Silver-Catalyzed Radical Arylphosphorylation of Unactivated Alkenes

Article pubs.acs.org/joc

Cite This: J. Org. Chem. 2018, 83, 4681−4691

Silver-Catalyzed Radical Arylphosphorylation of Unactivated Alkenes: Synthesis of 3‑Phosphonoalkyl Indolines Deqiang Liang,*,†,‡ Dandan Ge,† Yanping Lv,† Wenzhong Huang,‡ Baoling Wang,‡ and Weili Li‡ †

Department of Chemistry, Kunming University, Kunming 650214, China Yunnan Engineering Technology Research Center for Plastic Films, Kunming 650214, China

‡

S Supporting Information *

ABSTRACT: A silver-catalyzed phosphorylation/cyclization cascade of N-allyl anilines was developed, allowing direct access to 3-phosphonoalkyl indolines, which were previously obtainable only via tedious procedures under harsh/toxic conditions. The unactivated double bond serves as the radical acceptor, whereas H-phosphonates or -phosphine oxides act as the radical precursor. This protocol features simple operation, broad substrate scope, and great exo selectivity, and a gram-scale synthesis could be readily carried out.

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INTRODUCTION Phosphorus is a fundamental element for life,1 and organophosphorus compounds have found wide applications in pharmaceuticals,2 as well as in agroindustry,3 material science,4 organic synthesis,5 and coordination chemistry.6 Therefore, significant efforts have been directed toward the incorporation of a phosphorus functionality into various organic systems.7,8 In this regard and the past decades, phosphorylation-based vicinal difunctionalization of activated alkenes has proven to be one of the most powerful strategies to construct functionalized phosphorus-containing molecules,9−12 while phosphorylative difunctionalization of unactivated alkenes has until recently remained a challenge.13 Indoles, including oxindoles and indolines, fall into a ubiquitous structural motif that unites a variety of natural alkaloids14 and clinical drugs.15 One of the major bases of pharmaceutical research and drug development is constituted by combining several biologically active segments in one molecule, and the combination of the indole motif and a phosphorus group results in a wide range of substances exhibiting promising activity as anticancer,16 PET imaging,17 anti-HIV,18 antiviral,19 antimycobacterial,20 psychotropic,21 and mitochondria targeting agents.22 Such benefits continue to motivate the development of new methodologies leading to phosphorus-containing indoles. For example, entries to 3phosphonomethyl oxindoles are well documented, and they could be furnished either by traditional derivatization of isatin or oxindole derivatives23 or by recently developed carbophosphorylation of activated alkenes of N-arylacrylamides11 (Scheme 1a) or acryl sulfonamides.12 On the other hand, Yang and co-workers established a pioneering radical aminophosphorylation of unactivated alkenes of 2-allylanilines toward 2-phosphonomethyl-N-sulfonyl indolines (Scheme 1b).13c In contrast, 3-phosphonoalkyl indolines so far could only be obtained via tedious procedures under harsh/toxic conditions (Scheme 1c).24 The direct elaboration to the title products © 2018 American Chemical Society

Scheme 1. Synthesis of Some Phosphorylated Indoles

from readily available materials in an atom- and stepeconomical manner remains an unmet challenge and is thus highly desirable. Received: February 16, 2018 Published: March 26, 2018 4681

DOI: 10.1021/acs.joc.8b00450 J. Org. Chem. 2018, 83, 4681−4691

Article

The Journal of Organic Chemistry Inspired by recent advances in unactivated alkene difunctionalization13 and given our interest in the synthesis of biologically active compounds,25 we envisioned that using an N-allyl group as the radical acceptor, a cascade phosphorylation−arylation sequence might be triggered, enabling preparation of 3phosphonomethyl indolines in one operation. Herein, we report the successful execution of this synthetic hypothesis, and the present protocol features simple operation, broad substrate scope, great exo selectivity, and ready availability of starting materials. Moreover, it is practical for it could proceed on a gram scale.

(entry 6), Oxone, PhI(OAc)2, or I2O5 (not shown) as the oxidant. Using BPO and AgNO3, reactions carried out in other solvents, including 1,2-dichloroethane (DCE, entry 7), tetrahydrofuran (THF, entry 8), N,N-dimethylformamide (DMF, entry 9), dimethyl sulfoxide (DMSO, entry 10), CH2Cl2, toluene, MeNO2, and acetone (not shown), also suffered from severe loss of the substrate, affording indoline 3a1 in only 0−24% yields. A silver catalyst is essential, and only trace amounts of 3a1 were generated in the absence of it (entry 11). AgOAc (entry 12) and Ag2CO3 (entry 13) are also robust catalysts for this tandem reaction, and use of them gave similar results to those obtained with AgNO3. The reaction catalyzed by Ag2O, however, was retarded, giving product 3a1 in only 48% yield after 12 h (entry 14). With other metal salts as the catalyst, such as CuI (entry 15), Cu(OAc)2, and FeCl3 (entry 16), which are frequently encountered in radical transformations, no desired product was formed. Finally, after a careful screening of a wide range of additives of different types, we found that the addition of 1 equiv of K2CO3 resulted in 73% yield and a better reproducibility (entry 17). Beneficial effects of a base on phosphorylation reactions were frequently observed, probably because it might facilitate deprotonation in either the phosphoryl radical-generating process8a,e,g or the aromative cyclization step.11a An attempt to improve the yield further either by utilizing a higher dosage of the catalyst or reagents or by raising the temperature to 110 °C met with no success. While this arylphosphorylation did not occur at 50 °C, reducing the loading of the catalyst or reagents led to diminished yields (not shown). It is worthy of notice that such synthesis could be readily carried out on a gram scale without noticeable loss of activity (note f), rendering it highly practical. A variety of 3-phosphonoalkyl indolines can be prepared in one step from allylated anilides bearing various N-aryl groups (Table 2). For example, N-(2-methylallyl)-N-phenylpropionamide reacted with dimethyl phosphonate 2a to afford the corresponding tethered phosphonate 3b in 68% yield, and N(2-methylallyl) anilides with a methyl, bromo, or chloro group at the para position of the N-aryl group also participated in this reaction smoothly, giving the expected 5-substituted indolines 3c1−3 in moderate to high yields. Ortho-substituted anilides proved to be challenging substrates, as reflected by the relatively modest yields of indolines 3d1,2 having a methyl or chloro group at the 7 position. A similar steric effect was observed in the reactions of allylated anilides derived from 2,4dimethylaniline, 4-bromo-2-chloroaniline, or 2-bromo-5-chloroaniline, and the corresponding disubstituted products 3e1−3 were provided in only poor to moderate yields. With an anilide bearing a meta-chloro group on the N-aryl ring, poor regioselectivity was observed, and 4-chloroindoline 3f and regioisomeric 6-chloroindoline 3f′ were produced in 45% and 36% yields, respectively. It is worth noting that the substrate derived from pyridin-4-amine also reacted to afford the expected 3-phosphonomethyl heterocycle 3g in 58% yield. Use of N-allylacetanilide, which is derived from 3-bromoprop1-ene rather than 2-methylallyl bromide, delivered 5-exo-trig product 3h in 47% yield, along with a phosphorylated indole 3h′ formed in 9% yield, which might arise from the further oxidation of the initial product 3h. Excellent exo/endo selectivity was always observed in all of the above cases, including the one concerning 3h and 3h′, and no formal 6endo-trig product was detected.

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RESULTS AND DISCUSSION Our investigation commenced with the radical cyclization of N(2-methylallyl)-N-phenylacetamide 1a (Table 1), which is Table 1. Optimization of Reaction Conditionsa

entry

catalyst

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17e

AgNO3 AgNO3 AgNO3 AgNO3 AgNO3 AgNO3 AgNO3 AgNO3 AgNO3 AgNO3 AgOAc Ag2CO3 Ag2O CuI FeCl3 AgNO3

oxidant

solvent

t (h)

yield (%)

TBHPc DTBP AIBN BPO K2S2O8 BPO BPO BPO BPO BPO BPO BPO BPO BPO BPO BPO

MeCN MeCN MeCN MeCN MeCN MeCN DCE THF DMF DMSO MeCN MeCN MeCN MeCN MeCN MeCN MeCN

12 12 6 6 3 2 3 12 12 12 12 3 3 12 12 12 3

24 (51)b 16 (48)b 48 46 64 (62)d 25 0 (trace)b 21 (38)b 24 (23)b trace (12)b trace (76)b 60 63 48 (23)b 0 (58)b 0 (8)b 73 (72)f

a Reaction conditions: 1a (1.0 mmol), 2a (2.0 mmol), catalyst (0.2 mmol), oxidant (2.0 mmol), solvent (5.0 mL), 80 °C, under argon. b Recovery of 1a. c5.0−6.0 mol/L in decane. dThe reaction time was prolonged to 12 h. eK2CO3 (1.0 mmol) was added. fThe reaction was performed using 5.3 mmol of 1a.

prepared from acetanilide and 2-methylallyl bromide. Exposure of 1a to 2 equiv of dimethyl phosphonate 2a and 20 mol % of AgNO3 in MeCN at 80 °C furnished phosphorylated indoline 3a1 in a low yield (entry 1), and no beneficial effect was observed under oxygen atmosphere (not shown). In an effort to improve the reaction efficiency, a survey of several oxidative initiators was conducted. While the results were even worse using anhydrous tert-butyl hydroperoxide (TBHP, entry 2), the cascade reaction was completed within 6 h with di-tert-butyl peroxide (DTBP, entry 3) or azobis(isobutyronitrile) (AIBN, entry 4) as the oxidant, providing the desired product 3a1 in moderate yields. We were pleased to find that use of benzoyl peroxide (BPO, entry 5) delivered 3a1 in a better yield of 64% within 3 h, and the yield could not be further improved by prolonging the reaction time. Rapid decomposition or polymerization of substrate 1a was noticed using K2S2O8 4682


Article

The Journal of Organic Chemistry Table 2. Scopes of N-Aryl and -Allyl Groupsa

Table 3. Scopes of N-PGs and Radical Precursorsa

a Reaction conditions: 1b−h (2.0 mmol), 2a (4.0 mmol), AgNO3 (0.4 mmol), BPO (4.0 mmol), K2CO3 (2.0 mmol), MeCN (10.0 mL), under argon, 80 °C, 3 h.

