, 2H, Ar, B), 7.34–7.37 (m, 1H, Ar, A), 7.42–7.45 (m, 2H, Ar, A), 7.49–7.52 (m, 2H, Ar, B), 7.54 (dd, 3J = 8.0, 3J = 7.2 Hz, 1H, Ar, A), 7.60 (dd, 3J = 8.0, 3J = 7.2 Hz, 1H, Ar, B), 7.62–7.63 (m, 1H, Ar, A), 7.67 (br.d, 3J = 8.5 Hz, 1H, Ar, A), 7.72–7.73 (m, 1H, Ar, B), 7.77 (br.d, 3J = 8.1 Hz, 1H, Ar, A), 7.82 (br.d, 3J = 8.1 Hz, 1H, Ar, A), 7.87 (br.d, 3J = 8.2 Hz, 1H, Ar, B), 7.91 (br.d, 3J = 8.1 Hz, 1H, Ar, B). A: 13

C NMR (150 MHz, CDCl3) δ = 21.7 (1JCH = 165 Hz, CH2), 33.3 (C), 34.3 (1JCH = 166 Hz, CH),

43.2 (1JCH = 139 Hz, CH2), 54.9 (1JCH = 144 Hz, CH3O), 108.4 (CH), 113.9 (2×CH), 119.3 (CH), 121.1 (CH), 123.2 (CH), 124.8 (CH), 125.6 (CH), 125.8 (CH), 126.1 (CH), 126.2 (CH), 126.9 (C), 128.08 (2×CH), 128.2 (C), 128.33 (2×CH), 131.6 (C), 132.9 (C), 133.1 (C), 142.2 (C), 158.8 (C), 176.1 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 21.8 (1JCH = 165 Hz, CH2), 33.2 (C), 35.9 (1JCH = 163 Hz, CH), 42.8 (1JCH = 139 Hz, CH2), 54.8 (1JCH = 144 Hz, CH3O), 108.6 (CH), 113.5 (2×CH), 118.1 (CH), 121.8 (CH), 123.1 (CH), 125.0 (CH), 125.1 (CH), 126.0 (CH), 126.7 (CH), 126.8 (CH), 127.86 (CH), 127.94 (C), 128.05 (C), 128.29 (2×CH), 128.6 (CH), 130.0 (C), 131.4

ACS Paragon Plus Environment

Page 19 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

(C), 133.2 (C), 142.4 (C), 158.5 (C), 173.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C28H24NO2+ 406.1802; Found 406.1803. 2-(1,3-Benzodioxol-5-yl)-1'-(4-methoxybenzyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one (1i) was obtained from S1i (370 mg, 0.961 mmol). Reaction time 2.5 h. Yield 320 mg (83%); yellow oil; dr 64:36; Rf = 0.40 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 2.00 (dd, 2J = 4.4, 3J = 7.9 Hz, 1H, CH2, A), 2.08 (dd, 2J = 4.9, 3J = 9.0 Hz, 1H, CH2, B), 2.26 (dd, 2J = 4.4, 3J = 9.1 Hz, 1H, CH2, A), 2.42 (dd, 2J = 4.9, 3J = 8.5 Hz, 1H, CH2, B), 3.14 (dd, 3J = 9.0, 3J = 8.5 Hz, 1H, CH, B), 3.37 (dd, 3J = 9.1, 3J = 7.9 Hz, 1H, CH, A), 3.74 (s, 3H, CH3O, B), 3.76 (s, 3H, CH3O, A), 4.82 (d, 2J = 15.4 Hz, 1H, CH2, B), 4.90 (d, 2J = 15.4 Hz, 1H, CH2, B), 4.97 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.03 (d, 2J = 15.4 Hz, 1H, CH2, A), 5.87–5.88 (m, 2H, OCH2O, B), 5.89–5.90 (m, 2H, OCH2O, A), 6.18 (br.d, 3J = 7.5 Hz, 1H, Ar, A), 6.69 (br.s, 1H, Ar, A), 6.73–6.75 (m, 3H, Ar, B), 6.76 (br.s, 1H, Ar, B), 6.76–6.78 (m, 1H, Ar, B), 6.79–6.80 (m, 1H, Ar, B), 6.84–6.89 (m, 4H, Ar, A), 6.90–6.91 (m, 2H, Ar, A), 6.94–6.96 (m, 1H, Ar, B), 7.03–7.06 (m, 1H, Ar, B), 7.07–7.10 (m, 1H, Ar, A), 7.18–7.20 (m, 1H, Ar, B), 7.23–7.24 (m, 2H, Ar, B), 7.33–7.34 (m, 2H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 22.5 (1JCH = 165 Hz, CH2), 33.1 (C), 35.6 (1JCH = 165 Hz, CH), 43.2 (1JCH = 139 Hz, CH2), 54.82 (1JCH = 144 Hz, CH3O), 100.8 (1JCH = 174 Hz, OCH2O), 107.7 (CH), 108.5 (CH), 110.0 (CH), 113.8 (2×CH), 120.5 (CH), 121.2 (CH), 122.7 (CH), 126.1 (CH), 127.1 (C), 128.06 (C), 128.4 (2×CH), 128.53 (C), 142.7 (C), 146.5 (C), 147.3 (C), 158.7 (C), 176.0 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 22.2 (1JCH = 165 Hz, CH2), 33.5 (C), 38.1 (1JCH = 162 Hz, CH), 42.9 (1JCH = 139 Hz, CH2), 54.79 (1JCH = 144 Hz, CH3O), 100.7 (1JCH = 174 Hz, OCH2O), 107.5 (CH), 108.4 (CH), 109.4 (CH), 113.7 (2×CH), 117.8 (CH), 121.5 (CH), 122.4 (CH), 126.3 (CH), 128.07 (C), 128.18 (C), 128.46 (2×CH), 130.4 (C), 142.1 (C), 146.4 (C), 147.1 (C), 158.6 (C), 173.4 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H22NO4+ 400.1543; Found 400.1553. 1'-(4-Methoxybenzyl)-2-(3,4,5-trimethoxyphenyl)spiro[cyclopropane-1,3'-indol]-2'(1'H)one (1j) was obtained from S1j (395 mg, 0.917 mmol). Reaction time 2.5 h. Yield 360 mg (88%); yellow viscous oil; dr 65:35; Rf = 0.16 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 1.98 (dd, 2J = 4.4, 3J = 7.9 Hz, 1H, CH2, A), 2.05 (dd, 2J = 4.8, 3J = 9.1 Hz, 1H, CH2, B), 2.20 (dd, 2J = 4.4, 3J = 9.2 Hz, 1H, CH2, A), 2.38 (dd, 2J = 4.8, 3J = 8.6 Hz, 1H, CH2, B), 3.08 (dd, 3J = 9.1, 3J = 8.6 Hz, 1H, CH, B), 3.32 (dd, 3J = 9.2, 3J = 7.9 Hz, 1H, CH, A), 3.63 (s, 3H, CH3O, B), 3.64 (s, 6H, CH3O, B), 3.68 (s, 6H, CH3O, A), 3.75 (s, 3H, CH3O, A), 3.795 (s, 3H, CH3O, A), 3.801 (s, 3H, CH3O, B), 4.68 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.81 (d, 2J = 15.5 Hz, 1H, CH2, A), 4.84 (d, 2J = 15.6 Hz, 1H, CH2, B), 5.00 (d, 2J = 15.5 Hz, 1H, CH2, A), 6.12 (br.d, 3J = 7.5 Hz, 1H, Ar, A), 6.39 (s, 2H, Ar, A), 6.54 (s, 2H, Ar, B), 6.63–6.66 (m, 1H, ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 20 of 42

Ar, A), 6.71–6.73 (m, 2H, Ar, B), 6.77–6.79 (m, 3H+1H, Ar, A, B), 6.88–6.90 (m, 1H, Ar, B), 6.94–6.97 (m, 1H, Ar, B), 6.98–7.00 (m, 1H, Ar, A), 7.08–7.11 (m, 1H, Ar, B), 7.11–7.13 (m, 2H, Ar, B), 7.23–7.24 (m, 2H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 22.4 (1JCH = 165 Hz, CH2), 32.8 (C), 35.8 (1JCH = 163 Hz, CH), 43.0 (1JCH = 139 Hz, CH2), 54.53 (1JCH = 144 Hz, CH3O), 55.5 (1JCH = 144 Hz, 2×CH3O), 60.3 (1JCH = 144 Hz, CH3O), 106.6 (2×CH), 108.3 (CH), 113.5 (2×CH), 120.3 (CH), 121.0 (CH), 126.0 (CH), 126.8 (C), 127.8 (C), 128.18 (2×CH), 130.2 (C), 136.9 (C), 142.3 (C), 152.5 (2×C), 158.5 (C), 175.8 (CO). B: 13C NMR (150 MHz, CDCl3)

δ = 22.2 (1JCH = 164 Hz, CH2), 33.4 (C), 38.4 (1JCH = 164 Hz, CH), 42.6 (1JCH = 139 Hz, CH2), 54.52 (1JCH = 144 Hz, CH3O), 55.4 (1JCH = 144 Hz, 2×CH3O), 60.2 (1JCH = 144 Hz, CH3O), 106.0 (2×CH), 108.2 (CH), 113.4 (2×CH), 117.7 (CH), 121.4 (CH), 126.2 (CH), 128.0 (C), 128.16 (2×CH), 128.4 (C), 129.8 (C), 136.6 (C), 141.9 (C), 152.2 (2×C), 158.4 (C), 173.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C27H27NO5+ 446.1962; Found 446.1964. 1'-(4-Methoxybenzyl)-2-(thien-2-yl)spiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1k)

was

obtained from S1k (547 mg, 1.58 mmol). Reaction time 2.5 h. Yield 490 mg (86%); yellow oil; dr 68:32; Rf =0.44 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 2.12 (dd, 2J = 4.5, 3J = 7.6 Hz, 1H, CH2, A), 2.20 (dd, 2J = 4.9, 3J = 9.0 Hz, 1H, CH2, B), 2.40 (dd, 2J = 4.5, 3J = 9.2 Hz, 1H, CH2, A), 2.49 (dd, 2J = 4.9, 3J = 8.2 Hz, 1H, CH2, B), 3.26 (dd, 3J = 9.0, 3

J = 8.2 Hz, 1H, CH, B), 3.44 (dd, 3J = 9.2, 3J = 7.6 Hz, 1H, CH, A), 3.74 (s, 3H, CH3O, B), 3.76

(s, 3H, CH3O, A), 4.83 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.94 (d, 2J = 15.5 Hz, 1H, CH2, A), 4.97 (d, 2J = 15.6 Hz, 1H, CH2, B), 5.06 (d, 2J = 15.5 Hz, 1H, CH2, A), 6.34 (br.d, 3J = 7.5 Hz, 1H, Ar, A), 6.78–6.80 (m, 1H, Ar, A), 6.87–6.89 (m, 2H, Ar, A), 6.91–6.94 (m, 2H+1H, Ar, A, B), 6.96–6.97 (m, 3H, Ar, B), 6.98–7.00 (m, 1H, Ar, A), 7.03–7.04 (m, 1H, Ar, B), 7.05–7.07 (m, 1H, Ar, B), 7.12–7.15 (m, 1H+1H, Ar, A, B), 7.19–7.20 (m, 1H, Ar, A), 7.21–7.23 (m, 2H, Ar, B), 7.27–7.28 (m, 2H, Ar, B), 7.35–7.36 (m, 2H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 23.4 (1JCH = 165 Hz, CH2), 29.9 (1JCH = 169 Hz, CH), 33.7 (C), 43.2 (1JCH = 139 Hz, CH2), 54.74 (1JCH = 144 Hz, CH3O), 108.52 (CH), 113.8 (2×CH), 120.0 (CH), 121.3 (CH), 125.0 (CH), 126.4 (CH), 126.49 (CH), 126.50 (C), 127.1 (CH), 127.9 (C), 128.3 (2×CH), 138.5 (C), 142.6 (C), 158.7 (C), 175.3 (CO). B:

13

C NMR (150 MHz, CDCl3) δ = 23.3 (1JCH = 165 Hz, CH2), 32.3

(1JCH = 166 Hz, CH), 33.9 (C), 42.9 (1JCH = 139 Hz, CH2), 54.72 (1JCH = 144 Hz, CH3O), 108.49 (CH), 113.7 (2×CH), 117.8 (CH), 121.5 (CH), 124.4 (CH), 126.3 (CH), 126.52 (CH), 126.8 (CH), 128.0 (C), 128.4 (2×CH), 129.6 (C), 137.6 (C), 142.1 (C), 158.6 (C), 172.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C22H20NO2S+ 362.1209; Found 362.1213.