The scope of N-protecting groups (PGs) was also investigated (Table 3). It was found that reactions of dimethyl phosphonate 2a with acetyl-protected N-(2-methylallyl) anilines bearing an electron-neutral, electron-rich, or electrondeficient N-aryl group furnished the desired 3-phosphonoalkyl indolines 3a1−3 in 56−83% yields, and octanoyl-protected indoline 3i was provided as well in a high yield. An evaluation of various sulfonyl PGs revealed that alkylsulfonyl, such as methylsulfonyl and ethylsulfonyl, and arylsulfonyl groups, including phenylsulfonyl, tosyl, o-tolylsulfonyl, and (4bromophenyl)sulfonyl, were both tolerated, providing the corresponding products 3j−o in 37−91% yields. 1-(Methylsulfonyl)-5-phenylindoline 3j2 was delivered in an excellent yield, whereas a poor yield was achieved using (4bromophenyl)sulfonyl as the PG. Allylated 4-aminobiphenyl protected by N,N-dimethylsulfamoyl is also a competent substrate, and related sulfamoyl indoline 3p was produced in 65% yield. Subsequently, the cyclization was extended to other phosphoryl radical precursors. Diethyl phosphonate reacted with various 2-methylallylamines with different PGs and having an electron-neutral, electron-rich, or electron-deficient N-aryl group to afford title products 3q1−4 in moderate to high yields, while diphenylphosphine oxide also worked well as the phosphorus source to furnish indolines 3r1,2 in moderate yields. Unfortunately, we failed to isolate any pure product from the complex reaction mixtures of allyl anilines protected by a benzoyl, 2,4-dichlorobenzoyl, thiophene-2-sulfonyl, or methyl group, probably due to the high reactivities of radicals. Some control experiments were performed to probe the reaction mechanism (Scheme 2a). As might be expected, the phosphorylative cyclization of N-(2-methylallyl)-N-(p-tolyl)propionamide 1c1 with diphenylphosphine oxide under standard conditions was completed suppressed by adding 2 equiv of either 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) or 2,6-di-tert-butyl-4-methylphenol (BHT) as the radical

a Reaction conditions: 1 (2.0 mmol), 2 (4.0 mmol), AgNO3 (0.4 mmol), BPO (4.0 mmol), K2CO3 (2.0 mmol), MeCN (10.0 mL), under argon, 80 °C, 3 h.

Scheme 2. Mechanistic Investigations

scavenger. Furthermore, phosphoryl-TEMPO adduct 426 and phosphoryl-BHT adducts 527 and 5′27,28 were isolated in 12%, 8%, and 18% yields, respectively. On the basis of the above observations and previous reports, 10a,11c,13b a plausible mechanism is proposed (Scheme 2b). At the beginning, Hphosphonate or -phosphine oxide 2 reacts with AgNO3 to furnish the phosphoryl radical, addition of which to the Ntethered double bond leads to radical intermediate A with a newly formed C−P bond. Intramolecular radical tapping by the phenyl ring ensues, affording ring closure intermediate B. 4683


Article

The Journal of Organic Chemistry 3

J(C−P) = 2.1 Hz), 52.5 (d, 2J(C−P) = 6.7 Hz), 52.2 (d, 2J(C−P) = 6.8 Hz), 41.2 (d, 2J(C−P) = 3.0 Hz), 35.8 (d, 1J(C−P) = 137.3 Hz), 27.5 (d, 3J(C−P) = 6.7 Hz), 24.2; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.40; HRMS (ESI-TOF) Calcd for C14H20BrNO4P+ ([M + H]+) 376.0308. Found 376.0310. 3b, Dimethyl ((3-Methyl-1-propionylindolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.23 (t, J = 7.4 Hz, 3H), 1.51 (s, 3H), 2.05−2.22 (m, 2H), 2.41−2.58 (m, 2H), 3.59 (d, J = 10.9 Hz, 3H), 3.70 (d, J = 10.9 Hz, 3H), 3.78 (d, J = 10.8 Hz, 1H), 4.40 (d, J = 10.8 Hz, 1H), 7.05 (ddd, J = 0.9, 7.5, 7.4 Hz, 1H), 7.13 (d, J = 7.2 Hz, 1H), 7.21−7.25 (m, 1H), 8.22 (d, J = 8.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.3, 141.7, 138.8 (d, 3J(C−P) = 14.5 Hz), 128.4, 123.7, 121.9, 117.2, 60.0 (d, 3J(C−P) = 1.2 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.2 (d, 2 J(C−P) = 2.7 Hz), 35.9 (d, 1J(C−P) = 136.5 Hz), 29.2, 27.4 (d, 3J(C−P) = 6.4 Hz), 8.7; 31P{1H} NMR (162 MHz, CDCl3) δ = 30.08; HRMS (ESI-TOF) Calcd for C15H23NO4P+ ([M + H]+) 312.1359. Found 312.1375. 3c1, Dimethyl ((3,5-Dimethyl-1-propionylindolin-3-yl)methyl)phosphonate. White solid; mp 90−91 °C. 1H NMR (400 MHz, CDCl3) δ = 1.22 (t, J = 7.4 Hz, 3H), 1.50 (s, 3H), 2.03−2.21 (m, 2H), 2.32 (s, 3H), 2.39−2.57 (m, 2H), 3.61 (d, J = 10.9 Hz, 3H), 3.71 (d, J = 11.0 Hz, 3H), 3.77 (d, J = 10.8 Hz, 1H), 4.38 (d, J = 10.8 Hz, 1H), 6.92 (s, 1H), 7.03 (d, J = 8.2 Hz, 1H), 8.09 (d, J = 8.2 Hz, 1H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 172.0, 139.4, 139.0 (d, 3J(C−P) = 15.2 Hz), 133.4, 128.9, 122.4, 116.9, 60.2 (d, 3J(C−P) = 1.7 Hz), 52.3 (d, 2J(C−P) = 6.5 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.1 (d, 2J(C−P) = 3.0 Hz), 35.9 (d, 1J(C−P) = 136.1 Hz), 29.1, 27.3 (d, 3J(C−P) = 5.8 Hz), 21.1, 8.7; 31P{1H} NMR (162 MHz, CDCl3) δ = 30.20; HRMS (ESI-TOF) Calcd for C16H25NO4P+ ([M + H]+) 326.1516. Found 326.1514. 3c2, Dimethyl ((5-Bromo-3-methyl-1-propionylindolin-3-yl)methyl)phosphonate. White solid; mp 98−99 °C. 1H NMR (400 MHz, CDCl3) δ = 1.22 (t, J = 7.4 Hz, 3H), 1.51 (s, 3H), 2.03−2.19 (m, 2H), 2.38−2.57 (m, 2H), 3.61 (d, J = 10.9 Hz, 3H), 3.72 (d, J = 11.0 Hz, 3H), 3.79 (d, J = 10.8 Hz, 1H), 4.42 (d, J = 10.8 Hz, 1H), 7.23 (d, J = 1.8 Hz, 1H), 7.34 (dd, J = 2.1, 8.6 Hz, 1H), 8.12 (d, J = 8.6 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.4, 141.0 (d, 3 J(C−P) = 16.2 Hz), 140.9, 131.3, 125.3, 118.6, 115.9, 60.1 (d, 3J(C−P) = 1.6 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.2 (d, 2J(C−P) = 6.8 Hz), 41.2 (d, 2 J(C−P) = 2.8 Hz), 35.8 (d, 1J(C−P) = 137.3 Hz), 29.1, 27.4 (d, 3J(C−P) = 6.5 Hz), 8.6; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.42; HRMS (ESI-TOF) Calcd for C15H22BrNO4P+ ([M + H]+) 390.0464. Found 390.0446. 3c3, Dimethyl ((5-Chloro-3-methyl-1-propionylindolin-3-yl)methyl)phosphonate. White solid; mp 106−107 °C. 1H NMR (400 MHz, CDCl3) δ = 1.22 (t, J = 7.4 Hz, 3H), 1.51 (s, 3H), 2.03−2.19 (m, 2H), 2.39−2.57 (m, 2H), 3.61 (d, J = 10.9 Hz, 3H), 3.72 (d, J = 11.0 Hz, 3H), 3.79 (d, J = 10.8 Hz, 1H), 4.43 (d, J = 10.8 Hz, 1H), 7.08 (d, J = 1.8 Hz, 1H), 7.19 (dd, J = 2.2, 8.6 Hz, 1H), 8.16 (d, J = 8.6 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.3, 140.6 (d, 3 J(C−P) = 14.6 Hz), 140.4, 128.5, 128.3, 122.3, 118.1, 60.2 (d, 3J(C−P) = 1.6 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.3 (d, 2 J(C−P) = 2.9 Hz), 35.8 (d, 1J(C−P) = 137.3 Hz), 29.1, 27.3 (d, 3J(C−P) = 6.6 Hz), 8.6; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.44; HRMS (ESI-TOF) Calcd for C15H22ClNO4P+ ([M + H]+) 346.0969. Found 346.0972. 3d1, Dimethyl ((3,7-Dimethyl-1-propionylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.26 (t, J = 7.5 Hz, 3H), 1.46 (s, 3H), 1.93−2.15 (m, 2H), 2.26 (s, 3H), 2.51−2.67 (m, 2H), 3.66 (d, J = 10.9 Hz, 3H), 3.73 (d, J = 11.0 Hz, 3H), 3.80 (d, J = 11.0 Hz, 1H), 4.40 (d, J = 10.8 Hz, 1H), 6.95−6.99 (m, 1H), 7.04−7.08 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.9 (br), 142.3 (d, 3J(C−P) = 16.7 Hz), 140.5, 130.5, 129.4 (br), 125.4, 118.8, 61.8 (br), 52.3 (d, 2J(C−P) = 6.5 Hz), 52.2 (d, 2J(C−P) = 6.9 Hz), 42.5 (d, 2J(C−P) = 2.9 Hz), 33.8 (d, 1J(C−P) = 135.6 Hz), 29.2 (br), 24.3 (d, 3J(C−P) = 3.4 Hz), 20.5, 9.9; 31P{1H} NMR (162 MHz, CDCl3) δ = 30.39; HRMS (ESI-TOF) Calcd for C16H25NO4P+ ([M + H]+) 326.1516. Found 326.1531. 3d2, Dimethyl ((7-Chloro-3-methyl-1-propionylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ

Subsequent single-electron transfer (SET) from B to Ag+ releases the indoline product 3 as well as Ag(0) and a proton. Ag(0) is oxidized to Ag+ by BPO to finish the catalytic cycle.

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CONCLUSIONS To conclude, a one-pot silver-catalyzed radical cyclization of Nallylated anilines leading to 3-phosphonoalkyl indolines was developed. The unactivated double bond acted as the radical acceptor, while H-phosphonates or -phosphine oxides served as the radical precursor. Notable advantages of this reaction include simple operation, broad substrate scope, and great exo/ endo selectivity, and the reaction could be easily scaled up.

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EXPERIMENTAL SECTION

General. Chemicals were all purchased from commercial sources and used without treatment. Reactions were performed in oven-dried glassware under an Ar atmosphere and monitored by thin layer chromatography (TLC) using silica gel F254 plates. Compounds were visualized using UV irradiation at 365 nm. Products were purified by column chromatography over 300−400 mesh silica gel under a positive pressure of air. 1H, 13C, DEPT, 31P and 2D NMR spectra were recorded at 25 °C on a Bruker Ascend 400 spectrometer using TMS as internal standard. High-resolution mass spectra (HRMS) were obtained using a Bruker microTOF II Focus spectrometer (ESI). Synthesis of 3-Phosphonomethyl Indolines (3a1 as an example). A 35 mL Schlenk tube, equipped with a magnetic stirring bar, was charged under argon with dimethyl phosphonate 2a (440 mg, 4.0 mmol), BPO969 mg, 4.0 mmol), K2CO3 (276 mg, 2.0 mmol), AgNO3 (68 mg, 0.4 mmol), and N-(2-methylallyl)-N-phenylacetamide 1a (379 mg, 2.0 mmol), followed by the addition of MeCN (10.0 mL). The mixture was stirred at 80 °C for 3 h; then it was quenched with saturated aqueous Na2S2O3 (5.0 mL) and water (30.0 mL) and extracted with CH2Cl2 (20.0 mL) three times. The residue obtained after evaporation of the solvent was purified by column chromatography on silica gel with ethyl acetate as the eluent to afford dimethyl ((1-acetyl-3-methylindolin-3-yl)methyl)phosphonate 3a1 as a pale yellow oil (434 mg, 73% yield). 3a1, Dimethyl ((1-Acetyl-3-methylindolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.52 (s, 3H), 2.06−2.24 (m, 2H), 2.26 (s, 3H), 3.60 (d, J = 10.9 Hz, 3H), 3.70 (d, J = 11.0 Hz, 3H), 3.81 (d, J = 10.8 Hz, 1H), 4.40 (d, J = 10.8 Hz, 1H), 7.06 (ddd, J = 0.9, 7.4, 7.4 Hz, 1H), 7.14 (dd, J = 0.8, 7.4 Hz, 1H), 7.21−7.25 (m, 1H), 8.19 (d, J = 8.1 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 160.0, 141.4, 138.8 (d, 3J(C−P) = 14.4 Hz), 128.3, 123.9, 121.9, 117.1, 60.9 (d, 3J(C−P) = 2.0 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.1 (d, 2J(C−P) = 3.2 Hz), 35.9 (d, 1 J(C−P) = 136.6 Hz), 27.5 (d, 3J(C−P) = 6.7 Hz), 24.2; 31P{1H} NMR (162 MHz, CDCl3) δ = 30.03; HRMS (ESI-TOF) Calcd for C14H21NO4P+ ([M + H]+) 298.1203. Found 298.1205. 3a2, Dimethyl ((1-acetyl-3,5-dimethylindolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.50 (s, 3H), 2.05−2.23 (m, 2H), 2.24 (s, 3H), 2.32 (s, 3H), 3.61 (d, J = 10.9 Hz, 3H), 3.71 (d, J = 11.0 Hz, 3H), 3.79 (d, J = 10.8 Hz, 1H), 4.38 (d, J = 10.8 Hz, 1H), 6.93 (s, 1H), 7.03 (dd, J = 0.9, 8.2 Hz, 1H), 8.05 (d, J = 8.2 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 168.7, 139.1, 139.0 (d, 3J(C−P) = 14.8 Hz), 133.5, 128.8, 122.5, 116.9, 61.1 (d, 3J(C−P) = 2.0 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.1 (d, 2J(C−P) = 3.2 Hz), 35.9 (d, 1J(C−P) = 136.4 Hz), 27.3 (d, 3J(C−P) = 6.3 Hz), 24.1, 21.1; 31P{1H} NMR (162 MHz, CDCl3) δ = 30.17; HRMS (ESI-TOF) Calcd for C15H23NO4P+ ([M + H]+) 312.1359. Found 312.1358. 3a3, Dimethyl ((1-Acetyl-5-bromo-3-methylindolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.51 (s, 3H), 2.04−2.20 (m, 2H), 2.24 (s, 3H), 3.61 (d, J = 11.0 Hz, 3H), 3.72 (d, J = 11.0 Hz, 3H), 3.81 (d, J = 10.8 Hz, 1H), 4.42 (d, J = 10.8 Hz, 1H), 7.23 (d, J = 2.0 Hz, 1H), 7.33 (dd, J = 2.0, 8.6 Hz, 1H), 8.08 (d, J = 8.6 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 169.0, 141.1 (d, 3J(C−P) = 14.4 Hz), 140.7, 131.3, 125.3, 118.7, 116.1, 61.1 (d, 4684