ACS Paragon Plus Environment

Page 21 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

5-Methyl-1'-(4-methoxybenzyl)-2-phenylspiro[cyclopropane-1,3'-indol]-2'(1'H)-one (1l) was obtained from S1l (5.3 g, 15 mmol). Reaction time 2.5 h. Yield 4.72 g (85%); white foam; dr 65:35; Rf =0.50 (petroleum ether – ethyl acetate, 2:1). 1H NMR (600 MHz, CDCl3) δ = 2.05 (dd, 2

J = 4.4, 3J = 8.0 Hz, 1H, CH2, A), 2.04 (s, 3H, CH3, A), 2.12 (dd, 2J = 4.9, 3J = 9.1 Hz, 1H, CH2,

B), 2.29 (dd, 2J = 4.4, 3J = 9.2 Hz, 1H, CH2, A), 2.39 (s, 3H, CH3, B), 2.50 (dd, 2J = 4.9, 3J = 8.6 Hz, 1H, CH2, B), 3.20 (dd, 3J = 9.1, 3J = 8.6 Hz, 1H, CH, B), 3.44 (dd, 3J = 9.2, 3J = 8.0 Hz, 1H, CH, A), 3.78 (s, 3H, CH3O, B), 3.81 (s, 3H, CH3O, A), 4.81 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.84 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.97 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.03 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.81–5.82 (m, 1H, Ar, A), 6.72 (d, 3J = 7.9 Hz, 1H, Ar, A), 6.75 (d, 3J = 7.9 Hz, 1H, Ar, B), 6.83–6.85 (m, 3H, Ar, B), 6.87–6.89 (m, 1H, Ar, A), 6.90–6.92 (m, 2H, Ar, A), 7.01– 7.02 (m, 1H, Ar, B), 7.19–7.22 (m, 2H, Ar, B), 7.23–7.25 (m, 2H, Ar, A), 7.28–7.40 (m, 5H+5H, Ar, A, B). A:

13

C NMR (150 MHz, CDCl3) δ = 20.8 (CH3), 22.4 (CH2), 33.1 (C), 35.8 (CH),

43.5 (CH2), 55.10 (CH3O), 108.3 (CH), 114.0 (2×CH), 121.6 (CH), 126.6 (CH), 127.2 (CH), 127.5 (C), 128.2 (2×CH), 128.4 (C), 128.52 (2×CH), 129.9 (2×CH), 130.7 (C), 135.1 (C), 140.5 (C), 158.9 (C), 176.3 (CO). B:

13

C NMR (150 MHz, CDCl3) δ = 21.0 (CH3), 22.1 (CH2), 33.7

(C), 38.3 (CH), 43.2 (CH2), 55.07 (CH3O), 108.4 (CH), 113.9 (2×CH), 118.9 (CH), 126.8 (CH), 127.1 (CH), 127.8 (2×CH), 128.50 (C), 128.7 (2×CH), 129.2 (2×CH), 131.3 (C), 130.8 (C), 134.4 (C), 140.1 (C), 158.8 (C), 173.6 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H24NO2+ 370.1802; Found 370.1808. 5-Fluoro-1'-(4-methoxybenzyl)-2-phenylspiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1m)

was obtained from S1m (3.40 g, 9.5 mmol). Reaction time 2.5 h. Yield 3.05 g (86%); yellow foam; dr 74:26; Rf =0.63 (petroleum ether – ethyl acetate, 2:1). 1H NMR (600 MHz, CDCl3) δ = 2.06 (dd, 2J = 4.5, 3J = 8.0 Hz, 1H, CH2, A), 2.12 (dd, 2J = 5.0, 3J = 9.1 Hz, 1H, CH2, B), 2.32 (dd, 2J = 4.5, 3J = 9.2 Hz, 1H, CH2, A), 2.53 (dd, 2J = 5.0, 3J = 8.7 Hz, 1H, CH2, B), 3.18 (dd, 3J = 9.1, 3J = 8.7 Hz, 1H, CH, B), 3.47 (dd, 3J = 9.2, 3J = 8.0 Hz, 1H, CH, A), 3.78 (s, 3H, CH3O, B), 3.80 (s, 3H, CH3O, A), 4.79 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.83 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.94 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.01 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.73 (dd, 3J = 8.6, 4J = 2.6 Hz, 1H, Ar, A), 6.69 (dd, 3J = 8.6, 4J = 4.3 Hz, 1H, Ar, A), 6.71–6.76 (m, 1H+2H, Ar, A, B), 6.82–6.85 (m, 2H, Ar, B), 6.86–6.89 (m, 1H, Ar, B), 6.89–6.92 (m, 2H, Ar, A), 7.16–7.18 (m, 2H, Ar, B), 7.21–7.22 (m, 2H, Ar, A), 7.28–7.31 (m, 2H+4H, Ar, A, B), 7.32–7.35 (m, 2H+1H, Ar, A, B), 7.35–7.36 (m, 1H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 22.9 (1JCH = 165 Hz, CH2), 33.5 (4JCF = 2 Hz, C), 36.4 (1JCH = 165 Hz, CH), 43.7 (1JCH = 139 Hz, CH2), 55.14 (1JCH = 144 Hz, CH3O), 108.7 (2JCF = 26 Hz, CH), 109.0 (3JCF = 8 Hz, CH), 112.5 (2JCF = 24 Hz, CH), 114.1 (2×CH), 127.6 (CH), 128.0 (C), 128.5 (2×CH), 128.6 (2×CH), 129.3 (3JCF = 9 Hz, ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 22 of 42

C), 129.7 (2×CH), 134.4 (C), 138.7 (C), 158.3 (1JCF = 239 Hz, C), 159.0 (C), 176.1 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 22.4 (1JCH = 165 Hz, CH2), 34.1 (4JCF = 2 Hz, C), 38.9 (1JCH = 164 Hz, CH), 43.3 (1JCH = 139 Hz, CH2), 55.11 (1JCH = 144 Hz, CH3O), 106.3 (2JCF = 25 Hz, CH), 109.1 (3JCF = 8 Hz, CH), 112.7 (2JCF = 23 Hz, CH), 114.0 (2×CH), 127.4 (CH), 127.7 (2×CH), 128.1 (C), 128.7 (2×CH), 129.2 (2×CH), 132.5 (3JCF = 9 Hz, C), 133.9 (C), 138.3 (C), 158.9 (C), 159.0 (1JCF = 239 Hz, C), 173.3 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H21FNO2+ 374.1551; Found 374.1560. Ethyl 4-(5'-fluoro-1'-(4-methoxybenzyl)-2'-oxo-1',2'-dihydrospiro[cyclopropane-1,3'-indol]2-yl)benzoate (1n) was obtained from S1n (6.87 g, 16 mmol). Reaction time 2.5 h. Yield 4.27 g (60%); yellow foam; dr 65:35; Rf =0.29 (petroleum ether – ethyl acetate, 3:1). 1H NMR (600 MHz, CDCl3) δ = 1.39 (t, 3J = 7.2 Hz, 3H, CH3, A), 141 (t, 3J = 7.2 Hz, 3H, CH3, A), 2.06 (dd, 2J = 4.8, 3J = 8.1 Hz, 1H, CH2, A), 2.15 (dd, 2J = 5.1, 3J = 9.0 Hz, 1H, CH2, B), 2.33 (dd, 2J = 4.8, 3

J = 9.1 Hz, 1H, CH2, A), 2.54 (dd, 2J = 5.1, 3J = 8.6 Hz, 1H, CH2, B), 3.18 (dd, 3J = 9.0, 3J = 8.6

Hz, 1H, CH, B), 3.44 (dd, 3J = 9.0, 3J = 8.1 Hz, 1H, CH, A), 3.77 (s, 3H, CH3O, B), 3.80 (s, 3H, CH3O, A), 4.39 (q, 3J = 7.2 Hz, 2H+2H, CH2O, A, B), 4.75 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.80 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.90 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.01 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.70 (dd, 3J = 8.5, 4J = 2.5 Hz, 1H, Ar, A), 6.68 (dd, 3J = 8.5, 4J = 4.4 Hz, 1H, Ar, A), 6.71–6.77 (m, 1H+2H, Ar, A, B), 6.80–6.84 (m, 2H, Ar, B), 6.84–6.86 (m, 1H, Ar, B), 6.86–6.90 (m, 2H, Ar, A), 7.11–7.15 (m, 2H, Ar, B), 7.26–7.28 (m, 4H, Ar, A), 7.39–7.41 (m, 2H, Ar, B), 8.00–8.03 (m, 2H+2H, Ar, A, B). A:

13

C NMR (150 MHz, CDCl3) δ = 13.9 (1JCH = 127 Hz,

CH3), 22.12 (1JCH = 165 Hz, CH2), 33.4 (C), 35.8 (1JCH = 166 Hz, CH), 43.4 (1JCH = 139 Hz, CH2), 54.77 (1JCH = 144 Hz, CH3O), 60.7 (1JCH = 147 Hz, CH2O), 108.3 (2JCF = 26 Hz, CH), 108.96 (3JCF = 7 Hz, CH), 112.6 (2JCF = 24 Hz, CH), 113.9 (2×CH), 127.6 (C), 128.3 (2×CH), 128.5 (3JCF = 9 Hz, C), 129.10 (C), 129.43 (2×CH), 129.44 (2×CH), 138.6 (C), 139.4 (C), 158.0 (1JCF = 239 Hz, C), 158.8 (C), 165.7 (CO2Et), 175.4 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 14.0 (1JCH = 127 Hz, CH3), 22.05 (1JCH = 165 Hz, CH2), 34.1 (C), 38.0 (1JCH = 162 Hz, CH), 43.0 (1JCH = 139 Hz, CH2), 54.75 (1JCH = 144 Hz, CH3O), 60.5 (1JCH = 148 Hz, CH2O), 106.2 (2JCF = 25 Hz, CH), 109.01 (3JCF = 7 Hz, CH), 112.7 (2JCF = 24 Hz, CH), 113.7 (2×CH), 127.7 (C), 128.4 (2×CH), 128.8 (2×CH), 129.05 (C), 129.5 (2×CH), 131.8 (3JCF = 9 Hz, C), 138.1 (C), 139.1 (C), 158.7 (C), 158.7 (1JCF = 240 Hz, C), 165.9 (CO2Et), 172.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C27H25FNO4+ 446.1762; Found 446.1767. 5-Chloro-1'-(4-methoxybenzyl)-2-phenylspiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1o)

was obtained from S1o (4.20 g, 11.2 mmol). Reaction time 2.5 h. Yield 3.54 g (81%); yellow

ACS Paragon Plus Environment

Page 23 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

foam; dr 69:31; Rf =0.65 (petroleum ether – ethyl acetate, 2:1). 1H NMR (600 MHz, CDCl3) δ = 2.07 (dd, 2J = 4.6, 3J = 7.9 Hz, 1H, CH2, A), 2.13 (dd, 2J = 5.0, 3J = 9.1 Hz, 1H, CH2, B), 2.32 (dd, 2J = 4.6, 3J = 9.2 Hz, 1H, CH2, A), 2.53 (dd, 2J = 5.0, 3J = 8.8 Hz, 1H, CH2, B), 3.20 (dd, 3J = 9.1, 3J = 8.8 Hz, 1H, CH, B), 3.47 (dd, 3J = 9.2, 3J = 7.9 Hz, 1H, CH, A), 3.77 (s, 3H, CH3O, B), 3.80 (s, 3H, CH3O, A), 4.78 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.82 (d, 2J = 15.5 Hz, 1H, CH2, B), 4.94 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.01 (d, 2J = 15.5 Hz, 1H, CH2, A), 5.93 (dd, 4J = 2.1, 5J = 0.4 Hz, 1H, Ar, A), 6.70 (br.d, 3J = 8.4 Hz, 1H, Ar, A), 6.73 (br.d, 3J = 8.4 Hz, 1H, Ar, B), 6.82–6.84 (m, 2H, Ar, B), 6.89–6.91 (m, 2H, Ar, A), 6.96 (dd, 4J = 2.1, 5J = 0.4 Hz, 1H, Ar, B), 7.01 (dd, 3J = 8.3, 4J = 2.1 Hz, 1H, Ar, A), 7.14 (dd, 3J = 8.3, 4J = 2.1 Hz, 1H, Ar, B), 7.14–7.17 (m, 2H, Ar, B), 7.20–7.22 (m, 2H, Ar, A), 7.27–7.29 (m, 2H, Ar, A), 7.29–7.32 (m, 4H, Ar, B), 7.33–7.36 (m, 3H+1H, Ar, A, B). A:

13

C NMR (150 MHz, CDCl3) δ = 22.9 (1JCH = 165 Hz,

CH2), 33.2 (C), 36.5 (1JCH = 165 Hz, CH), 43.6 (1JCH = 139 Hz, CH2), 55.2 (1JCH = 144 Hz, CH3O), 109.5 (CH), 114.1 (2×CH), 121.0 (CH), 126.2 (CH), 126.8 (C), 127.7 (CH), 127.8 (C), 128.45 (2×CH), 128.53 (2×CH), 129.3 (C), 129.7 (2×CH), 134.4 (C), 141.4 (C), 159.0 (C), 175.9 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 22.4 (1JCH = 165 Hz, CH2), 33.8 (C), 38.9 (1JCH = 162 Hz, CH), 43.3 (1JCH = 139 Hz, CH2), 55.1 (1JCH = 144 Hz, CH3O), 109.6 (CH), 114.0 (2×CH), 118.6 (CH), 126.4 (CH), 127.2 (C), 127.4 (CH), 127.88 (2×CH), 127.92 (C), 128.7 (2×CH), 129.2 (2×CH), 132.5 (C), 133.8 (C), 140.9 (C), 158.9 (C), 173.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H21ClNO2+ 390.1255; Found 390.1264. 5-Bromo-1'-(4-methoxybenzyl)-2-phenylspiro[cyclopropane-1,3'-indol]-2'(1'H)-one

(1p)

was obtained from S1p (2.99 g, 7.14 mmol). Reaction time 2.5 h. Yield 2.36 g (76%); yellow foam; dr 69:31; Rf =0.60 (petroleum ether – ethyl acetate, 2:1). 1H NMR (600 MHz, CDCl3) δ = 2.06 (dd, 2J = 4.6, 3J = 8.0 Hz, 1H, CH2, A), 2.13 (dd, 2J = 5.1, 3J = 9.1 Hz, 1H, CH2, B), 2.29 (dd, 2J = 4.6, 3J = 9.2 Hz, 1H, CH2, A), 2.51 (dd, 2J = 5.1, 3J = 8.7 Hz, 1H, CH2, B), 3.19 (dd, 3J = 9.1, 3J = 8.7 Hz, 1H, CH, B), 3.44 (dd, 3J = 9.1, 3J = 8.0 Hz, 1H, CH, A), 3.77 (s, 3H, CH3O, B), 3.80 (s, 3H, CH3O, A), 4.77 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.79 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.91 (d, 2J = 15.5 Hz, 1H, CH2, A), 4.99 (d, 2J = 15.5 Hz, 1H, CH2, A), 6.02 (dd, 4J = 2.0, 5J = 0.4 Hz, 1H, Ar, A), 6.64 (br.d, 3J = 8.3 Hz, 1H, Ar, A), 6.67 (br.d, 3J = 8.3 Hz, 1H, Ar, B), 6.80–6.82 (m, 2H, Ar, B), 6.87–6.89 (m, 2H, Ar, A), 7.08 (dd, 4J = 2.0, 5J = 0.4 Hz, 1H, Ar, B), 7.11–7.14 (m, 2H, Ar, B), 7.15 (dd, 3J = 8.3, 4J = 2.0 Hz, 1H, Ar, A), 7.18–7.20 (m, 2H, Ar, A), 7.24–7.26 (m, 2H, Ar, A), 7.27–7.32 (m, 4H, Ar, B), 7.33–7.35 (m, 3H+1H, Ar, A, B). A: 13C NMR (150 MHz, CDCl3) δ = 22.7 (CH2), 33.0 (C), 36.4 (CH), 43.4 (CH2), 55.0 (CH3O), 109.85 (CH), 113.96 (C), 114.00 (2×CH), 123.6 (CH), 127.5 (CH), 127.6 (C), 127.7 (CH), 128.3 (2×CH), 128.4 (2×CH), 129.5 (C), 129.6 (2×CH), 134.2 (C), 141.7 (C), 158.9 (C), 175.6 (CO). ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

B: 13C NMR (150 MHz, CDCl3) δ = 22.3 (CH2), 33.6 (C), 38.8 (CH), 43.1 (CH2), 54.9 (CH3O), 109.91 (CH), 113.8 (2×CH), 114.3 (C), 121.2 (CH), 127.2 (CH), 128.1 (C), 128.46 (C), 128.50 (2×CH), 129.0 (2×CH), 129.12 (2×CH), 132.8 (CH), 133.7 (C), 141.2 (C), 158.8 (C), 172.8 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C24H21BrNO2+ 434.0750; Found 434.0761. General procedure for the synthesis of spiro[pyrrolidone-3,3'-oxindole] 2. Solution of cyclopropane 1 (0.20 mmol, 1.0 equiv) in dry DMF (2.0 mL, 0.1 M), KNCO (33 mg, 0.40 mmol, 2.0 equiv) and triethylamine hydrochloride (28 mg, 0.20 mmol, 1.0 equiv) was placed in microwave vessel. The reaction mixture was stirred (800 rpm) under the heating by microwave irradiation at 150 °C for time specified, then it was cooled down to ambient temperature and an extra portion of KNCO (33 mg, 0.40 mmol, 2.0 equiv) was added (excluding synthesis of 2m-p). The resulting mixture was further heated under microwave irradiation at 150°C for time specified, cooled to ambient temperature, poured into water (20 mL) and extracted with ethyl acetate (3×20 mL). Combined organic layers were washed with brine (5×10 mL), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by column chromatography on conventional or neutralized (2c-e,i-k,s-u) silica gel (petroleum ether – ethyl acetate). Preparation of neutralized silica gel: In Erlenmeyer flask, silica gel (ca. 12 g), petroleum ether (90 mL), ethyl acetate (5 mL) and triethylamine (1 mL) were mixed. The suspension was then shaken vigorously and left overnight. The column was packed with the resulting silica gel slurry. In order to remove leftover polar solvent, petroleum ether was passed through the column (total volume is approximately 8–10 volumes of silica gel). 1-(4-Methoxybenzyl)-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2a) was obtained from 1a (424 mg, 1.20 mmol). Reaction time 4+6 h. Yield 294 mg (62%); white solid, mp 216–217 °C; dr 52:48; Rf = 0.38 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.41 (dd, 2J = 13.3, 3J = 8.2 Hz, 1H, CH2, A), 2.81 (dd, 2J = 13.5, 3J = 7.5 Hz, 1H, CH2, B), 2.88 (dd, 2J = 13.5, 3J = 8.3 Hz, 1H, CH2, B), 3.11 (dd, 2J = 13.4, 3J = 7.2 Hz, 1H, CH2, A), 3.76 (s, 3H, CH3O), 3.77 (s, 3H, CH3O), 4.83 (d, 2J = 15.6 Hz, 1H, CH2), 4.84 (d, 2J = 15.6 Hz, 1H, CH2), 4.92 (d, 2J = 15.6 Hz, 1H, CH2), 4.98 (d, 2J = 15.6 Hz, 1H, CH2), 5.10 (dd, 3J = 8.3, 3J = 7.5 Hz, 1H, CH, B), 5.34 (dd, 3J = 8.2, 3J = 7.2 Hz, 1H, CH, A), 6.74–6.77 (m, 2H, Ar), 6.81–6.86 (m, 4H, Ar), 6.89 (br.s, 1H, NH), 6.95 (br.s, 1H, NH), 7.04–7.09 (m, 2H, Ar), 7.17– 7.19 (m, 1H, Ar), 7.19–7.23 (m, 2H, Ar), 7.24–7.29 (m, 4H, Ar), 7.34–7.39 (m, 3H, Ar), 7.41– 7.45 (m, 6H, Ar), 7.51–7.53 (m, 2H, Ar).

13

C NMR (150 MHz, CDCl3) δ = 41.4 (CH2), 42.1

(CH2), 43.4 (CH2), 43.6 (CH2), 55.20 (CH3O), 55.21 (CH3O), 55.4 (CH), 56.5 (CH), 58.5 (C), 58.6 (C), 109.6 (CH), 109.8 (CH), 114.2 (2×CH), 114.3 (2×CH), 122.5 (CH), 123.0 (CH), 123.2 (CH), 123.3 (CH), 125.8 (2×CH), 126.4 (2×CH), 127.3 (2×C), 128.3 (CH), 128.4 (3×CH), 128.5 ACS Paragon Plus Environment

Page 24 of 42

Page 25 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

(2×CH), 128.6 (C), 128.99 (CH), 129.02 (2×CH), 129.08 (CH), 129.11 (2×CH), 130.1 (C), 141.1 (C), 141.5 (C), 143.2 (C), 143.8 (C), 159.0 (C), 159.1 (C), 173.6 (CO), 173.8 (CO), 175.1 (CO), 175.5 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H23N2O3+ 399.1703; Found 399.1698. 1-(4-Methoxybenzyl)-5'-(p-tolyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2b) was obtained from 1b (77 mg, 0.21 mmol). Reaction time 2+4 h. Yield 57 mg (66%); yellowish solid, mp 195–196 °C; dr 51:49; Rf = 0.40 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.36 (CH3), 2.38 (CH3), 2.39 (dd, 2J = 13.4, 3J = 8.4 Hz, 1H, CH2, A), 2.77 (dd, 2J = 13.3, 3J = 7.4 Hz, 1H, CH2, B), 2.85 (dd, 2J = 13.3, 3J = 8.3 Hz, 1H, CH2, B), 3.09 (dd, 2J = 13.4, 3

J = 7.1 Hz, 1H, CH2, A), 3.75 (s, 3H, CH3O), 3.76 (s, 3H, CH3O), 4.81 (d, 2J = 15.6 Hz, 1H,

CH2), 4.83 (d, 2J = 15.7 Hz, 1H, CH2), 4.92 (d, 2J = 15.6 Hz, 1H, CH2), 4.98 (d, 2J = 15.7 Hz, 1H, CH2), 5.06 (dd, 3J = 8.3, 3J = 7.4 Hz, 1H, CH, B), 5.29 (dd, 3J = 8.4, 3J = 7.1 Hz, 1H, CH, A), 6.73–6.76 (m, 2H, Ar), 6.80–6.84 (m, 4H, Ar), 6.91 (br.s, 1H, NH), 6.98 (br.s, 1H, NH), 7.03–7.08 (m, 2H, Ar), 7.17–7.29 (m, 11H, Ar), 7.32–7.33 (m, 2H, Ar), 7.35–7.36 (m, 1H, Ar), 7.39–7.40 (m, 2H, Ar).

13

C NMR (150 MHz, CDCl3) δ = 21.0 (1JCH = 127 Hz, 2×CH3), 41.4

(1JCH = 138 Hz, CH2), 42.1 (1JCH = 138 Hz, CH2), 43.3 (1JCH = 138 Hz, CH2), 43.5 (1JCH = 138 Hz, CH2), 55.13 (1JCH = 144 Hz, 2×CH3O), 55.14 (1JCH = 140 Hz, CH), 56.2 (1JCH = 140 Hz, CH), 58.5 (C), 58.6 (C), 109.5 (CH), 109.6 (CH), 114.1 (2×CH), 114.2 (2×CH), 122.5 (CH), 122.9 (CH), 123.1 (CH), 123.3 (CH), 125.7 (2×CH), 126.3 (2×CH), 127.3 (2×C), 128.36 (2×CH), 128.41 (2×CH), 128.76 (C), 128.84 (CH), 128.9 (CH), 129.6 (2×CH), 129.7 (2×CH), 130.2 (C), 138.0 (C), 138.10 (C), 138.12 (C), 138.5 (C), 143.2 (C), 143.7 (C), 158.9 (C), 159.0 (C), 173.4 (CO), 173.5 (CO), 175.1 (CO), 175.6 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C26H25N2O3+ 413.1860; Found 413.1864. 1-(4-Methoxybenzyl)-5'-(4-methoxyphenyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)dione (2c) was obtained from 1c (73 mg, 0.19 mmol). Reaction time 2+2 h. Purification was performed on neutralized silica gel. Yield 45 mg (56%); orange solid, mp 223–224 °C; dr 51:49; Rf = 0.42 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.38 (dd, 2J = 13.3, 3J = 8.3 Hz, 1H, CH2, A), 2.77 (dd, 2J = 13.4, 3J = 7.4 Hz, 1H, CH2, B), 2.85 (dd, 2J = 13.4, 3

J = 8.3 Hz, 1H, CH2, B), 3.06 (dd, 2J = 13.3, 3J = 7.0 Hz, 1H, CH2, A), 3.75 (s, 3H, CH3O), 3.76

(s, 3H, CH3O), 3.81 (s, 3H, CH3O), 3.83 (s, 3H, CH3O), 4.81 (d, 2J = 15.6 Hz, 1H, CH2), 4.83 (d, 2

J = 15.6 Hz, 1H, CH2), 4.92 (d, 2J = 15.6 Hz, 1H, CH2), 4.98 (d, 2J = 15.6 Hz, 1H, CH2), 5.05

(dd, 3J = 8.3, 3J = 7.4 Hz, 1H, CH, B), 5.29 (dd, 3J = 8.3, 3J = 7.0 Hz, 1H, CH, A), 6.69 (br.s, 1H, NH), 6.74–6.76 (m, 2H+1H, Ar, NH), 6.81–6.84 (m, 4H, Ar), 6.93–6.96 (m, 4H, Ar), 7.04–7.08 (m, 2H, Ar), 7.19–7.22 (m, 3H, Ar), 7.24–7.28 (m, 4H, Ar), 7.34–7.37 (m, 3H, Ar), 7.43–7.45

ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 26 of 42

(m, 2H, Ar). 13C NMR (150 MHz, CDCl3) δ = 41.5 (1JCH = 138 Hz, CH2), 42.3 (1JCH = 138 Hz, CH2), 43.4 (1JCH = 138 Hz, CH2), 43.6 (1JCH = 138 Hz, CH2), 54.9 (1JCH = 144 Hz, CH), 55.16 (1JCH = 144 Hz, CH3O), 55.18 (1JCH = 144 Hz, CH3O), 55.28 (1JCH = 144 Hz, CH3O), 55.30 (1JCH = 144 Hz, CH3O), 55.9 (1JCH = 144 Hz, CH), 58.5 (C), 58.6 (C), 109.5 (CH), 109.7 (CH), 114.15 (2×CH), 114.21 (2×CH), 114.3 (2×CH), 114.4 (2×CH), 122.5 (CH), 122.9 (CH), 123.2 (CH), 123.3 (CH), 127.1 (2×CH), 127.3 (2×C), 127.7 (2×CH), 128.39 (2×CH), 128.44 (2×CH), 128.7 (C), 128.9 (CH), 129.0 (CH), 130.2 (C), 133.0 (C), 133.3 (C), 143.2 (C), 143.7 (C), 158.97 (C), 159.01 (C), 159.5 (C), 159.7 (C), 173.2 (CO), 173.3 (CO), 175.2 (CO), 175.6 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C26H25N2O4+ 429.1809; Found 429.1816. 5'-(4-Bromophenyl)-1-(4-methoxybenzyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2d) was obtained from 1d (78 mg, 0.18 mmol). Reaction time 2+2 h. Purification was performed on neutralized silica gel. Yield 41 mg (48%); orange solid, mp 199–200 °C; dr 53:47; Rf = 0.58 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.32 (dd, 2J = 13.3, 3J = 8.1 Hz, 1H, CH2, A), 2.77 (dd, 2J = 13.5, 3J = 8.0 Hz, 1H, CH2, B), 2.82 (dd, 2J = 13.5, 3

J = 7.6 Hz, 1H, CH2, B), 3.09 (dd, 2J = 13.3, 3J = 7.1 Hz, 1H, CH2, A), 3.75 (s, 3H, CH3O), 3.77

(s, 3H, CH3O), 4.80 (d, 2J = 15.6 Hz, 1H, CH2), 4.82 (d, 2J = 15.6 Hz, 1H, CH2), 4.91 (d, 2J = 15.6 Hz, 1H, CH2), 4.96 (d, 2J = 15.6 Hz, 1H, CH2), 5.05 (dd, 3J = 8.3, 3J = 7.4 Hz, 1H, CH, B), 5.29 (dd, 3J = 8.3, 3J = 7.0 Hz, 1H, CH, A), 6.73–6.76 (m, 2H, Ar), 6.79–6.84 (m, 4H, Ar), 7.04– 7.08 (m, 2H, Ar), 7.13–7.14 (m, 1H, Ar), 7.18 (br.s, 1H, NH), 7.19–7.26 (m, 6H+1H, Ar, NH), 7.30–7.33 (m, 3H, Ar), 7.37–7.38 (m, 2H, Ar), 7.51–7.55 (m, 4H, Ar). 1