Article

The Journal of Organic Chemistry

3g, Dimethyl ((3-Methyl-1-propionyl-2,3-dihydro-1H-pyrrolo[3,2c]pyridin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.23 (t, J = 7.3 Hz, 3H), 1.56 (s, 3H), 2.11−2.28 (m, 2H), 2.42−2.60 (m, 2H), 3.58 (d, J = 11.0 Hz, 3H), 3.72 (d, J = 11.0 Hz, 3H), 3.82 (d, J = 10.8 Hz, 1H), 4.46 (d, J = 10.8 Hz, 1H), 8.04 (brs, unexchangeable, 1H), 8.35 (s, 1H), 8.42 (d, J = 5.5 Hz, 1H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 173.3, 150.3, 148.4 (br), 144.1, 134.0 (brd, 3J(C−P) = 13.3 Hz), 111.4, 60.3, 52.4 (d, 2J(C−P) = 6.7 Hz), 52.2 (d, 2J(C−P) = 6.8 Hz), 40.5 (br), 36.0 (d, 1J(C−P) = 137.8 Hz), 29.4, 28.1 (d, 3J(C−P) = 7.7 Hz), 8.4; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.12; HRMS (ESI-TOF) Calcd for C14H22N2O4P+ ([M + H]+) 313.1312. Found 313.1316. 3h, Dimethyl ((1-Acetylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.92−2.03 (m, 1H), 2.25− 2.34 (m, 4H), 3.76−3.82 (m, 7H), 3.95−4.00 (m, 1H), 4.24−4.29 (m, 1H), 7.05 (dd, J = 7.4, 7.4 Hz, 1H), 7.17 (d, J = 7.4 Hz, 1H), 7.24 (dd, J = 7.9, 7.6 Hz, 1H), 8.20 (d, J = 8.1 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 168.8, 142.3, 133.7 (d, 3J(C−P) = 17.9 Hz), 128.5, 123.9, 123.4, 117.1, 55.0 (d, 3J(C−P) = 1.6 Hz), 52.6 (d, 2J(C−P) = 6.9 Hz), 52.5 (d, 2J(C−P) = 6.9 Hz), 34.9 (d, 2J(C−P) = 4.1 Hz), 30.3 (d, 1 J(C−P) = 138.4 Hz), 24.2; 31P{1H} NMR (162 MHz, CDCl3) δ = 31.24; HRMS (ESI-TOF) Calcd for C13H19NO4P+ ([M + H]+) 284.1046. Found 284.1045. 3h′, Dimethyl ((1-Acetyl-1H-indol-3-yl)methyl)phosphonate. White semisolid. 1H NMR (400 MHz, CDCl3) δ = 2.63 (s, 3H), 3.22 (d, J = 1.0 Hz, 1H), 3.27 (d, J = 1.0 Hz, 1H), 3.69 (s, 3H), 3.72 (s, 3H), 7.31 (ddd, J = 1.1, 7.4, 7.7 Hz, 1H), 7.37 (ddd, J = 1.4, 7.0, 7.4 Hz, 1H), 7.48 (d, J = 4.0 Hz, 1H), 7.55−7.57 (m, 1H), 8.44 (d, J = 8.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 168.5, 135.6, 130.1 (d, 3J(C−P) = 6.2 Hz), 125.5, 124.2 (d, 3J(C−P) = 8.8 Hz), 123.7, 118.8, 116.7, 111.9 (d, 2J(C−P) = 9.7 Hz), 50.0 (d, 2J(C−P) = 6.8 Hz), 24.0, 22.0 (d, 1J(C−P) = 143.2 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 28.60; HRMS (ESI-TOF) Calcd for C13H17NO4P+ ([M + H]+) 282.0890. Found 282.0890. 3i, Dimethyl ((3,5-Dimethyl-1-octanoylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 0.88 (t, J = 7.0 Hz, 3H), 1.22−1.42 (m, 8H), 1.50 (s, 3H), 1.69−1.76 (m, 2H), 2.03−2.22 (m, 2H), 2.32 (s, 3H), 2.37−2.50 (m, 2H), 3.62 (d, J = 10.9 Hz, 3H), 3.71 (d, J = 11.0 Hz, 3H), 3.78 (d, J = 10.8 Hz, 1H), 4.37 (d, J = 10.8 Hz, 1H), 6.92 (s, 1H), 7.03 (dd, J = 0.9, 8.2 Hz, 1H), 8.09 (d, J = 8.2 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 171.5, 139.4, 139.0 (d, 3J(C−P) = 15.2 Hz), 133.4, 128.9, 122.4, 117.0, 60.4 (d, 3J(C−P) = 1.8 Hz), 52.3 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.1 (d, 2J(C−P) = 3.1 Hz), 35.9, 35.8 (d, 1J(C−P) = 136.1 Hz), 31.8, 29.4, 29.2, 27.2 (d, 3J(C−P) = 5.5 Hz), 24.6, 22.7, 21.1, 14.1; 31 1 P{ H} NMR (162 MHz, CDCl3) δ = 30.25; HRMS (ESI-TOF) Calcd for C21H35NO4P+ ([M + H]+) 396.2298. Found 396.2294. 3j1, Dimethyl ((3,5-Dimethyl-1-(methylsulfonyl)indolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.50 (s, 3H), 2.11−2.26 (m, 2H), 2.32 (s, 3H), 2.93 (s, 3H), 3.60 (d, J = 10.9 Hz, 3H), 3.68 (d, J = 11.0 Hz, 3H), 3.71 (d, J = 11.0 Hz, 1H), 4.19 (d, J = 10.3 Hz, 1H), 6.99 (s, 1H), 7.03 (d, J = 8.2 Hz, 1H), 7.29 (d, J = 8.2 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 138.40, 138.37 (d, 3J(C−P) = 13.2 Hz), 133.3, 129.2, 123.8, 113.1, 62.2 (d, 3 J(C−P) = 3.2 Hz), 52.3 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.7 Hz), 41.1 (d, 2J(C−P) = 3.2 Hz), 35.2 (d, 1J(C−P) = 137.8 Hz), 34.3, 27.6 (d, 3 J(C−P) = 7.3 Hz), 20.9; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.70; HRMS (ESI-TOF) Calcd for C14H23NO5PS+ ([M + H]+) 348.1029. Found 348.1030. 3j2, Dimethyl ((3-Methyl-1-(methylsulfonyl)-5-phenylindolin-3yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.57 (s, 3H), 2.19−2.33 (m, 2H), 3.00 (s, 3H), 3.56 (d, J = 10.9 Hz, 3H), 3.67 (d, J = 11.0 Hz, 3H), 3.79 (d, J = 10.3 Hz, 1H), 4.29 (d, J = 10.3 Hz, 1H), 7.34 (dddd, J = 1.2, 1.2, 7.4, 7.3 Hz, 1H), 7.40−7.49 (m, 5H), 7.53−7.56 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.5, 140.2, 138.7 (d, 3J(C−P) = 12.2 Hz), 137.0, 128.9, 127.7, 127.3, 126.8, 122.1, 113.5, 62.3 (d, 3J(C−P) = 3.3 Hz), 52.3 (d, 2J(C−P) = 6.7 Hz), 52.1 (d, 2J(C−P) = 6.7 Hz), 41.2 (d, 2J(C−P) = 3.2 Hz), 35.3 (d, 1J(C−P) = 138.3 Hz), 34.8, 28.1 (d, 3J(C−P) = 8.3 Hz);