1

13

C NMR (150 MHz,

1

CDCl3) δ = 41.1 ( JCH = 138 Hz, CH2), 41.9 ( JCH = 138 Hz, CH2), 43.4 ( JCH = 138 Hz, CH2), 43.6 (1JCH = 138 Hz, CH2), 54.9 (1JCH = 144 Hz, CH), 55.21 (1JCH = 144 Hz, CH3O), 55.23 (1JCH = 144 Hz, CH3O), 55.8 (1JCH = 144 Hz, CH), 58.3 (C), 58.5 (C), 109.7 (CH), 109.8 (CH), 114.2 (2×CH), 114.3 (2×CH), 122.1 (C), 122.3 (C), 122.5 (CH), 123.0 (CH), 123.2 (2×CH), 127.2 (2×C), 127.5 (2×CH), 128.1 (2×CH), 128.39 (2×CH), 128.44 (2×CH), 128.5 (C), 129.1 (CH), 129.2 (CH), 130.0 (C), 132.1 (2×CH), 132.2 (2×CH), 140.4 (C), 140.6 (C), 143.3 (C), 143.7 (C), 159.0 (C), 159.1 (C), 173.6 (CO), 173.7 (CO), 175.0 (CO), 175.4 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H22BrN2O3+ 477.0808; Found 477.0821. 4-[1-(4-Methoxybenzyl)-2,2'-dioxo-1,2-dihydrospiro[indole-3,3'-pyrrolidin]-5'yl]benzonitrile (2e) was obtained from 1e (71 mg, 0.19 mmol). Reaction time 2+1 h. Purification was performed on neutralized silica gel. Yield 32 mg (48%); orange solid, mp 184– 186 °C; dr 53:47; Rf = 0.46 (A), 0.39 (B) (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.30 (dd, 2J = 13.4, 3J = 8.1 Hz, 1H, CH2, A), 2.74 (dd, 2J = 13.6, 3J = 7.4 Hz,

ACS Paragon Plus Environment

Page 27 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

1H, CH2, B), 2.88 (dd, 2J = 13.6, 3J = 7.9 Hz, 1H, CH2, B), 3.14 (dd, 2J = 13.4, 3J = 7.4 Hz, 1H, CH2, A), 3.75 (s, 3H, CH3O), 3.77 (s, 3H, CH3O), 4.78 (d, 2J = 15.6 Hz, 1H, CH2), 4.79 (d, 2J = 15.6 Hz, 1H, CH2), 4.90 (d, 2J = 15.6 Hz, 1H, CH2), 4.95 (d, 2J = 15.6 Hz, 1H, CH2), 5.11–5.13 (m, 1H, CH), 5.35–5.37 (m, 1H, CH), 6.74–6.81 (m, 6H, Ar), 7.03–7.10 (m, 3H, Ar), 7.20–7.24 (m, 6H, Ar), 7.32–7.33 (m, 1H, Ar), 7.51–7.52 (m, 2H, Ar), 7.57–7.58 (m, 2H, Ar), 7.61 (br.s, 1H, NH), 7.63–7.65 (m, 2H, Ar), 7.66–7.67 (m, 2H, Ar), 7.70 (br.s, 1H, NH).

13

C NMR (150

MHz, CDCl3) δ = 40.6 (CH2), 41.5 (CH2), 43.4 (CH2), 43.6 (CH2), 55.1 (CH), 55.19 (CH3O), 55.21 (CH3O), 55.9 (CH), 58.2 (C), 58.4 (C), 109.7 (CH), 109.9 (CH), 112.07 (C), 112.11 (C), 114.2 (2×CH), 114.3 (2×CH), 118.3 (C), 118.4 (C), 122.5 (CH), 123.13 (CH), 123.15 (CH), 123.3 (CH), 126.5 (2×CH), 127.0 (2×CH, 2×C), 128.2 (C), 128.3 (2×CH), 128.4 (2×CH), 129.2 (CH), 129.3 (CH), 129.7 (C), 132.8 (2×CH), 132.9 (2×CH), 143.3 (C), 143.7 (C), 146.7 (C), 147.0 (C), 159.06 (C), 159.10 (C), 174.0 (CO), 174.1 (CO), 174.9 (CO), 175.3 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C26H22N3O3+ 424.1656; Found 424.1667. 5'-(Biphenyl-4-yl)-1-(4-methoxybenzyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2g) was obtained from 1g (86 mg, 0.20 mmol). Reaction time 2+4 h. Yield 53 mg (56%); yellow solid, mp 244–245 °C; dr 53:47; Rf = 0.38 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, DMSO-d6) δ = 2.31 (dd, 2J = 13.3, 3J = 8.1 Hz, 1H, CH2, A), 2.50 (dd, 2J = 13.3, 3J = 8.5 Hz, 1H, CH2, B), 2.83 (dd, 2J = 13.3, 3J = 7.3 Hz, 1H, CH2, B), 3.07 (dd, 2J = 13.3, 3J = 7.3 Hz, 1H, CH2, A), 3.71 (s, 3H, CH3O, B), 3.72 (s, 3H, CH3O, A), 4.78 (d, 2J = 15.7 Hz, 1H, CH2, B), 4.81 (d, 2J = 15.7 Hz, 1H, CH2, A), 4.90 (d, 2J = 15.7 Hz, 1H, CH2, A), 4.95 (d, 2J = 15.7 Hz, 1H, CH2, B), 5.17 (dd, 3J = 8.1, 3J = 7.3 Hz, 1H, CH, A), 5.26 (dd, 3J = 8.5, 3J = 7.3 Hz, 1H, CH, B), 6.87–6.90 (m, 2H+2H, Ar, A, B), 6.92–6.94 (m, 1H+1H, Ar, A, B), 7.01–7.04 (m, 1H, Ar, B), 7.07–7.10 (m, 1H, Ar, A), 7.22–7.32 (m, 3H+4H, Ar, A, B), 7.37–7.40 (m, 1H+1H, Ar, A, B), 7.47–7.50 (m, 2H+2H, Ar, A, B), 7.52–7.53 (m, 1H, Ar, A), 7.57–7.59 (m, 2H, Ar, A), 7.61– 7.62 (m, 2H, Ar, B), 7.69–7.71 (m, 2H+2H, Ar, A, B), 7.73–7.75 (m, 2H+2H, Ar, A, B), 8.91 (br.s, 1H, NH, B), 8.93 (br.s, 1H, NH, A). A: 13C NMR (150 MHz, DMSO-d6) δ = 41.1 (CH2), 42.2 (CH2), 54.4 (CH), 55.0 (CH3O), 58.36 (C), 109.3 (CH), 114.03 (2×CH), 122.7 (CH), 123.4 (CH), 126.7 (2×CH), 126.9 (2×CH), 126.69 (CH), 127.00 (2×CH), 127.5 (CH), 127.9 (C), 128.5 (2×CH), 129.0 (2×CH), 129.4 (C), 139.7 (C), 139.78 (C), 141.6 (C), 143.5 (C), 158.58 (C), 172.4 (CO), 175.4 (CO). B: 13C NMR (150 MHz, DMSO-d6) δ = 40.7 (CH2), 42.4 (CH2), 54.8 (CH), 55.0 (CH3O), 58.41 (C), 109.4 (CH), 113.99 (2×CH), 122.7 (CH), 122.8 (CH), 126.7 (2×CH), 126.9 (2×CH), 126.69 (CH), 127.00 (2×CH), 127.5 (CH), 127.8 (C), 128.5 (2×CH), 129.0 (2×CH), 130.6 (C), 139.7 (C), 139.81 (C), 141.8 (C), 142.9 (C), 158.55 (C), 172.5 (CO), 175.2 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C31H27N2O3+ 475.2016; Found 475.2015. ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1-(4-Methoxybenzyl)-5'-(naphthalen-1-yl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2h) was obtained from 1h (86 mg, 0.21 mmol). Reaction time 4+4+8 h. Yield 32 mg (34%); orange viscous oil; dr 52:48; Rf = 0.47 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.45 (dd, 2J = 13.5, 3J = 6.8 Hz, 1H, CH2, A), 2.91 (dd, 2J = 13.5, 3J = 7.8 Hz, 1H, CH2, B), 3.12 (dd, 2J = 13.5, 3J = 7.8 Hz, 1H, CH2, B), 3.51 (dd, 2J = 13.5, 3J = 8.0 Hz, 1H, CH2, A), 3.70 (s, 3H, CH3O), 3.73 (s, 3H, CH3O), 4.82 (d, 2J = 15.5 Hz, 1H+1H, CH2, A. B), 4.93 (d, 2J = 15.5 Hz, 1H, CH2), 4.98 (d, 2J = 15.5 Hz, 1H, CH2), 5.93 (dd, 3J = 7.8, 3J = 7.8 Hz, 1H, CH, B), 6.06 (dd, 3J = 8.0, 3J = 6.8 Hz, 1H, CH, A), 6.71 (d, 3J = 7.8 Hz, 1H, Ar), 6.75–6.78 (m, 3H, Ar), 6.80–6.81 (m, 2H, Ar), 6.94–6.97 (m, 1H, Ar), 6.96 (br.s, 1H, NH), 6.99 (br.s, 1H, NH), 7.01–7.02 (m, 1H, Ar), 7.12–7.17 (m, 2H, Ar), 7.23–7.25 (m, 5H, Ar), 7.48–7.49 (m, 1H, Ar), 7.52–7.60 (m, 6H, Ar), 7.73 (br.d, 3J = 7.1 Hz, 1H, Ar), 7.82 (br.d, 3J = 7.1 Hz, 1H, Ar), 7.85 (br.d, 3J = 8.2 Hz, 1H, Ar), 7.87 (br.d, 3J = 8.1 Hz, 1H, Ar), 7.92–7.94 (m, 2H, Ar), 8.05– 8.08 (m, 2H, Ar).

13

C NMR (150 MHz, CDCl3) δ = 40.5 (CH2), 40.7 (CH2), 43.5 (CH2), 43.6

(CH2), 52.2 (CH), 52.9 (CH), 55.15 (CH3O), 55.17 (CH3O), 58.38 (C), 58.41 (C), 109.6 (CH), 109.8 (CH), 114.1 (2×CH), 114.2 (2×CH), 121.4 (CH), 122.2 (CH), 122.55 (CH), 122.61 (CH), 122.7 (CH), 123.06 (CH), 123.10 (CH), 123.4 (CH), 125.6 (CH), 125.85 (CH), 125.87 (CH), 126.1 (CH), 126.5 (CH), 126.7 (CH), 127.2 (C), 127.3 (C), 128.39 (2×CH), 128.43 (2×CH), 128.6 (2×CH), 128.98 (CH), 129.04 (C), 129.06 (CH), 129.07 (CH), 129.2 (CH), 130.11 (C), 130.14 (C), 130.2 (C), 134.0 (C), 133.9 (C), 136.7 (C), 138.0 (C), 143.4 (C), 143.7 (C), 158.97 (C), 159.01 (C), 173.6 (CO), 173.7 (CO), 174.9 (CO), 175.8 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C29H25N2O3+ 449.1860; Found 449.1862. 5'-(1,3-Benzodioxol-5-yl)-1-(4-methoxybenzyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)dione (2i) was obtained from 1i (92 mg, 0.23 mmol). Reaction time 2+4 h. Purification was performed on neutralized silica gel. Yield 55 mg (54%); yellowish solid, mp 237–239 °C; dr 56:44; Rf = 0.49 (A), 0.55 (B) (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3)

δ = 2.35 (dd, 2J = 13.3, 3J = 8.3 Hz, 1H, CH2, A), 2.75 (dd, 2J = 13.4, 3J = 7.4 Hz, 1H, CH2, B), 2.82 (dd, 2J = 13.4, 3J = 8.1 Hz, 1H, CH2, B), 3.04 (dd, 2J = 13.3, 3J = 7.0 Hz, 1H, CH2, A), 3.75 (s, 3H, CH3O, B), 3.76 (s, 3H, CH3O, A), 4.81 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.82 (d, 2J = 15.7 Hz, 1H, CH2, B), 4.91 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.97 (d, 2J = 15.7 Hz, 1H, CH2, B), 5.00 (dd, 3J = 8.1, 3J = 7.4 Hz, 1H, CH, B), 5.23 (dd, 3J = 8.3, 3J = 7.0 Hz, 1H, CH, A), 5.95 (d, 2J = 1.3 Hz, 1H, OCH2O, B), 5.96 (d, 2J = 1.3 Hz, 1H, OCH2O, B), 5.97 (d, 2J = 1.3 Hz, 1H, OCH2O, A), 5.98 (d, 2J = 1.3 Hz, 1H, OCH2O, A), 6.73–6.75 (m, 1H+1H, Ar, A, B), 6.78–6.84 (m, 4H+3H, Ar, NH, A, B), 6.88–6.93 (m, 1H+3H, Ar, A, B), 7.04–7.07 (m, 2H+1H, Ar, A, B), 7.18–7.22 (m, 2H+1H, Ar, A, B), 7.23–7.25 (m, 2H, Ar, A), 7.26–7.28 (m, 2H, Ar, B), 7.32–7.33 ACS Paragon Plus Environment

Page 28 of 42

Page 29 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

(m, 1H, Ar, B). A:

13

C NMR (150 MHz, CDCl3) δ = 42.2 (CH2), 43.4 (CH2), 55.17 (CH3O),

55.23 (CH), 58.6 (C), 101.3 (OCH2O), 106.1 (CH), 108.5 (CH), 109.5 (CH), 114.22 (2×CH), 119.4 (CH), 123.2 (CH), 123.3 (CH), 127.29(C), 128.38 (2×CH), 128.7 (C), 129.0 (CH), 135.3 (C), 143.8 (C), 147.6 (C), 148.32 (C), 159.03 (C), 173.3 (CO), 175.5 (CO). B:

13

C NMR (150

MHz, CDCl3) δ = 41.4 (CH2), 43.6 (CH2), 55.16 (CH3O), 56.2 (CH), 58.4 (C), 101.2 (OCH2O), 106.7 (CH), 108.3 (CH), 109.7 (CH), 114.16 (2×CH), 119.9 (CH), 122.4 (CH), 122.9 (CH), 127.31 (C), 128.43 (2×CH), 128.9 (CH), 130.2 (C), 135.1 (C), 143.2 (C), 147.7 (C), 148.28 (C), 159.00 (C), 173.4 (CO), 175.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C26H23N2O5+ 443.1601; Found 443.1603. 1-(4-Methoxybenzyl)-5'-(3,4,5-trimethoxyphenyl)-2'H-spiro[indole-3,3'-pyrrolidine]2,2'(1H)-dione (2j) was obtained from 1j (210 mg, 0.47 mmol). Reaction time 2+4 h. Purification was performed on neutralized silica gel. Yield 145 mg (63%); yellow solid, mp 166– 168 °C; dr 54:46; Rf = 0.21 (A), 0.25 (B) (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, DMSO-d6) δ = 2.29 (dd, 2J = 13.1, 3J = 8.1 Hz, 1H, CH2, A), 2.47 (dd, 2J = 13.2, 3J = 8.1 Hz, 1H, CH2, B), 2.80 (dd, 2J = 13.2, 3J = 7.4 Hz, 1H, CH2, B), 2.99 (dd, 2J = 13.1, 3J = 7.0 Hz, 1H, CH2, A), 3.669 (s, 3H, CH3O, A), 3.673 (s, 3H, CH3O, B), 3.709 (s, 3H, CH3O, B), 3.713 (s, 3H, CH3O, A), 3.82 (s, 6H, CH3O, B), 3.84 (s, 6H, CH3O, A), 4.78 (d, 2J = 15.7 Hz, 1H, CH2, B), 4.81 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.88 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.94 (d, 2J = 15.7 Hz, 1H, CH2, B), 5.09 (dd, 3J = 8.1, 3J = 7.0 Hz, 1H, CH, A), 5.15 (dd, 3J = 8.1, 3J = 7.4 Hz, 1H, CH, B), 6.81 (s, 2H, Ar, A), 6.83 (s, 2H, Ar, B), 6.87–6.90 (m, 2H+2H, Ar, A, B), 6.92–6.93 (m, 1H+1H, Ar, A, B), 7.02–7.04 (m, 1H, Ar, A), 7.06–7.09 (m, 1H, Ar, B), 7.22–7.24 (m, 1H, Ar, A), 7.24–7.27 (m, 1H, Ar, B), 7.28–7.31 (m, 3H+2H, Ar, A, B), 7.48–7.49 (m, 1H, Ar, B), 8.87 (br.s, 1H, NH, B), 8.88 (br.s, 1H, NH, A). A: 13C NMR (150 MHz, DMSO-d6) δ = 41.1 (CH2), 42.1 (CH2), 54.9 (CH), 55.0 (CH3O), 56.0 (2×CH3O), 58.4 (C), 60.00 (CH3O), 103.3 (2×CH), 109.2 (CH), 114.02 (2×CH), 122.60 (CH), 123.6 (CH), 127.9 (CH), 128.52 (2×CH), 128.6 (C), 129.2 (C), 136.9 (C), 137.9 (C), 143.5 (C), 153.11 (2×C), 158.57 (C), 172.4 (CO), 175.4 (CO). B: 13C NMR (150 MHz, DMSO-d6) δ = 40.6 (CH2), 42.4 (CH2), 55.0 (CH3O), 55.2 (CH), 55.9 (2×CH3O), 58.3 (C), 60.02 (CH3O), 103.4 (2×CH), 109.4 (CH), 113.97 (2×CH), 122.62 (CH), 122.8 (CH), 127.8 (CH), 128.50 (2×CH), 128.53 (C), 130.6 (C), 136.9 (C), 138.3 (C), 142.9 (C), 153.05 (2×C), 158.55 (C), 172.4 (CO), 175.2 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C28H29N2O6+ 489.2020; Found 489.2027. 1-(4-Methoxybenzyl)-5'-(thien-2-yl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2k) was obtained from 1k (77 mg, 0.21 mmol). Purification was performed on neutralized silica gel. ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Reaction time 2+1 h. Yield 48 mg (56%); orange solid, mp 194–196 °C; dr 52:48; Rf = 0.42 (A), 0.38 (B) (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.55 (dd, 2J = 13.4, 3J = 7.8 Hz, 1H, CH2, A), 2.84 (ddd, 2J = 13.3, 3J = 7.3, 5J = 0.7 Hz, 1H, CH2, B), 3.00 (dd, 2

J = 13.3, 3J = 8.2 Hz, 1H, CH2, B), 3.15 (ddd, 2J = 13.4, 3J = 7.2, 5J = 0.6 Hz, 1H, CH2, A), 3.76

(s, 3H, CH3O, B), 3.77 (s, 3H, CH3O, A), 4.81 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.83 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.92 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.98 (d, 2J = 15.6 Hz, 1H, CH2, B), 5.39 (dd, 3J = 8.2, 3J = 7.3 Hz, 1H, CH, B), 5.59 (dd, 3J = 7.8, 3J = 7.2 Hz, 1H, CH, A), 6.74–6.76 (m, 1H+1H, Ar, A, B), 6.82–6.86 (m, 2H+2H, Ar, A, B), 6.87 (br.s, 1H, NH, A), 6.94 (br.s, 1H, NH, B), 7.00–7.02 (m, 1H+1H, Ar, A, B), 7.05–7.08 (m, 1H+1H, Ar, A, B), 7.11–7.12 (m, 1H, Ar, A), 7.19–7.23 (m, 1H+1H, Ar, A, B), 7.24–7.26 (m, 2H, Ar, A), 7.28–7.29 (m, 2H, Ar, B), 7.30– 7.33 (m, 1H+2H, Ar, A, B). A: 13C NMR (150 MHz, CDCl3) δ = 42.3 (CH2), 43.4 (CH2), 51.5 (CH), 55.20 (CH3O), 58.43 (C), 109.6 (CH), 114.22 (2×CH), 123.2 (CH), 123.4 (CH), 125.0 (CH), 125.3 (CH), 127.12 (CH), 127.2 (C), 128.4 (2×CH), 128.5 (C), 129.1 (CH), 143.7 (C), 145.4 (C), 159.02 (C), 172.6 (CO), 175.4 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 41.6 (CH2), 43.6 (CH2), 52.1 (CH), 55.18 (CH3O), 58.40 (C), 109.8 (CH), 114.16 (2×CH), 122.5 (CH), 123.0 (CH), 125.2 (CH), 125.5 (CH), 127.09 (CH), 127.3 (C), 128.5 (2×CH), 129.0 (CH), 129.8 (C), 143.2 (C), 144.5 (C), 158.98 (C), 172.8 (CO), 174.7 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C23H21N2O3S+ 405.1267; Found 405.1271. 5-Methyl-1-(4-methoxybenzyl)-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2l) was obtained from 1l (369 mg, 1.0 mmol). Reaction time 7+3 h. Yield 260 mg (63%); white foam; dr 52:48; Rf = 0.24 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.29 (s, 3H, CH3, A), 2.34 (s, 3H, CH3, B), 2.40 (dd, 2J = 13.3, 3J = 8.5 Hz, 1H, CH2, A), 2.80 (dd, 2J = 13.4, 3J = 7.5 Hz, 1H, CH2, B), 2.88 (dd, 2J = 13.4, 3J = 8.3 Hz, 1H, CH2, B), 3.08 (dd, 2

J = 13.3, 3J = 7.0 Hz, 1H, CH2, A), 3.76 (s, 3H, CH3O, B), 3.77 (s, 3H, CH3O, A), 4.81 (d, 2J =

15.6 Hz, 1H, CH2, A), 4.83 (d, 2J = 15.6 Hz, 1H, CH2, B), 4.90 (d, 2J = 15.6 Hz, 1H, CH2, A), 4.96 (d, 2J = 15.6 Hz, 1H, CH2, B), 5.10 (dd, 3J = 8.3, 3J = 7.56.9 Hz, 1H, CH, B), 5.35 (dd, 3J = 8.5, 3J = 7.0 Hz, 1H, CH, A), 6.52 (br.s, 1H, NH, A), 6.55 (br.s, 1H, NH, B), 6.63–6.64 (m, 1H+1H, Ar, A, B), 6.81–6.85 (m, 2H+2H, Ar, A, B), 7.00–7.02 (m, 2H+2H, Ar, A, B), 7.17– 7.18 (m, 1H, Ar, B), 7.21–7.28 (m, 2H+2H, Ar, A, B), 7.35–7.47 (m, 4H+3H, Ar, A, B), 7.53– 7.54 (m, 1H+1H, Ar, A, B).

13

C NMR (150 MHz, CDCl3) δ = 21.1 (2×CH3), 41.4 (CH2), 42.3

(CH2), 43.4 (CH2), 43.6 (CH2), 55.2 (2×CH3O), 55.4 (CH), 56.4 (CH), 58.4 (C), 58.6 (C), 109.3 (CH), 109.5 (CH), 114.15 (2×CH), 114.21 (2×CH), 123.3 (CH), 124.1 (CH), 125.9 (2×CH), 126.4 (2×CH), 127.4 (2×C), 128.3 (CH), 128.4 (2×CH), 128.46 (3×CH), 128.49 (C), 129.0 (2×CH), 129.1 (2×CH), 129.2 (CH), 129.4 (CH), 130.2 (C), 132.6 (C), 132.8 (C), 140.8 (C), ACS Paragon Plus Environment

Page 30 of 42

Page 31 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

141.2 (C), 141.4 (C), 141.5 (C), 158.96 (C), 159.01 (C), 173.5 (CO), 173.6 (CO), 175.0 (CO), 175.4 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C26H25N2O3+ 413.1860; Found 413.1873. 5-Fluoro-1-(4-methoxybenzyl)-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2m) was obtained from 1m (373 mg, 1.0 mmol). Reaction time 2 h. Yield 266 mg (64%); yellowish foam; dr 51:49; Rf = 0.18 (petroleum ether – ethyl acetate, 2:1). 1H NMR (600 MHz, CDCl3) δ = 2.35 (dd, 2J = 13.4, 3J = 8.0 Hz, 1H, CH2, A), 2.79 (dd, 2J = 13.5, 3J = 7.5 Hz, 1H, CH2, B), 2.86 (dd, 2J = 13.5, 3J = 8.2 Hz, 1H, CH2, B), 3.13 (dd, 2J = 13.4, 3J = 7.2 Hz, 1H, CH2, A), 3.74 (s, 3H, CH3O), 3.76 (s, 3H, CH3O), 4.78 (d, 2J = 15.7 Hz, 1H, CH2), 4.79 (d, 2J = 15.7 Hz, 1H, CH2), 4.91 (d, 2J = 15.7 Hz, 1H, CH2), 4.96 (d, 2J = 15.7 Hz, 1H, CH2), 5.06 (dd, 3J = 8.2, 3J = 7.5 Hz, 1H, CH, B), 5.31 (dd, 3J = 8.0, 3J = 7.2 Hz, 1H, CH, A), 6.63–6.66 (m, 2H, Ar), 6.79–6.84 (m, 4H, Ar), 6.86–6.92 (m, 3H, Ar), 7.11–7.13 (m, 1H, Ar), 7.21–7.26 (m, 4H, Ar), 7.24 (br.s, 1H, NH), 7.28 (br.s, 1H, NH), 7.32–7.37 (m, 2H, Ar), 7.39–7.44 (m, 6H, Ar), 7.49– 7.51 (m, 2H, Ar). 13C NMR (150 MHz, CDCl3) δ = 41.0 (1JCH = 133 Hz, CH2), 41.9 (1JCH = 133 Hz, CH2), 43.5 (1JCH = 139 Hz, CH2), 43.6 (1JCH = 139 Hz, CH2), 55.13 (1JCH = 144 Hz, CH3O), 55.14 (1JCH = 144 Hz, CH3O), 55.3 (1JCH = 145 Hz, CH), 56.3 (1JCH = 145 Hz, CH), 58.8 (C), 58.9 (C), 110.1 (3JCF = 8 Hz, CH), 110.2 (3JCF = 8 Hz, CH), 110.8 (2JCF = 25 Hz, CH), 111.5 (2JCF = 25 Hz, CH), 114.16 (2×CH), 114.22 (2×CH), 115.1 (2JCF = 25 Hz, CH), 115.3 (2JCF = 25 Hz, CH), 125.7 (2×CH), 126.3 (2×CH), 126.9 (CH), 128.2 (CH), 128.3 (2×CH), 128.4 (2×CH), 129.0 (2×CH), 129.1 (2×CH), 130.1 (3JCF = 8 Hz, C), 131.4 (3JCF = 8 Hz, C), 139.1 (C), 139.6 (C), 141.0 (C), 141.3 (C), 158.99 (C), 159.03 (C), 159.2 (1JCF = 242 Hz, C), 159.3 (1JCF = 242 Hz, C), 173.0 (CO), 173.1 (CO), 174.8 (CO), 175.2 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H22FN2O3+ 417.1609; Found 417.1611. Ethyl 4-[5-fluoro-1-(4-methoxybenzyl)-2,2'-dioxo-1,2-dihydrospiro[indole-3,3'-pyrrolidine]5'-yl]benzoate (2n) was obtained from 1n (356 mg, 0.80 mmol). Reaction time 2 h. Yield 165 mg (42%); brown foam; dr 51:49; Rf = 0.47 (A), 0.38 (B) (petroleum ether – ethyl acetate, 1:1). 1

H NMR (600 MHz, CDCl3) δ = 1.38 (t, 3J = 7.1 Hz, 3H, CH3), 1.40 (t, 3J = 7.1 Hz, 3H, CH3),

2.30 (dd, 2J = 13.4, 3J = 8.0 Hz, 1H, CH2, A), 2.78 (dd, 2J = 13.6, 3J = 7.8 Hz, 1H, CH2, B), 2.83 (dd, 2J = 13.6, 3J = 7.8 Hz, 1H, CH2, B), 3.14 (dd, 2J = 13.4, 3J = 7.3 Hz, 1H, CH2, A), 3.71 (s, 3H, CH3O), 3.73 (s, 3H, CH3O), 4.36 (q, 3J = 7.1 Hz, 2H, CH2O), 4.38 (q, 3J = 7.1 Hz, 2H, CH2O), 4.75 (d, 2J = 15.7 Hz, 1H, CH2), 4.76 (d, 2J = 15.7 Hz, 1H, CH2), 4.88 (d, 2J = 15.7 Hz, 1H, CH2), 4.93 (d, 2J = 15.7 Hz, 1H, CH2), 5.10–5.13 (m, 1H, CH), 5.34–5.37 (m, 1H, CH), 6.61–6.65 (m, 2H, Ar), 6.75–6.79 (m, 4H, Ar), 6.85–6.91 (m, 3H, Ar), 7.09–7.11 (m, 1H, Ar), 7.17–7.22 (m, 4H, Ar), 7.46–7.47 (m, 2H, Ar), 7.53–7.54 (m, 2H, Ar), 7.66–7.71 (m, 1H, NH), 7.71–7.75 (m, 1H, NH), 8.04–8.07 (m, 4H, Ar). 13C NMR (150 MHz, CDCl3) δ = 14.2 (2×CH3), ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