= 1.26 (t, J = 7.4 Hz, 3H), 1.47 (s, 3H), 1.94−2.15 (m, 2H), 2.52−2.67 (m, 2H), 3.68 (d, J = 10.9 Hz, 3H), 3.72 (d, J = 11.0 Hz, 3H), 3.87 (d, J = 11.1 Hz, 1H), 4.40 (d, J = 11.1 Hz, 1H), 7.07 (s, 1H), 7.08 (d, J = 1.4 Hz, 1H), 7.23−7.25 (m, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.2, 145.0 (d, 3J(C−P) = 16.2 Hz), 139.5, 129.7, 126.3, 124.7, 120.3, 62.4 (d, 3J(C−P) = 3.4 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.2 (d, 2 J(C−P) = 6.9 Hz), 43.0 (d, 2J(C−P) = 2.8 Hz), 33.8 (d, 1J(C−P) = 137.0 Hz), 29.0, 24.3 (d, 3J(C−P) = 3.6 Hz), 9.8; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.82; HRMS (ESI-TOF) Calcd for C15H22ClNO4P+ ([M + H]+) 346.0969. Found 346.0973. 3e1, Dimethyl ((3,5,7-tTrimethyl-1-propionylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.25 (t, J = 7.4 Hz, 3H), 1.45 (s, 3H), 1.91−2.14 (m, 2H), 2.23 (s, 3H), 2.30 (s, 3H), 2.49−2.65 (m, 2H), 3.67 (d, J = 10.9 Hz, 3H), 3.73 (d, J = 10.9 Hz, 3H), 3.78 (d, J = 11.0 Hz, 1H), 4.37 (d, J = 11.0 Hz, 1H), 6.77 (s, 1H), 6.88 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.8 (br), 142.4 (brd, 3J(C−P) = 17.0 Hz), 138.2, 135.1, 131.0, 129.0 (br), 119.5, 61.9 (br), 52.3 (d, 2J(C−P) = 6.5 Hz), 52.1 (d, 2J(C−P) = 6.9 Hz), 42.4 (d, 2J(C−P) = 2.8 Hz), 33.8 (d, 1J(C−P) = 135.4 Hz), 29.1 (br), 24.2 (d, 3J(C−P) = 3.1 Hz), 21.1, 20.4, 9.9; 31P{1H} NMR (162 MHz, CDCl3) δ = 30.50; HRMS (ESI-TOF) Calcd for C17H27NO4P+ ([M + H]+) 340.1672. Found 340.1672. 3e2, Dimethyl ((5-Bromo-7-chloro-3-methyl-1-propionylindolin3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.25 (t, J = 7.4 Hz, 3H), 1.47 (s, 3H), 1.92−2.12 (m, 2H), 2.49−2.65 (m, 2H), 3.68 (d, J = 11.0 Hz, 3H), 3.73 (d, J = 11.0 Hz, 3H), 3.85 (d, J = 11.2 Hz, 1H), 4.42 (d, J = 11.2 Hz, 1H), 7.19 (d, J = 1.8 Hz, 1H), 7.41 (d, J = 1.8 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.9, 146.4 (d, 3J(C−P) = 16.2 Hz), 138.9, 132.1, 125.7, 123.9, 117.9, 62.2 (d, 3J(C−P) = 3.4 Hz), 52.4 (d, 2J(C−P) = 6.6 Hz), 52.3 (d, 2J(C−P) = 6.9 Hz), 43.3 (d, 2J(C−P) = 2.6 Hz), 33.7 (d, 1J(C−P) = 137.6 Hz), 28.9, 24.3 (d, 3J(C−P) = 3.8 Hz), 9.7; 31P{1H} NMR (162 MHz, CDCl 3 ) δ = 29.14; HRMS (ESI-TOF) Calcd for C15H21BrClNO4P+ ([M + H]+) 424.0075. Found 424.0076. 3e3, Dimethyl ((7-Bromo-4-chloro-3-methyl-1-propionylindolin3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.26 (t, J = 7.4 Hz, 3H), 1.61 (s, 3H), 2.09 (dd, J = 15.7, 17.7 Hz, 1H), 2.49−2.67 (m, 3H), 3.65 (d, J = 10.9 Hz, 3H), 3.75 (d, J = 11.0 Hz, 3H), 3.83 (d, J = 11.2 Hz, 1H), 4.58 (d, J = 11.2 Hz, 1H), 6.94 (d, J = 8.6 Hz, 1H), 7.36 (d, J = 8.6 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.8, 143.3, 139.9 (d, 3J(C−P) = 16.0 Hz), 133.8, 128.7, 127.6, 112.0, 61.2 (d, 3J(C−P) = 1.0 Hz), 52.4 (d, 2 J(C−P) = 6.6 Hz), 52.3 (d, 2J(C−P) = 6.9 Hz), 45.0 (d, 2J(C−P) = 2.5 Hz), 31.2 (d, 1J(C−P) = 136.6 Hz), 29.3, 23.4 (d, 3J(C−P) = 5.5 Hz), 9.6; 31 1 P{ H} NMR (162 MHz, CDCl3) δ = 29.63; HRMS (ESI-TOF) Calcd for C15H21BrClNO4P+ ([M + H]+) 424.0075. Found 424.0072. 3f, Dimethyl ((4-Chloro-3-methyl-1-propionylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.22 (t, J = 7.4 Hz, 3H), 1.67 (s, 3H), 2.32−2.61 (m, 4H), 3.52 (d, J = 10.9 Hz, 3H), 3.71 (d, J = 11.0 Hz, 3H), 3.77 (d, J = 10.8 Hz, 1H), 4.55 (d, J = 10.8 Hz, 1H), 6.97 (dd, J = 0.8, 8.0 Hz, 1H), 7.17 (dd, J = 8.1, 8.1 Hz, 1H), 8.23 (d, J = 8.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.4, 144.1, 133.6 (d, 3J(C−P) = 12.3 Hz), 129.9, 129.8, 125.0, 115.8, 60.2 (d, 3J(C−P) = 1.0 Hz), 52.4 (d, 2J(C−P) = 6.7 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 42.5, 33.2 (d, 1J(C−P) = 137.0 Hz), 29.3, 26.2 (d, 3 J(C−P) = 9.4 Hz), 8.6; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.92; HRMS (ESI-TOF) Calcd for C15H22ClNO4P+ ([M + H]+) 346.0969. Found 346.0964. 3f′, Dimethyl ((6-Chloro-3-methyl-1-propionylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.23 (t, J = 7.4 Hz, 3H), 1.50 (s, 3H), 2.02−2.19 (m, 2H), 2.39−2.57 (m, 2H), 3.61 (d, J = 10.9 Hz, 3H), 3.71 (d, J = 11.0 Hz, 3H), 3.79 (d, J = 10.8 Hz, 1H), 4.43 (d, J = 10.8 Hz, 1H), 7.00−7.05 (m, 2H), 8.28 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.5, 142.7, 137.2 (d, 3 J(C−P) = 13.9 Hz), 134.0, 123.6, 122.7, 117.5, 60.4, 52.4 (d, 2J(C−P) = 6.6 Hz), 52.1 (d, 2J(C−P) = 6.8 Hz), 41.0 (d, 2J(C−P) = 1.8 Hz), 35.9 (d, 1 J(C−P) = 137.1 Hz), 29.2, 27.5 (d, 3J(C−P) = 6.6 Hz), 8.6; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.60; HRMS (ESI-TOF) Calcd for C15H22ClNO4P+ ([M + H]+) 346.0969. Found 346.0974. 4685


Article

The Journal of Organic Chemistry P{1H} NMR (162 MHz, CDCl3) δ = 29.50; HRMS (ESI-TOF) Calcd for C19H25NO5PS+ ([M + H]+) 410.1186. Found 410.1188. 3k, Dimethyl ((5-Bromo-1-(ethylsulfonyl)-3-methylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.42 (t, J = 7.4 Hz, 3H), 1.50 (s, 3H), 2.10−2.23 (m, 2H), 3.10−3.24 (m, 2H), 3.61 (d, J = 11.0 Hz, 3H), 3.70 (d, J = 11.0 Hz, 3H), 3.78 (d, J = 10.4 Hz, 1H), 4.27 (d, J = 10.4 Hz, 1H), 7.25−7.27 (m, 2H), 7.31 (dd, J = 1.9, 8.6 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.3, 140.2 (d, 3J(C−P) = 13.0 Hz), 131.4, 126.5, 115.5, 114.8, 62.0 (d, 3 J(C−P) = 3.3 Hz), 52.4 (d, 2J(C−P) = 6.7 Hz), 52.2 (d, 2J(C−P) = 6.7 Hz), 44.4, 41.3 (d, 2J(C−P) = 3.2 Hz), 35.1 (d, 1J(C−P) = 138.5 Hz), 27.7 (d, 3 J(C−P) = 7.6 Hz), 7.7; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.04; HRMS (ESI-TOF) Calcd for C14H22BrNO5PS+ ([M + H]+) 426.0134. Found 426.0133. 3l1, Dimethyl ((3-Methyl-1-(phenylsulfonyl)indolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.28 (s, 3H), 1.82 (dd, J = 15.6, 17.4 Hz, 1H), 2.04 (dd, J = 15.5, 18.6 Hz, 1H), 3.63 (d, J = 10.9 Hz, 3H), 3.64 (d, J = 10.9 Hz, 3H), 3.67 (d, J = 10.9 Hz, 1H), 4.13 (d, J = 10.9 Hz, 1H), 7.00−7.08 (m, 2H), 7.23 (ddd, J = 1.6, 7.2, 7.2 Hz, 1H), 7.44−7.49 (m, 2H), 7.56 (dddd, J = 1.2, 1.3, 7.5, 7.4 Hz, 1H), 7.67 (d, J = 8.1 Hz, 1H), 7.85−7.87 (m, 2H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 140.3, 139.2 (d, 3J(C−P) = 15.9 Hz), 137.0, 133.3, 129.1, 128.6, 127.3, 123.9, 122.8, 114.6, 61.7 (d, 3 J(C−P) = 3.4 Hz), 52.2 (d, 2J(C−P) = 6.7 Hz), 41.2 (d, 2J(C−P) = 3.2 Hz), 35.3 (d, 1J(C−P) = 136.7 Hz), 26.5 (d, 3J(C−P) = 4.0 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 29.72; HRMS (ESI-TOF) Calcd for C18H23NO5PS+ ([M + H]+) 396.1029. Found 396.1031. 3l2, Dimethyl ((3,5-Dimethyl-1-(phenylsulfonyl)indolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.25 (s, 3H), 1.77 (dd, J = 16.5, 17.4 Hz, 1H), 2.01 (dd, J = 15.6, 18.5 Hz, 1H), 2.28 (s, 3H), 3.64 (d, J = 10.9 Hz, 3H), 3.65 (d, J = 10.9 Hz, 3H), 3.66 (d, J = 10.9 Hz, 1H), 4.11 (d, J = 11.0 Hz, 1H), 6.85 (s, 1H), 7.03 (d, J = 8.2 Hz, 1H), 7.46 (dd, J = 7.8, 7.4 Hz, 2H), 7.53− 7.57 (m, 2H), 7.84 (d, J = 7.8 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.5 (d, 3J(C−P) = 16.2 Hz), 137.9, 136.9, 133.7, 133.2, 129.09, 129.06, 127.3, 123.3, 114.6, 61.8 (d, 3J(C−P) = 3.3 Hz), 52.20 (d, 2J(C−P) = 6.9 Hz), 52.19 (d, 2J(C−P) = 6.9 Hz), 41.2 (d, 2J(C−P) = 3.2 Hz), 35.3 (d, 1J(C−P) = 136.4 Hz), 26.4 (d, 3J(C−P) = 3.7 Hz), 21.0; 31 1 P{ H} NMR (162 MHz, CDCl3) δ = 29.81; HRMS (ESI-TOF) Calcd for C19H25NO5PS+ ([M + H]+) 410.1186. Found 410.1197. 3l3, Dimethyl ((5-Bromo-3-methyl-1-(phenylsulfonyl)indolin-3yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.26 (s, 3H), 1.78 (dd, J = 16.0, 17.2 Hz, 1H), 2.00 (dd, J = 15.6, 18.8 Hz, 1H), 3.63−3.68 (m, 7H), 4.14 (d, J = 11.0 Hz, 1H), 7.17 (s, 1H), 7.34 (d, J = 8.6 Hz, 1H), 7.49 (dd, J = 7.6, 7.6 Hz, 2H), 7.54−7.60 (m, 2H), 7.83 (d, J = 7.8 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 141.5 (d, 3J(C−P) = 15.8 Hz), 139.6, 136.7, 133.5, 131.4, 129.2, 127.3, 126.2, 116.4, 116.2, 61.8 (d, 3J(C−P) = 3.7 Hz), 52.3 (d, 2J(C−P) = 6.8 Hz), 52.2 (d, 2J(C−P) = 6.6 Hz), 41.3 (d, 2 J(C−P) = 3.0 Hz), 35.1 (d, 1J(C−P) = 137.5 Hz), 26.4 (d, 3J(C−P) = 4.0 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 29.06; HRMS (ESI-TOF) Calcd for C18H22BrNO5PS+ ([M + H]+) 474.0134. Found 474.0132. 3m, Dimethyl ((3-Methyl-1-tosylindolin-3-yl)methyl)phosphonate. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.30 (s, 3H), 1.82 (dd, J = 14.5, 17.2 Hz, 1H), 2.04 (dd, J = 15.5, 18.6 Hz, 1H), 2.37 (s, 3H), 3.64 (d, J = 11.0 Hz, 3H), 3.65 (d, J = 10.8 Hz, 1H), 3.66 (d, J = 10.9 Hz, 3H), 4.11 (d, J = 10.9 Hz, 1H), 7.01 (ddd, J = 0.9, 7.5, 7.4 Hz, 1H), 7.06 (dd, J = 1.2, 7.5 Hz, 1H), 7.20−7.22 (m, 1H), 7.25 (d, J = 8.1 Hz, 2H), 7.65 (d, J = 8.1 Hz, 1H), 7.73 (ddd, J = 1.7, 1.7, 8.3 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 144.2, 140.4, 139.3 (d, 3J(C−P) = 15.9 Hz), 134.0, 129.7, 128.5, 127.4, 123.8, 122.7, 114.6, 61.7 (d, 3J(C−P) = 3.5 Hz), 52.20 (d, 2J(C−P) = 6.7 Hz), 52.19 (d, 2J(C−P) = 6.6 Hz), 41.2 (d, 2J(C−P) = 3.2 Hz), 35.3 (d, 1J(C−P) = 136.7 Hz), 26.4 (d, 3J(C−P) = 3.8 Hz), 21.5; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.76; HRMS (ESI-TOF) Calcd for C19H25NO5PS+ ([M + H]+) 410.1186. Found 410.1189. 3n, Dimethyl ((3,5-Dimethyl-1-(o-tolylsulfonyl)indolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.38 (s, 3H), 1.95 (dd, J = 15.6, 17.2 Hz, 1H), 2.09 (dd, J = 15.5, 18.6 Hz, 1H), 2.29 (s, 3H), 2.62 (s, 3H), 3.64 (s, 3H), 3.67 (s, 3H), 31

3.70 (d, J = 10.8 Hz, 1H), 4.14 (d, J = 10.8 Hz, 1H), 6.91 (s, 1H), 6.96−6.99 (m, 1H), 7.28−7.32 (m, 3H), 7.44 (ddd, J = 1.3, 7.7, 7.5 Hz, 1H), 7.97 (dd, J = 1.0, 8.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.3 (d, 3J(C−P) = 16.4 Hz), 138.6, 138.2, 137.4, 133.4, 133.0, 132.9, 129.5, 128.9, 126.3, 123.3, 114.6, 61.6 (d, 3J(C−P) = 3.3 Hz), 52.21 (d, 2J(C−P) = 6.6 Hz), 52.18 (d, 2J(C−P) = 6.8 Hz), 41.4 (d, 2 J(C−P) = 3.2 Hz), 35.2 (d, 1J(C−P) = 136.3 Hz), 26.2 (d, 3J(C−P) = 3.5 Hz), 21.0, 20.9; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.93; HRMS (ESI-TOF) Calcd for C20H27NO5PS+ ([M + H]+) 424.1342. Found 424.1357. 3o, Dimethyl ((1-((4-Bromophenyl)sulfonyl)-3-methylindolin-3yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.32 (s, 3H), 1.77 (dd, J = 15.6, 17.4 Hz, 1H), 2.03 (dd, J = 15.5, 18.7 Hz, 1H), 3.64 (d, J = 10.9 Hz, 3H), 3.65 (d, J = 10.9 Hz, 3H), 3.66 (d, J = 11.0 Hz, 1H), 4.15 (d, J = 11.0 Hz, 1H), 7.01− 7.09 (m, 2H), 7.23 (ddd, J = 1.6, 7.2, 8.1 Hz, 1H), 7.59−7.63 (m, 3H), 7.72 (ddd, J = 2.3, 2.0, 8.7 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.0, 139.3 (d, 3J(C−P) = 16.1 Hz), 136.0, 132.4, 128.8, 128.6, 128.4, 124.2, 122.9, 114.6, 61.6 (d, 3J(C−P) = 3.2 Hz), 52.2 (d, 2 J(C−P) = 6.7 Hz), 41.3 (d, 2J(C−P) = 3.1 Hz), 35.3 (d, 1J(C−P) = 136.8 Hz), 26.5 (d, 3J(C−P) = 4.0 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 29.49; HRMS (ESI-TOF) Calcd for C18H22BrNO5PS+ ([M + H]+) 474.0134. Found 474.0138. 3p, Dimethyl ((1-(N,N-Dimethylsulfamoyl)-3-methyl-5-phenylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.57 (s, 3H), 2.16−2.30 (m, 2H), 2.96 (s, 6H), 3.66 (d, J = 10.9 Hz, 3H), 3.70 (d, J = 11.0 Hz, 3H), 3.78 (d, J = 10.2 Hz, 1H), 4.27 (d, J = 10.2 Hz, 1H), 7.32 (dddd, J = 2.0, 1.9, 7.4, 7.3 Hz, 1H), 7.35 (dd, J = 1.2, 1.1 Hz, 1H), 7.40−7.44 (m, 4H), 7.52−7.55 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 141.2, 140.7, 138.8 (d, 3 J(C−P) = 15.0 Hz), 136.3, 128.8, 127.4, 127.1, 126.8, 121.4, 114.1, 62.5 (d, 3J(C−P) = 3.3 Hz), 52.3 (d, 2J(C−P) = 6.6 Hz), 52.2 (d, 2J(C−P) = 6.8 Hz), 41.4 (d, 2J(C−P) = 3.2 Hz), 38.3, 35.3 (d, 1J(C−P) = 136.9 Hz), 26.8 (d, 3J(C−P) = 5.2 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 29.90; HRMS (ESI-TOF) Calcd for C20H28N2O5PS+ ([M + H]+) 439.1451. Found 439.1452. 3q1, Diethyl ((1-Acetyl-3-methylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.24 (t, J = 7.1 Hz, 3H), 1.31 (t, J = 7.1 Hz, 3H), 1.52 (s, 3H), 2.05−2.23 (m, 2H), 2.25 (s, 3H), 3.80 (d, J = 10.8 Hz, 1H), 3.90−4.12 (m, 4H), 4.44 (d, J = 10.8 Hz, 1H), 7.05 (ddd, J = 0.9, 7.4, 7.4 Hz, 1H), 7.13 (d, J = 6.8 Hz, 1H), 7.20−7.25 (m, 1H), 8.19 (d, J = 8.0 Hz, 1H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 169.0, 141.5, 139.1 (d, 3J(C−P) = 14.5 Hz), 128.3, 123.9, 121.9, 117.2, 61.7 (d, 2J(C−P) = 6.6 Hz), 61.5 (d, 2J(C−P) = 6.7 Hz), 61.0 (d, 3J(C−P) = 1.8 Hz), 41.3 (d, 2J(C−P) = 3.2 Hz), 36.8 (d, 1J(C−P) = 136.6 Hz), 27.6 (d, 3J(C−P) = 6.3 Hz), 24.3, 16.41 (d, 3J(C−P) = 6.1 Hz), 16.37 (d, 3J(C−P) = 6.1 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 27.36; HRMS (ESI-TOF) Calcd for C16H25NO4P+ ([M + H]+) 326.1516. Found 326.1520. 3q2, Diethyl ((3,5-Dimethyl-1-propionylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.22 (t, J = 7.4 Hz, 3H), 1.25 (t, J = 7.1 Hz, 3H), 1.32 (t, J = 7.0 Hz, 3H), 1.51 (s, 3H), 2.07 (dd, J = 15.5, 17.3 Hz, 1H), 2.17 (dd, J = 15.6, 18.2 Hz, 1H), 2.32 (s, 3H), 2.39−2.56 (m, 2H), 3.77 (d, J = 10.8 Hz, 1H), 3.91−4.13 (m, 4H), 4.41 (d, J = 10.8 Hz, 1H), 6.93 (s, 1H), 7.02 (d, J = 8.1 Hz, 1H), 8.09 (d, J = 8.2 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.0, 139.3, 139.2 (d, 3J(C−P) = 15.1 Hz), 133.3, 128.8, 122.5, 116.8, 61.7 (d, 2J(C−P) = 6.6 Hz), 61.5 (d, 2J(C−P) = 6.7 Hz), 60.2 (d, 3J(C−P) = 1.7 Hz), 41.2 (d, 2J(C−P) = 3.2 Hz), 36.7 (d, 1J(C−P) = 136.2 Hz), 29.1, 27.4 (d, 3J(C−P) = 5.8 Hz), 21.1, 16.40 (d, 3J(C−P) = 6.2 Hz), 16.37 (d, 3J(C−P) = 6.1 Hz), 8.7; 31P{1H} NMR (162 MHz, CDCl3) δ = 27.51; HRMS (ESI-TOF) Calcd for C18H29NO4P+ ([M + H]+) 354.1829. Found 354.1828. 3q3, Diethyl ((5-Bromo-3-methyl-1-(phenylsulfonyl)indolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.25−1.29 (m, 9H), 1.79 (dd, J = 15.5, 17.7 Hz, 1H), 1.99 (dd, J = 15.4, 18.8 Hz, 1H), 3.67 (d, J = 10.9 Hz, 1H), 3.92−4.09 (m, 4H), 4.16 (d, J = 10.9 Hz, 1H), 7.17 (d, J = 2.0 Hz, 1H), 7.33 (dd, J = 2.0, 8.6 Hz, 1H), 7.45−7.51 (m, 2H), 7.54 (d, J = 8.9 Hz, 1H), 7.58 (dddd, J = 2.0, 2.0, 7.5, 7.4 Hz, 1H), 7.82−7.85 (m, 2H); 13C{1H} NMR (100 4686