40.6 (CH2), 41.5 (CH2), 43.4 (CH2), 43.6 (CH2), 55.07 (CH3O), 55.09 (CH3O), 55.13 (CH), 55.9 (CH), 58.7 (C), 58.8 (C), 60.95 (CH2O), 61.01 (CH2O), 110.2 (3JCF = 9 Hz, CH), 110.3 (3JCF = 9 Hz, CH), 110.8 (2JCF = 25 Hz, CH), 111.4 (2JCF = 25 Hz, CH), 114.1 (2×CH), 114.2 (2×CH), 115.1 (2JCF = 24 Hz, CH), 115.4 (2JCF = 24 Hz, CH), 125.5 (2×CH), 126.1 (2×CH), 126.7 (C), 126.8 (C), 128.2 (2×CH), 128.3 (2×CH), 129.9 (3JCF = 8 Hz, C), 130.2 (2×CH), 130.3 (2×CH), 130.4 (3JCF = 8 Hz, 2×C), 131.1 (3JCF = 8 Hz, C), 139.1 (C), 139.5 (C), 146.0 (C), 146.3 (C), 158.98 (C), 159.02 (C), 159.2 (1JCF = 242 Hz, C), 159.3 (1JCF = 242 Hz, C), 165.96 (CO2Et), 166.01 (CO2Et), 173.3 (CO), 173.4 (CO), 174.7 (CO), 175.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C28H26FN2O5+ 489.1820; Found 489.1828. 5-Chloro-1-(4-methoxybenzyl)-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2o) was obtained from 1o (389 mg, 1.0 mmol). Reaction time 100 min. Yield 217 mg (50%); white solid, mp 208–210 °C; dr 52:48; Rf = 0.56 (A), 0.43 (B) (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, DMSO-d6) δ = 2.36 (dd, 2J = 13.2, 3J = 8.1 Hz, 1H, CH2, A), 2.45 (dd, 2

J = 13.3, 3J = 8.2 Hz, 1H, CH2, B), 2.85 (dd, 2J = 13.3, 3J = 7.4 Hz, 1H, CH2, B), 3.00 (dd, 2J =

13.2, 3J = 6.9 Hz, 1H, CH2, A), 3.710 (s, 3H, CH3O, B), 3.713 (s, 3H, CH3O, A), 4.77 (d, 2J = 15.7 Hz, 1H, CH2, B), 4.80 (d, 2J = 15.7 Hz, 1H, CH2, A), 4.91 (d, 2J = 15.7 Hz, 1H, CH2, A), 4.96 (d, 2J = 15.7 Hz, 1H, CH2, B), 5.13 (dd, 3J = 8.1, 3J = 6.9 Hz, 1H, CH, A), 5.29 (dd, 3J = 8.2, 3J = 7.4 Hz, 1H, CH, B), 6.87–6.90 (m, 2H+2H, Ar, A, B), 6.91–6.94 (m, 1H+1H, Ar, A, B), 7.26–7.28 (m, 2H, Ar, A), 7.29–7.31 (m, 1H+2H, Ar, A, B), 7.32–7.37 (m, 1H+2H, Ar, A, B), 7.40–7.41 (m, 1H, Ar, A), 7.43–7.45 (m, 2H+2H, Ar, A, B), 7.49–7.50 (m, 2H, Ar, B), 7.56–7.57 (m, 2H, Ar, A), 7.66–7.67 (m, 1H, Ar, B), 8.94 (br.s, 1H, NH, B), 8.97 (br.s, 1H, NH, A). A: 13C NMR (150 MHz, DMSO-d6) δ = 40.9 (CH2), 42.2 (CH2), 54.84 (CH), 55.0 (CH3O), 58.7 (C), 110.6 (CH), 114.1 (2×CH), 124.0 (CH), 126.6 (2×CH), 126.9 (CH), 127.53 (C), 127.84 (C), 128.4 (CH), 128.5 (2×CH), 128.6 (2×CH), 131.1 (C), 142.0 (C), 142.4 (C), 158.62 (C), 171.7 (CO), 175.04 (CO). B: 13C NMR (150 MHz, DMSO-d6) δ = 40.3 (CH2), 42.5 (CH2), 54.81 (CH), 55.0 (CH3O), 58.7 (C), 110.7 (CH), 114.0 (2×CH), 123.1 (CH), 126.3 (2×CH), 126.8 (CH), 127.46 (C), 127.76 (C), 128.3 (CH), 128.5 (2×CH), 128.7 (2×CH), 132.4 (C), 141.9 (C), 142.0 (C), 158.59 (C), 171.8 (CO), 174.97 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H22ClN2O3+ 433.1313; Found 433.1323. 5-Bromo-1-(4-methoxybenzyl)-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2p) was obtained from 1p (433 mg, 1.0 mmol). Reaction time 100 min. Yield 300 mg (63%); white solid, mp 228–230 °C; dr 52:48; Rf = 0.56 (A), 0.47 (B) (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, DMSO-d6) δ = 2.36 (dd, 2J = 13.2, 3J = 8.2 Hz, 1H, CH2, A), 2.43 (dd, ACS Paragon Plus Environment

Page 32 of 42

Page 33 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

2

J = 13.3, 3J = 8.2 Hz, 1H, CH2, B), 2.85 (dd, 2J = 13.3, 3J = 7.5 Hz, 1H, CH2, B), 3.00 (dd, 2J =

13.2, 3J = 7.0 Hz, 1H, CH2, A), 3.710 (s, 3H, CH3O, B), 3.711 (s, 3H, CH3O, A), 4.76 (d, 2J = 15.8 Hz, 1H, CH2, B), 4.79 (d, 2J = 15.7 Hz, 1H, CH2, A), 4.90 (d, 2J = 15.7 Hz, 1H, CH2, A), 4.95 (d, 2J = 15.8 Hz, 1H, CH2, B), 5.12 (dd, 3J = 8.2, 3J = 7.0 Hz, 1H, CH, A), 5.28 (dd, 3J = 8.2, 3J = 7.5 Hz, 1H, CH, B), 6.87–6.90 (m, 3H+3H, Ar, A, B), 7.25–7.27 (m, 2H, Ar, A), 7.28– 7.30 (m, 2H, Ar, B), 7.34–7.37 (m, 1H+1H, Ar, A, B), 7.42–7.46 (m, 3H+3H, Ar, A, B), 7.48– 7.49 (m, 2H, Ar, B), 7.51–7.52 (m, 1H, Ar, A), 7.56–7.57 (m, 2H, Ar, A), 7.76–7.77 (m, 1H, Ar, B), 8.94 (br.s, 1H, NH, B), 8.97 (br.s, 1H, NH, A).

13

C NMR (150 MHz, DMSO-d6) δ = 40.3

(CH2), 40.8 (CH2), 42.2 (CH2), 42.4 (CH2), 54.79 (CH), 54.84 (CH), 55.0 (2×CH3O), 58.6 (2×C), 111.1 (CH), 111.3 (CH), 114.0 (2×CH), 114.1 (2×CH), 114.54 (C), 114.56 (C), 125.7 (CH), 126.3 (2×CH), 126.6 (2×CH), 126.7 (CH), 127.4 (C), 127.5 (C), 127.75 (CH), 127.83 (CH), 128.5 (4×CH), 128.6 (2×CH), 128.7 (2×CH), 131.2 (CH), 131.3 (CH), 131.4 (C), 132.8 (C), 142.0 (C), 142.3 (C), 142.6 (C), 142.9 (C), 158.59 (C), 158.61 (C), 171.7 (CO), 171.8 (CO), 174.94 (CO), 174.88 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C25H22BrN2O3+ 477.0808; Found 477.0829. 1-Methyl-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione17 (2q) was obtained from 1q (397 mg, 1.59 mmol). Reaction time 2+6 h. Yield 280 mg (67%, based on 90% conversion); yellow solid, mp 195–196 °C (lit. 198–200 °C); dr 50:50; Rf = 0.6 (ethyl acetate). A: 1H NMR (600 MHz, CDCl3) δ = 2.33 (dd, 2J = 13.5, 3J = 8.0 Hz, 1H, CH2), 3.01 (dd, 2J = 13.5, 3J = 7.4 Hz, 1H, CH2), 3.20 (s, 3H, CH3N), 5.22 (dd, 3J = 8.0, 3J = 7.4 Hz, 1H, CH), 6.84 (d, 3J = 7.8 Hz, 1H, Ar), 7.04–7.06 (m, 1H, Ar), 7.12 (d, 3J = 7.9 Hz, 1H, Ar), 7.28–7.33 (m, 3H, Ar), 7.37–7.40 (m, 3H+1H, Ar, NH). 13C NMR (150 MHz, CDCl3) δ = 26.4 (CH3N), 41.8 (CH2), 55.3 (CH), 58.6 (C), 108.6 (CH), 123.16 (CH), 123.22 (CH), 125.7 (2×CH), 128.2 (CH), 128.5 (C), 129.0 (2×CH), 129.2 (CH), 141.4 (C), 144.5 (C), 173.7 (CO), 175.6 (CO). 1-Methyl-5'-(4-tolyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2r) was obtained from 1r (400 mg, 1.52 mmol). Reaction time 2+7 h. Yield 255 mg (61%, based on 90% conversion); white solid, mp 234–235 °C; dr 50:50; Rf = 0.67 (ethyl acetate). 1H NMR (600 MHz, CDCl3) δ = 2.36 (dd, 2J = 13.5, 3J = 8.3 Hz, 1H, CH2, A), 2.37 (CH3), 2.38 (CH3), 2.72 (dd, 2J = 13.4, 3J = 7.2 Hz, 1H, CH2, B), 2.79 (dd, 2J = 13.4, 3J = 8.4 Hz, 1H, CH2, B), 3.02 (dd, 2

J = 13.5, 3J = 7.1 Hz, 1H, CH2, A), 3.23 (s, 3H, CH3N, A), 3.26 (s, 3H, CH3N, B), 5.04 (dd, 3J =

8.4, 3J = 7.2 Hz, 1H, CH, B), 5.26 (dd, 3J = 8.3, 3J = 7.1 Hz, 1H, CH, A), 6.43 (br.s, 1H, NH, A), 6.49 (br.s, 1H, NH, B), 6.86–6.89 (m, 1H+1H, Ar, A, B), 7.08–7.13 (m, 1H+1H, Ar, A, B), 7.18–7.24 (m, 3H+2H, Ar, A, B), 7.30–7.36 (m, 3H+2H, Ar, A, B), 7.38–7.39 (m, 2H, Ar, B). ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 34 of 42

A: 13C NMR (150 MHz, CDCl3) δ = 21.1 (CH3), 26.5 (CH3N), 42.3 (CH2), 55.1 (CH), 58.5 (C), 108.5 (CH), 123.2 (CH), 123.3 (CH), 125.8 (2×CH), 128.6 (C), 129.2 (CH), 129.74 (2×CH), 138.2 (C), 138.5 (C), 144.7 (C), 173.2 (CO), 175.4 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 21.1 (CH3), 26.7 (CH3N), 41.8 (CH2), 56.1 (CH), 58.4 (C), 108.7 (CH), 122.4 (CH), 123.0 (CH), 126.4 (2×CH), 129.1 (CH), 129.65 (2×CH), 130.1 (C), 138.0 (C), 138.3 (C), 144.2 (C), 173.4 (CO), 174.8 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C19H19N2O2+ 307.1441; Found 307.1438. 5'-(4-Methoxyphenyl)-1-methyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2s) was obtained from 1s (120 mg, 0.43 mmol). Reaction time 2+4 h. Purification was performed on neutralized silica gel. Yield 89 mg (64%); white solid, mp 231–232 °C; dr 54:46; Rf = 0.11 (petroleum ether – ethyl acetate, 1:1). 1H NMR (600 MHz, CDCl3) δ = 2.31 (dd, 2J = 13.3, 3J = 8.1 Hz, 1H, CH2, A), 2.68 (dd, 2J = 13.3, 3J = 7.4 Hz, 1H, CH2, B), 2.73 (dd, 2J = 13.3, 3J = 8.3 Hz, 1H, CH2, B), 2.99 (dd, 2J = 13.3, 3J = 7.1 Hz, 1H, CH2, A), 3.20 (s, 3H, CH3N, A), 3.23 (s, 3H, CH3N, B), 3.79 (s, 3H, CH3O, B), 3.81 (s, 3H, CH3O, A), 5.00 (dd, 3J = 8.1, 3J = 7.1 Hz, 1H, CH, A), 5.20 (dd, 3J = 8.3, 3J = 7.4 Hz, 1H, CH, B), 6.84–6.93 (m, 3H+3H, Ar, NH, A, B), 6.96 (br.s, 1H, NH, B), 7.07–7.12 (m, 2H+1H, Ar, A, B), 7.16–7.17 (m, 1H, Ar, B), 7.30–7.35 (m, 2H+3H, Ar, A, B), 7.37–7.39 (m, 2H, Ar, A). A: 13C NMR (150 MHz, CDCl3) δ = 26.5 (CH3N), 42.2 (CH2), 54.8 (CH), 55.3 (CH3O), 58.52 (C), 108.5 (CH), 114.3 (2×CH), 123.1 (CH), 123.2 (CH), 127.0 (2×CH), 128.7 (C), 129.05 (CH), 133.4 (C), 144.5 (C), 159.4 (C), 173.4 (CO), 175.4 (CO). B: 13C NMR (150 MHz, CDCl3) δ = 26.6 (CH3N), 41.7 (CH2), 55.2 (CH3O), 55.9 (CH), 58.46 (C), 108.6 (CH), 114.2 (2×CH), 122.4 (CH), 122.9 (CH), 127.6 (2×CH), 128.95 (CH), 130.1 (C), 133.0 (C), 144.0 (C), 159.5 (C), 173.5 (CO), 174.9 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C19H19N2O3+ 323.1390; Found 323.1391. 5'-(1,3-Benzodioxol-5-yl)-1-methyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione

(2t)

was obtained from 1t (86 mg, 0.29 mmol). Reaction time 2+5 h. Purification was performed on neutralized silica gel. Yield 53 mg (54%); brown solid, mp 243–244 °C; dr 51:49; Rf = 0.67 (ethyl acetate). 1H NMR (600 MHz, CDCl3) δ = 2.32 (dd, 2J = 13.4, 3J = 8.3 Hz, 1H, CH2, A), 2.71 (ddd, 2J = 13.5, 3J = 7.5, 5J = 0.7 Hz, 1H, CH2, B), 2.75 (dd, 2J = 13.5, 3J = 8.1 Hz, 1H, CH2, B), 2.98 (ddd, 2J = 13.4, 3J = 7.1, 5J = 0.8 Hz, 1H, CH2, A), 3.23 (s, 3H, CH3N, A), 3.26 (s, 3H, CH3N, B), 4.98 (dd, 3J = 8.1, 3J = 7.5 Hz, 1H, CH, B), 5.20 (dd, 3J = 8.3, 3J = 7.1 Hz, 1H, CH, A), 5.98 (br.s, 2H, OCH2O), 5.99 (br.s, 2H, OCH2O), 6.52 (br.s, 1H, NH, A), 6.57 (br.s, 1H, NH, B), 6.80 (d, 3J = 7.9 Hz, 1H, Ar, B), 6.83 (d, 3J = 7.8 Hz, 1H, Ar, A), 6.86–6.92 (m, 3H+2H, Ar, A, B), 7.04–7.05 (m, 1H, Ar, B), 7.09–7.12 (m, 1H+1H, Ar, A, B), 7.20–7.21 (m, 1H, Ar, ACS Paragon Plus Environment

Page 35 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

A), 7.32–7.35 (m, 1H+2H, Ar, A, B). A:

13

C NMR (150 MHz, CDCl3) δ = 26.6 (CH3N), 42.3

(CH2), 55.2 (CH), 58.5 (C), 101.30 (OCH2O), 106.1 (CH), 108.6 (2×CH), 119.4 (CH), 123.2 (CH), 123.3 (CH), 128.5 (C), 129.2 (CH), 135.3 (C), 144.7 (C), 147.6 (C), 148.4 (C), 173.2 (CO), 175.3 (CO). B:

13

C NMR (150 MHz, CDCl3) δ = 26.8 (CH3N), 41.7 (CH2), 56.2 (CH),

58.3 (C), 101.27 (OCH2O), 106.7 (CH), 108.4 (CH), 108.7 (CH), 120.0 (CH), 122.4 (CH), 123.0 (CH), 129.1 (CH), 130.1 (C), 134.9 (C), 144.2 (C), 147.7 (C), 148.3 (C), 173.3 (CO), 174.9 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C19H17N2O4+ 337.1183; Found 337.1184. 1-Methyl-5'-(3,4,5-trimethoxyphenyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (2u) was obtained from 1u (100 mg, 0.30 mmol). Reaction time 2+5 h. Purification was performed on neutralized silica gel. Yield 64 mg (57%); white solid, mp 222–223 °C; dr 51:49; Rf = 0.50 (A), 0.43 (B) (ethyl acetate). 1H NMR (600 MHz, DMSO-d6) δ = 2.24 (dd, 2J = 13.3, 3J = 8.1 Hz, 1H, CH2, A), 2.41 (dd, 2J = 13.3, 3J = 8.2 Hz, 1H, CH2, B), 2.73 (dd, 2J = 13.3, 3J = 7.4 Hz, 1H, CH2, B), 2.94 (dd, 2J = 13.3, 3J = 7.1 Hz, 1H, CH2, A), 3.15 (s, 3H, CH3N, A), 3.17 (s, 3H, CH3N, B), 3.67 (s, 3H+3H, CH3O, A, B), 3.82 (s, 3H+3H, CH3O, A, B), 3.83 (s, 3H+3H, CH3O, A, B), 5.04 (dd, 3J = 8.1, 3J = 7.1 Hz, 1H, CH, A), 5.13 (dd, 3J = 8.2, 3J = 7.4 Hz, 1H, CH, B), 6.79 (s, 2H, Ar), 6.82 (s, 2H, Ar), 7.03–7.04 (m, 1H, Ar, A), 7.05–7.08 (m, 1H+1H, Ar, A, B), 7.09–7.12 (m, 1H, Ar, B), 7.27–7.29 (m, 1H, Ar, A), 7.31–7.37 (m, 1H+H, Ar, A, B), 7.46–7.48 (m, 1H, Ar, B), 8.81 (br.s, 1H, NH, B), 8.83 (br.s, 1H, NH, A). A:

13

C NMR (150

MHz, DMSO-d6) δ = 26.2 (CH3N), 41.1 (CH2), 54.8 (CH), 56.0 (2×CH3O), 58.28 (C), 60.01 (CH3O), 103.3 (2×CH), 108.6 (CH), 122.55 (CH), 123.4 (CH), 128.71 (CH), 129.2 (C), 136.9 (C), 138.0 (C), 144.6 (C), 153.1 (2×C), 172.4 (CO), 175.2 (CO). B:

13

C NMR (150 MHz,

DMSO-d6) δ = 26.4 (CH3N), 40.7 (CH2), 55.2 (CH), 55.9 (2×CH3O), 58.27 (C), 60.02 (CH3O), 103.4 (2×CH), 108.7 (CH), 122.57 (CH), 122.59 (CH), 128.69 (CH), 130.5 (C), 136.9 (C), 138.3 (C), 144.0 (C), 153.0 (2×C), 172.4 (CO), 175.0 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C21H23N2O5+ 383.1601; Found 383.1609. General procedure20 for PMB-N-deprotection of 2. To solution of 2 (0.20 mmol, 1.0 equiv) in CH2Cl2 (2.50 mL, 0.08 M) TFA (0.75 mL, 10.0 mmol, 50 equiv) and TfOH (44 µL, 5.0 mmol, 2.5 equiv) were sequentially added. The resulting solution was stirred at room temperature for the time specified. Reaction mixture was then poured into ice–water mixture and extracted with EtOAc (3×20 mL). Combined organic layers were washed with NaHCO3 solution, dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by column chromatography on neutralized silica gel (ethyl acetate – petroleum ether).

ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 36 of 42

5'-Phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (3a) was obtained from 2a (89 mg, 0.224 mmol). Reaction time 54 h. Yield 33 mg (53%); white solid, mp 274–275 °C; dr 54:46; Rf = 0.72 (ethyl acetate). 1H NMR (600 MHz, DMSO-d6) δ = 2.18 (dd, 2J = 13.3, 3J = 7.9 Hz, 1H, CH2, A), 2.36 (dd, 2J = 13.2, 3J = 8.6 Hz, 1H, CH2, B), 2.71 (dd, 2J = 13.2, 3J = 7.3 Hz, 1H, CH2, B), 2.98 (dd, 2J = 13.3, 3J = 7.3 Hz, 1H, CH2, A), 5.03 (dd, 3J = 7.9, 3J = 7.3 Hz, 1H, CH2, A), 5.15 (dd, 3J = 8.6, 3J = 7.3 Hz, 1H, CH2, B), 6.84–6.86 (m, 1H, Ar, A), 6.87–6.90 (m, 1H, Ar, B), 6.94–6.98 (m, 1H, Ar, A), 7.00–7.04 (m, 1H, Ar, B), 7.12–7.15 (m, 1H, Ar, A), 7.19–7.23 (m, 1H, Ar, A), 7.23–7.27 (m, 1H, Ar, B), 7.32–7.37 (m, 1H+1H, Ar, A, B), 7.41–7.51 (m, 4H+5H, Ar, A, B), 8.77 (s, 1H, NH, B), 8.80 (s, 1H, NH, A), 10.56 (s, 1H, NH, A), 10.60 (s, 1H, NH, B). 13C NMR (150 MHz, DMSO-d6) δ = 40.9 (CH2), 41.2 (CH2), 54.6 (CH), 55.0 (CH), 58.7 (C), 58.8 (C), 109.4 (CH), 109.6 (CH), 121.9 (2×CH), 122.9 (CH), 123.5 (CH), 126.23 (2×CH), 126.24 (2×CH), 127.7 (2×CH), 128.55 (CH), 128.56 (CH), 128.6 (2×CH), 128.7 (2×CH), 130.2 (C), 131.4 (C), 142.5 (C), 142.66 (C), 142.71 (C), 143.1 (C), 172.6 (CO), 172.7 (CO), 176.6 (CO), 177.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C17H15N2O2+ 279.1128; Found 279.1133. 5'-(3,4,5-Trimethoxyphenyl)-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione

(3b)

was

obtained from 2j (105 mg, 0.215 mmol). Reaction time 114 h. Yield 40 mg (51%); yellow solid, mp 249–250 °C; dr 53:47; Rf = 0.45 (ethyl acetate). 1H NMR (600 MHz, DMSO-d6) δ = 2.21 (dd, 2J = 13.2, 3J = 8.2 Hz, 1H, CH2, A), 2.38 (dd, 2J = 13.2, 3J = 8.4 Hz, 1H, CH2, B), 2.71 (dd, 2

J = 13.2, 3J = 7.4 Hz, 1H, CH2, B), 2.94 (dd, 2J = 13.2, 3J = 7.2 Hz, 1H, CH2, A), 3.66 (s, 6H,

CH3O, B), 3.81 (s, 3H+3H, CH3O, A, B), 5.01 (dd, 3J = 8.2, 3J = 7.2 Hz, 1H, CH, A), 5.10 (dd, 3

J = 8.4, 3J = 7.4 Hz, 1H, CH, B), 6.78 (s, 1H, Ar, A), 6.80 (s, 1H, Ar, B), 6.83–6.87 (m, 1H, Ar,

A), 6.87–6.91 (m, 1H, Ar, B), 6.95–7.00 (m, 1H, Ar, A), 7.00–7.05 (m, Ar, 1H, Ar, B), 7.19– 7.27 (m, 2H+1H, Ar, A, B), 7.39–7.42 (m, 1H, Ar, B), 8.76 (br.s, 1H, NH, B), 8.78 (br.s, 1H, NH, A), 10.56 (br.s, 1H, NH), 10.60 (br.s, 1H, NH).

13

C NMR (150 MHz, DMSO-d6) δ = 40.7

(CH2), 41.1 (CH2), 54.8 (CH), 55.2 (CH), 55.9 (2×CH3O), 56.0 (2×CH3O), 58.7 (2×C), 60.0 (2×CH3O), 103.3 (2×CH), 103.4 (2×CH), 109.4 (CH), 109.6 (CH), 121.9 (2×CH), 122.9 (CH), 123.7 (CH), 128.6 (2×CH), 130.1 (C), 131.3 (C), 136.9 (2×C), 138.1 (C), 138.3 (C), 142.5 (C), 143.1 (C), 153.0 (2×C), 153.1 (2×C), 172.6 (2×CO), 176.7 (CO), 177.1 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C20H21N2O5+ 369.1445; Found 369.1446. 5-Bromo-5'-phenyl-2'H-spiro[indole-3,3'-pyrrolidine]-2,2'(1H)-dione (3c) was obtained from 2p (88 mg, 0.185 mmol). Reaction time 114 h. Yield 28 mg (42%); beige solid, mp 290–291 °C; dr 55:45; Rf = 0.66 (ethyl acetate). 1H NMR (600 MHz, DMSO-d6) δ = 2.26 (dd, 2J = 13.2, 3J = 8.2 Hz, 1H, CH2, A), 2.33 (dd, 2J = 13.3, 3J = 8.5 Hz, 1H, CH2, B), 2.75 (dd, 2J = 13.3, 3J = 7.5 ACS Paragon Plus Environment

Page 37 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Hz, 1H, CH2, B), 2.93 (dd, 2J = 13.2, 3J = 7.0 Hz, 1H, CH2, A), 5.03 (dd, 3J = 8.2, 3J = 7.0 Hz, 1H, CH, A), 5.22 (dd, 3J = 8.5, 3J = 7.5 Hz, 1H, CH, B), 6.81 (d, 3J = 8.2 Hz, 1H, Ar, A), 6.84 (d, 3

J = 8.3 Hz, 1H, Ar, B), 7.31–7.37 (m, 1H+1H, Ar, A, B), 7.38–7.48 (m, Ar, 4H+5H, Ar, A, B),

7.50–7.55 (m, 2H, Ar, A), 7.67 (d, 4J = 1.9 Hz, 1H, Ar, B), 8.81 (s, 1H, NH, B), 8.86 (s, 1H, NH, A), 10.71 (br.s, 1H, NH, B), 10.75 (br.s, 1H, NH, A). 13C NMR (150 MHz, DMSO-d6) δ = 40.4 (CH2), 40.9 (CH2), 54.8 (2×CH), 59.0 (C), 111.3 (CH), 111.5 (CH), 113.6 (2×C), 125.9 (CH), 126.2 (2×CH), 126.6 (2×CH), 126.8 (CH), 127.7 (CH), 127.8 (CH), 128.59 (3×CH), 128.64 (2×CH), 131.3 (2×CH), 132.3 (C), 133.6 (C), 141.9 (C), 142.2 (C), 142.5 (C), 142.7 (C), 172.0 (CO), 172.1 (CO), 176.3 (CO), 176.6 (CO). HRMS (ESI) m/z: [M + H]+ Calcd for C17H14BrN2O2+ 357.0233; Found 357.0238. ASSOCIATED CONTENT Supporting Information The Supporting Information is available free of charge on the ACS Publications website. X-ray data, results of cell assay and DFT calculations, NMR spectra (PDF) Accession Codes CCDC 1832110 contains the supplementary crystallographic data for this paper (2q). These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif AUTHOR INFORMATION Corresponding Author *E-mail: [email protected]. ORCID Konstantin L. Ivanov: 0000-0002-1557-175X Dmitry A. Skvortsov: 0000-0001-8336-8596 Stanislav I. Bezzubov: 0000-0002-2017-517X Ekaterina M. Budynina: 0000-0003-1193-7061 Notes The authors declare no competing financial interest. ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACKNOWLEDGMENT This research was supported by the Russian Science Foundation, grant number 17-73-10418. The NMR measurements were carried out at the Center for Magnetic Tomography and Spectroscopy, Faculty of Fundamental Medicine of Lomonosov Moscow State University. REFERENCES (1)

Reissig, H.; Zimmer, R. Donor−Acceptor-Substituted Cyclopropane Derivatives and Their Application in Organic Synthesis. Chem. Rev. 2003, 103 (4), 1151–1196.