Article

The Journal of Organic Chemistry MHz, CDCl3) δ = 141.6 (d, 3J(C−P) = 15.4 Hz), 139.6, 136.7, 133.5, 131.3, 129.2, 127.3, 126.3, 116.4, 116.1, 61.9 (d, 3J(C−P) = 3.7 Hz), 61.73 (d, 2J(C−P) = 6.4 Hz), 61.67 (d, 2J(C−P) = 6.5 Hz), 41.4 (d, 2J(C−P) = 3.2 Hz), 36.0 (d, 1J(C−P) = 137.7 Hz), 26.7 (d, 3J(C−P) = 4.4 Hz), 16.4 (d, 3J(C−P) = 6.2 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 26.33; HRMS (ESI-TOF) Calcd for C20H26BrNO5PS+ ([M + H]+) 502.0447. Found 502.0448. 3q4, Diethyl ((3-Methyl-1-tosylindolin-3-yl)methyl)phosphonate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.25−1.31 (m, 9H), 1.82 (dd, J = 15.5, 17.6 Hz, 1H), 2.04 (dd, J = 15.5, 18.6 Hz, 1H), 2.37 (s, 3H), 3.67 (d, J = 10.8 Hz, 1H), 3.96−4.05 (m, 4H), 4.13 (d, J = 10.8 Hz, 1H), 7.00 (ddd, J = 0.9, 7.5, 7.4 Hz, 1H), 7.06 (dd, J = 1.1, 7.5 Hz, 1H), 7.19−7.22 (m, 1H), 7.24 (d, J = 7.9 Hz, 2H), 7.64 (d, J = 8.1 Hz, 1H), 7.73 (ddd, J = 1.6, 1.6, 8.3 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 144.1, 140.4, 139.5 (d, 3J(C−P) = 15.9 Hz), 134.0, 129.7, 128.4, 127.4, 123.7, 122.7, 114.5, 61.7 (d, 3J(C−P) = 3.4 Hz), 61.61 (d, 2J(C−P) = 6.6 Hz), 61.58 (d, 2J(C−P) = 6.7 Hz), 41.3 (d, 2J(C−P) = 3.4 Hz), 36.2 (d, 1J(C−P) = 136.9 Hz), 26.6 (d, 3J(C−P) = 3.9 Hz), 21.5, 16.40 (d, 3J(C−P) = 6.1 Hz), 16.38 (d, 3J(C−P) = 6.1 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 27.09; HRMS (ESI-TOF) Calcd for C21H29NO5PS+ ([M + H]+) 438.1499. Found 438.1499. 3r1, 1-(3-((Diphenylphosphoryl)methyl)-3,5-dimethylindolin-1yl)propan-1-one. White semisolid. 1H NMR (400 MHz, CDCl3) δ = 1.17 (t, J = 7.4 Hz, 3H), 1.42 (s, 3H), 2.23 (s, 3H), 2.32−2.38 (m, 2H), 2.59−2.71 (m, 2H), 3.72 (d, J = 10.9 Hz, 1H), 4.56 (d, J = 10.9 Hz, 1H), 6.84 (s, 1H), 6.93 (d, J = 8.2 Hz, 1H), 7.35−7.55 (m, 6H), 7.58−7.63 (m, 2H), 7.77−7.82 (m, 2H), 7.99 (d, J = 8.2 Hz, 1H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 172.1, 139.4, 139.2 (d, 3J(C−P) = 10.9 Hz), 134.1 (d, 1J(C−P) = 97.2 Hz), 133.9 (d, 1J(C−P) = 97.8 Hz), 133.2, 131.7 (d, 4J(C−P) = 2.6 Hz), 131.6 (d, 4J(C−P) = 2.7 Hz), 130.5 (d, J(C−P) = 9.1 Hz), 130.3 (d, J(C−P) = 9.3 Hz), 128.82, 128.76 (d, J(C−P) = 11.9 Hz), 128.6 (d, J(C−P) = 11.7 Hz), 122.4, 116.9, 60.2 (d, 3 J(C−P) = 2.3 Hz), 42.9 (d, 2J(C−P) = 4.1 Hz), 40.1 (d, 1J(C−P) = 67.2 Hz), 29.0, 27.2 (d, 3J(C−P) = 4.1 Hz), 21.0, 8.7; 31P{1H} NMR (162 MHz, CDCl3) δ = 27.62; HRMS (ESI-TOF) Calcd for C26H29NO2P+ ([M + H]+) 418.1930. Found 418.1927. 3r2, ((3-Methyl-1-tosylindolin-3-yl)methyl)diphenylphosphine Oxide. White solid; mp 144−145 °C. 1H NMR (400 MHz, CDCl3) δ = 1.30 (s, 3H), 2.28 (s, 3H), 2.30 (dd, J = 11.4, 15.2 Hz, 1H), 2.58 (dd, J = 8.9, 15.2 Hz, 1H), 3.58 (d, J = 10.9 Hz, 1H), 4.21 (d, J = 10.8 Hz, 1H), 6.84 (ddd, J = 0.9, 7.5, 7.5 Hz, 1H), 7.03 (dd, J = 0.8, 7.6 Hz, 1H), 7.10−7.15 (m, 3H), 7.38−7.51 (m, 6H), 7.59−7.70 (m, 7H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 144.0, 140.4, 139.3 (d, 3J(C−P) = 11.2 Hz), 134.6 (d, 1J(C−P) = 97.9 Hz), 134.0, 133.9 (d, 1J(C−P) = 97.3 Hz), 131.7 (d, 4J(C−P) = 2.6 Hz), 131.5 (d, 4J(C−P) = 2.7 Hz), 130.4 (d, J(C−P) = 9.1 Hz), 130.3 (d, J(C−P) = 9.3 Hz), 129.7, 128.7 (d, J(C−P) = 11.6 Hz), 128.6 (d, J(C−P) = 11.6 Hz), 128.4, 127.4, 123.6, 123.1, 114.5, 62.4 (d, 3J(C−P) = 4.4 Hz), 43.0 (d, 2J(C−P) = 3.9 Hz), 39.5 (d, 1J(C−P) = 67.7 Hz), 26.0 (d, 3J(C−P) = 2.0 Hz), 21.5; 31P{1H} NMR (162 MHz, CDCl3) δ = 26.70; HRMS (ESI-TOF) Calcd for C29H29NO3PS+ ([M + H]+) 502.1600. Found 502.1605. 4,26 2,2,6,6-Tetramethylpiperidin-1-yl diphenylphosphinate. White semisolid. 1H NMR (400 MHz, CDCl3) δ = 1.09 (brs, 12H), 1.46 (brs, 1H), 1.56 (brs, 5H), 7.39−7.49 (m, 6H), 7.83−7.89 (m, 4H); 13C{1H} NMR (100 MHz, CDCl3) δ = 133.9 (d, 1J(C−P) = 134.2 Hz), 131.7 (d, 3J(C−P) = 9.4 Hz), 131.5 (d, 4J(C−P) = 2.8 Hz), 128.3 (d, 2 J(C−P) = 12.8 Hz), 61.6 (d, 3J(C−P) = 2.6 Hz), 40.1, 33.8 (br), 20.7 (br), 16.9; 31P{1H} NMR (162 MHz, CDCl3) δ = 33.51; HRMS (ESITOF) Calcd for C21H29NO2P+ ([M + H]+) 358.1930. Found 358.1936. 5,27 2,6-di-tert-Butyl-4-methylphenyl diphenylphosphinate. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.12 (s, 18H), 1.56 (d, J = 14.8 Hz, 3H), 6.65 (d, J = 5.0 Hz, 2H), 7.43−7.47 (m, 4H), 7.52−7.55 (m, 2H), 7.84−7.89 (m, 4H); 13C{1H} NMR (100 MHz, CDCl3) δ = 184.5 (d, J(C−P) = 6.0 Hz), 149.9 (d, J(C−P) = 8.6 Hz), 139.5 (d, 4J(C−P) = 4.1 Hz), 132.3 (d, 4J(C−P) = 2.8 Hz), 131.8 (d, 3J(C−P) = 8.0 Hz), 129.7 (d, 1J(C−P) = 94.6 Hz), 128.4 (d, 2J(C−P) = 11.5 Hz), 47.1 (d, J(C−P) = 57.3 Hz), 35.2 (d, 4J(C−P) = 1.4 Hz), 29.0, 19.9 (d, 6J(C−P) = 8.0 Hz); 31P{1H} NMR (162 MHz, CDCl3) δ = 31.61; HRMS (ESI-TOF) Calcd for C27H34O2P+ ([M + H]+) 421.2291. Found 421.2273.