(2)

For selected reviews on DA cyclopropanes, see: (a) Grover, H. K.; Emmett, M. R.; Kerr, M. A. Carbocycles from Donor–acceptor Cyclopropanes. Org. Biomol. Chem. 2015, 13 (3), 655–671. (b) Novikov, R. A.; Tomilov, Yu. V. Dimerization of Donor–acceptor Cyclopropanes. Mendeleev Commun. 2015, 25 (1), 1–10. (c) Cavitt, M. A.; Phun, L. H.; France, S. Intramolecular Donor–acceptor Cyclopropane Ring-Opening Cyclizations. Chem. Soc. Rev. 2014, 43 (3), 804–818. (d) Schneider, T. F.; Kaschel, J.; Werz, D. B. A New Golden Age for Donor–Acceptor Cyclopropanes. Angew. Chem. Int. Ed. 2014, 53 (22), 5504–5523. (e) de Nanteuil, F.; De Simone, F.; Frei, R.; Benfatti, F.; Serrano, E.; Waser, J. Cyclization and Annulation Reactions of Nitrogen-Substituted Cyclopropanes and Cyclobutanes. Chem. Commun. 2014, 50 (75), 10912–10928. (f) Wang, Z. Polar Intramolecular Cross-Cycloadditions of Cyclopropanes toward Natural Product Synthesis. Synlett 2012, 23 (16), 2311–2327.

(3)

Budynina, E. M.; Ivanov, K. L.; Sorokin, I. D.; Melnikov, M. Ya. Ring Opening of Donor–Acceptor Cyclopropanes with N-Nucleophiles. Synthesis 2017, 49 (14), 3035– 3068.

(4)

(a) Nambu, H.; Hirota, W.; Fukumoto, M.; Tamura, T.; Yakura, T. An Efficient Route to Highly Substituted Indoles via Tetrahydroindol-4(5H)-One Intermediates Produced by Ring-Opening Cyclization of Spirocyclopropanes with Amines. Chem. Eur. J. 2017, 23 (66), 16799–16805. (b) Das, S.; Daniliuc, C. G.; Studer, A. Stereospecific 1,3Aminobromination of Donor–Acceptor Cyclopropanes. Angew. Chem. Int. Ed. 2017, 56 (38), 11554–11558. (c) Xia, Y.; Lin, L.; Chang, F.; Liao, Y.; Liu, X.; Feng, X. Asymmetric Ring Opening/Cyclization/Retro-Mannich Reaction of Cyclopropyl Ketones with Aryl 1,2-Diamines for the Synthesis of Benzimidazole Derivatives. Angew. Chem. Int. Ed. 2016, 55 (40), 12228–12232. (d) Tejeda, J. E. C.; Landschoot, B. K.; Kerr, M. A. Radical Cyclizations for the Synthesis of Pyrroloindoles: Progress toward the Flinderoles. ACS Paragon Plus Environment

Page 38 of 42

Page 39 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

Org. Lett. 2016, 18 (9), 2142–2145. (e) Afanasyev, O. I.; Tsygankov, A. A.; Usanov, D. L.; Chusov, D. Dichotomy of Reductive Addition of Amines to Cyclopropyl Ketones vs Pyrrolidine Synthesis. Org. Lett. 2016, 18 (22), 5968–5970. (f) Han, J.-Q.; Zhang, H.-H.; Xu, P.-F.; Luo, Y.-C. Lewis Acid and (Hypo)iodite Relay Catalysis Allows a Strategy for the Synthesis of Polysubstituted Azetidines and Tetrahydroquinolines. Org. Lett. 2016, 18 (20), 5212–5215. (5)

(a) Sathishkannan, G.; Tamilarasan, V. J.; Srinivasan, K. Nucleophilic Ring-Opening Reactions of trans-2-Aroyl-3-aryl-cyclopropane-1,1-dicarboxylates with Hydrazines. Org. Biomol. Chem. 2017, 15 (6), 1400–1406. (b) Xue, S.; Liu, J.; Qing, X.; Wang, C. Brönsted Acid-Mediated Annulations of 1-Cyanocyclopropane-1-carboxylates with Arylhydrazines: Efficient Strategy for the Synthesis of 1,3,5-Trisubstituted Pyrazoles. RSC Adv. 2016, 6 (72), 67724–67728. (c) Lebold, T. P.; Kerr, M. A. Stereodivergent Synthesis of Fused Bicyclopyrazolidines: Access to Pyrazolines and Pyrrolidines. Org. Lett. 2009, 11 (19), 4354–4357. (d) Cao, W.; Zhang, H.; Chen, J.; Deng, H.; Shao, M.; Lei, L.; Qian, J.; Zhu, Y. A Facile Preparation of trans-1,2-Cyclopropanes Containing p-Trifluoromethylphenyl Group and Its Application to the Construction of Pyrazole and Cyclopropane Ring Fused Pyridazinone Derivatives. Tetrahedron 2008, 64 (28), 6670–6674.

(6)

(a) Liu, R.-R.; Ye, S.-C.; Lu, C.-J.; Xiang, B.; Gao, J.; Jia, Y.-X. Au-Catalyzed RingOpening Reactions of 2-(1-Alkynyl-cyclopropyl)pyridines with Nucleophiles. Org. Biomol. Chem. 2015, 13 (17), 4855–4858. (b) Zhang, J.; Schmalz, H.-G. Gold(I)Catalyzed Reaction of 1-(1-Alkynyl)-cyclopropyl Ketones with Nucleophiles: A Modular Entry to Highly Substituted Furans. Angew. Chem. Int. Ed. 2006, 45 (40), 6704–6707.

(7)

(a) Schobert, R.; Gordon, G. J.; Bieser, A.; Milius, W. 3-Functionalized Tetronic Acids From Domino Rearrangement/Cyclization/Ring-Opening Reactions of Allyl Tetronates. Eur. J. Org. Chem. 2003, 2003 (18), 3637–3647. (b) Vankar, Y. D.; Kumaravel, G.; Rao, C. T. Ritter Reaction with Cyclopropyl Ketones and Cyclopropyl Alcohols: Synthesis of N-Acyl-γ-keto and N-Acyl Homoallyl Amines. Synth. Commun. 1989, 19 (11–12), 2181– 2198. (c) Caputo, R.; Ferreri, C.; Palumbo, G.; Wenkert, E. Trimethylsilyl Tetrafluoroborate a Convenient Reagent for Solvolysis Reactions. Tetrahedron Lett. 1984, 25 (5), 577–578. (d) Pagenkopf, B. L.; Vemula, N. Cycloadditions of Donor–Acceptor Cyclopropanes and Nitriles. Eur. J. Org. Chem. 2017, 2017 (18), 2561–2567.

(8)

(a) Garve, L. K. B.; Jones, P. G.; Werz, D. B. Ring-Opening 1-Amino-3aminomethylation of Donor–Acceptor Cyclopropanes via 1,3-Diazepanes. Angew. Chem. ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Int. Ed. 2017, 56 (31), 9226–9230. (b) Garve, L. K. B.; Kreft, A.; Jones, P. G.; Werz, D. B. Synthesis of 2-Unsubstituted Pyrrolidines and Piperidines from Donor–Acceptor Cyclopropanes and Cyclobutanes: 1,3,5-Triazinanes as Surrogates for Formylimines. J. Org. Chem. 2017, 82 (17), 9235–9242. (c) Preindl, J.; Chakrabarty, S.; Waser, J. Dearomatization of Electron Poor Six-Membered N-Heterocycles through [3 + 2] Annulation with Aminocyclopropanes. Chem. Sci. 2017, 8 (10), 7112–7118. (d) Niu, H.; Du, C.; Xie, M.; Wang, Y.; Zhang, Q.; Qu, G.; Guo, H. Diversity-Oriented Synthesis of Acyclic Nucleosides via Ring-Opening of Vinyl Cyclopropanes with Purines. Chem. Commun. 2015, 51 (16), 3328–3331. (9)

(a) Akaev, A. A.; Villemson, E. V.; Vorobyeva, N. S.; Majouga, A. G.; Budynina, E. M.; Melnikov, M. Ya. 3-(2-Azidoethyl)oxindoles: Advanced Building Blocks for One-Pot Assembly of Spiro[pyrrolidine-3,3′-oxindoles]. J. Org. Chem. 2017, 82 (11), 5689–5701. (b) Ivanov, K. L.; Villemson, E. V.; Budynina, E. M.; Ivanova, O. A.; Trushkov, I. V; Melnikov, M. Ya. Ring Opening of Donor–Acceptor Cyclopropanes with the Azide Ion: A Tool for Construction of N-Heterocycles. Chem. Eur. J. 2015, 21 (13), 4975–4987. (c) Flisar, M. E.; Emmett, M. R.; Kerr, M. A. Catalyst-Free Tandem Ring-Opening/Click Reaction of Acetylene-Bearing Donor–Acceptor Cyclopropanes. Synlett 2014, 25 (16), 2297–2300. (d) Emmett, M. R.; Grover, H. K.; Kerr, M. A. Tandem Ring-Opening Decarboxylation of Cyclopropane Hemimalonates with Sodium Azide: A Short Route to γ-Aminobutyric Acid Esters. J. Org. Chem. 2012, 77 (15), 6634–6637. (e) Izquierdo, M. L.; Arenal, I.; Bernabé, M.; Fernández Alvarez, E. Synthesis of E and Z 1-Amino-2aryl(alkyl)-cyclopropanecarboxylic Acids via Meldrum Derivatives. Tetrahedron 1985, 41 (1), 215–220.

(10)

(a) Zhao, Y.; Aguilar, A.; Bernard, D.; Wang, S. Small-Molecule Inhibitors of the MDM2–p53 Protein–Protein Interaction (MDM2 Inhibitors) in Clinical Trials for Cancer Treatment. J. Med. Chem. 2015, 58 (3), 1038–1052. (b) Yu, B.; Yu, D.-Q.; Liu, H.-M. Spirooxindoles: Promising Scaffolds for Anticancer Agents. Eur. J. Med. Chem. 2015, 97, 673–698. (c) Santos, M. M. M. Recent Advances in the Synthesis of Biologically Active Spirooxindoles. Tetrahedron 2014, 70 (52), 9735–9757. (d) Galliford, C. V.; Scheidt, K. A. Pyrrolidinyl-Spirooxindole Natural Products as Inspirations for the Development of Potential Therapeutic Agents. Angew. Chem. Int. Ed. 2007, 46 (46), 8748–8758.

(11)

(a) Graziano, M. L.; Iesce, M. R. Ring-opening Reactions of Cyclopropanes. Part 1. Formal [3+2] Cycloaddition of trans-Ethyl 2,2-Dimethoxy-3-methylcyclopropane-1carboxylate to Phenyl Isocyanate. J. Chem. Res. (S) 1987, No. 11, 362–363. (b) Graziano, ACS Paragon Plus Environment

Page 40 of 42

Page 41 of 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Organic Chemistry

M. L.; Cimminiello, G. Ring-opening Reactions of Cyclopropanes. Part 2. Investigation on the Reactivity of Ethyl 2,2-Dimethoxy-cyclopropane-1-carboxylates towards Phenyl Isothiocyanate. J. Chem. Res. (S) 1989, No. 2, 42–43. (12)

Brückner, C.; Suchland, B.; Reißig, H.-U. Eine neue Synthese von Pyrrolderivaten. Liebigs Ann. der Chemie 1988, 1988 (5), 471–473.

(13)

Yamamoto, K.; Ishida, T.; Tsuji, J. Palladium(0)-catalyzed Cycloaddition of Activated Vinylcyclopropanes with Aryl Isocyanates. Chem. Lett. 1987, No. 6, 1157–1158.

(14)

Goldberg, A. F. G.; O’Connor, N. R.; Craig II, R. A.; Stoltz, B. M. Lewis Acid Mediated (3 + 2) Cycloadditions of Donor–Acceptor Cyclopropanes with Heterocumulenes. Org. Lett. 2012, 14 (20), 5314–5317.

(15)

Marti, C.; Carreira, E. M. Total Synthesis of (−)-Spirotryprostatin B: Synthesis and Related Studies. J. Am. Chem. Soc. 2005, 127 (32), 11505–11515.

(16)

Grover, H. K.; Emmett, M. R.; Kerr, M. A. γ-Substituted Butanolides from Cyclopropane Hemimalonates: An Expedient Synthesis of Natural (R)-Dodecan-4-olide. Org. Lett. 2013, 15 (18), 4838–4841.

(17)

Meloche, J. L.; Ashfeld, B. L. A Rhodium(II)-Catalyzed Formal [4+1]-Cycloaddition toward Spirooxindole Pyrrolone Construction Employing Vinyl Isocyanates as 1,4Dipoles. Angew. Chem. Int. Ed. 2017, 56 (23), 6604–6608.

(18)

Danishefsky, S.; Singh, R. K. Highly Activated Cyclopropane for Homoconjugate Reactions. J. Am. Chem. Soc. 1975, 97 (11), 3239–3241.

(19)

See the Supporting Information

(20)

Li, G.; Zhou, G.; Zhang-Negrerie, D.; Du, Y.; Huang, J.; Zhao, K. Palladium(II) AcetateCatalyzed Dual C–H Functionalization and C–C Bond Formation: A Domino Reaction for the Synthesis of Functionalized (E)-Bisindole-2-ones from Diarylbut-2-ynediamides. Adv. Synth. Catal. 2016, 358 (22), 3534–3540.

(21)

Trost, B. M.; Brennan, M. K. Palladium Asymmetric Allylic Alkylation of Prochiral Nucleophiles: Horsfiline. Org. Lett. 2006, 8 (10), 2027–2030.

(22) Voituriez, A.; Pinto, N.; Neel, M.; Retailleau, P.; Marinetti, A. An Organocatalytic [3+2] Cyclisation Strategy for the Highly Enantioselective Synthesis of Spirooxindoles. Chem. Eur. J. 2010, 16 (42), 12541–12544. ACS Paragon Plus Environment

The Journal of Organic Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(23)

Andreani, A.; Granaiola, M.; Locatelli, A.; Morigi, R.; Rambaldi, M.; Varoli, L.; Vieceli Dalla Sega, F.; Prata, C.; Nguyen, T. L.; Bai, R.; Hamel, E. Cytotoxic Activities of Substituted 3-(3,4,5-Trimethoxybenzylidene)-1,3-dihydroindol-2-ones and Studies on Their Mechanisms of Action. Eur. J. Med. Chem. 2013, 64, 603–612.

ACS Paragon Plus Environment

Page 42 of 42