5′,27,28 (3,5-Ditert-butyl-4-hydroxybenzyl)diphenylphosphine Oxide. White semisolid. 1H NMR (400 MHz, CDCl3) δ = 1.28 (s, 18H), 3.57 (d, J = 13.8 Hz, 2H), 5.08 (s, 1H), 6.74 (d, J = 2.2 Hz, 2H), 7.41−7.45 (m, 4H), 7.49−7.53 (m, 2H), 7.64−7.69 (m, 4H); 13C{1H} NMR (100 MHz, CDCl3) δ = 152.7 (d, J(C−P) = 3.4 Hz), 135.7 (d, J(C−P) = 2.8 Hz), 132.4 (d, 1J(C−P) = 97.3 Hz), 131.6 (d, 4J(C−P) = 2.7 Hz), 131.4 (d, 3J(C−P) = 8.9 Hz), 128.3 (d, 2J(C−P) = 11.5 Hz), 126.9 (d, 3 J(C−P) = 5.0 Hz), 121.2 (d, J(C−P) = 7.9 Hz), 38.1 (d, 1J(C−P) = 66.9 Hz), 34.1, 30.1; 31P{1H} NMR (162 MHz, CDCl3) δ = 29.87; HRMS (ESI-TOF) Calcd for C27H34O2P+ ([M + H]+) 421.2291. Found 421.2285. Preparation and Analytical Data of Substrates 1. Anilides, sulfonamides, and substrates 1 were prepared according to literature procedures.29 1a1, N-(2-Methylallyl)-N-phenylacetamide. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.76 (d, J = 0.3 Hz, 3H), 1.90 (s, 3H), 4.29 (s, 2H), 4.70 (s, 1H), 4.81 (s, 1H), 7.16 (d, J = 7.5 Hz, 2H), 7.32 (dd, J = 7.4, 7.2 Hz, 1H), 7.37−7.41 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 170.4, 143.1, 140.7, 129.5, 127.8, 113.1, 55.0, 22.8, 20.3; HRMS (ESI-TOF) Calcd for C12H16NO+ ([M + H]+) 190.1226. Found 190.1230. 1a2, N-(2-Methylallyl)-N-(p-tolyl)acetamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.75 (s, 3H), 1.89 (s, 3H), 2.36 (s, 3H), 4.26 (s, 2H), 4.69 (s, 1H), 4.81 (s, 1H), 7.04 (d, J = 8.2 Hz, 2H), 7.18 (d, J = 8.1 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 170.5, 140.8, 140.5, 137.6, 130.1, 127.5, 113.1, 55.0, 22.7, 21.0, 20.3; HRMS (ESI-TOF) Calcd for C13H18NO+ ([M + H]+) 204.1383. Found 204.1385. 1a3, N-(4-Bromophenyl)-N-(2-methylallyl)acetamide. Pale yellow solid; mp 51−52 °C. 1H NMR (400 MHz, CDCl3) δ = 1.74 (s, 3H), 1.90 (s, 3H), 4.25 (s, 2H), 4.68 (s, 1H), 4.83 (s, 1H), 7.05 (d, J = 8.4 Hz, 2H), 7.52 (d, J = 7.4 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 170.1, 142.1, 140.5, 132.7, 129.5, 121.6, 113.6, 54.9, 22.8, 20.3; HRMS (ESI-TOF) Calcd for C12H15BrNO+ ([M + H]+) 268.0332. Found 268.0328. 1b, N-(2-Methylallyl)-N-phenylpropionamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.06 (t, J = 7.4 Hz, 3H), 1.76 (d, J = 0.3 Hz, 3H), 2.11 (q, J = 7.2 Hz, 2H), 4.28 (s, 2H), 4.69 (s, 1H), 4.81 (s, 1H), 7.16 (d, J = 7.4 Hz, 2H), 7.32 (dd, J = 7.3, 7.2 Hz, 1H), 7.36− 7.41 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.8, 142.8, 140.9, 129.5, 128.0, 127.7, 113.1, 55.2, 27.8, 20.3, 9.8; HRMS (ESITOF) Calcd for C13H18NO+ ([M + H]+) 204.1383. Found 204.1384. 1c1, N-(2-Methylallyl)-N-(p-tolyl)propionamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.05 (t, J = 7.5 Hz, 3H), 1.75 (s, 3H), 2.11 (q, J = 7.5 Hz, 2H), 2.36 (s, 3H), 4.26 (s, 2H), 4.68 (s, 1H), 4.80 (s, 1H), 7.03 (d, J = 8.2 Hz, 2H), 7.18 (d, J = 8.0 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.9, 141.0, 140.1, 137.6, 130.1, 127.7, 113.0, 55.2, 27.8, 21.0, 20.3, 9.8; HRMS (ESI-TOF) Calcd for C14H20NO+ ([M + H]+) 218.1539. Found 218.1539. 1c2, N-(4-Bromophenyl)-N-(2-methylallyl)propionamide. Pale yellow solid; mp 72−73 °C. 1H NMR (400 MHz, CDCl3) δ = 1.07 (t, J = 7.3 Hz, 3H), 1.74 (s, 3H), 2.10 (d, J = 7.0 Hz, 2H), 4.25 (s, 2H), 4.67 (s, 1H), 4.82 (s, 1H), 7.04 (d, J = 8.1 Hz, 2H), 7.51 (d, J = 8.5 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.5, 141.8, 140.6, 132.7, 129.7, 121.5, 113.5, 55.1, 27.9, 20.3, 9.7; HRMS (ESITOF) Calcd for C13H17BrNO+ ([M + H]+) 282.0488. Found 282.0491. 1c3, N-(4-Chlorophenyl)-N-(2-methylallyl)propionamide. White solid; mp 73−74 °C. 1H NMR (400 MHz, CDCl3) δ = 1.07 (t, J = 7.3 Hz, 3H), 1.74 (s, 3H), 2.10 (d, J = 6.9 Hz, 2H), 4.25 (s, 2H), 4.67 (s, 1H), 4.82 (s, 1H), 7.09 (d, J = 8.2 Hz, 2H), 7.36 (d, J = 8.6 Hz, 2H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 173.5, 141.2, 140.6, 133.5, 129.7, 129.4, 113.5, 55.1, 27.9, 20.2, 9.7; HRMS (ESI-TOF) Calcd for C13H17ClNO+ ([M + H]+) 238.0993. Found 238.0992. 1d1, N-(2-Methylallyl)-N-(o-tolyl)propionamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.05 (t, J = 7.4 Hz, 3H), 1.80 (s, 3H), 1.85−1.95 (m, 1H), 1.99−2.09 (m, 1H), 2.22 (s, 3H), 3.47 (d, J = 14.5 Hz, 1H), 4.67 (s, 1H), 4.82 (s, 1H), 4.87 (d, J = 14.5 Hz, 1H), 7.06 (dd, J = 1.3, 7.6 Hz, 1H), 7.18−7.22 (m, 1H), 7.25 (ddd, J = 1.4, 7.5, 7.4 Hz, 1H), 7.28−7.30 (m, 1H); 13C{1H} NMR (100 MHz, CDCl3) 4687


Article

The Journal of Organic Chemistry δ = 173.9, 141.2, 140.8, 135.5, 131.4, 129.1, 128.2, 126.9, 113.6, 54.0, 27.4, 20.7, 17.5, 9.5; HRMS (ESI-TOF) Calcd for C14H20NO+ ([M + H]+) 218.1539. Found 218.1549. 1d2, N-(2-Chlorophenyl)-N-(2-methylallyl)propionamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.07 (t, J = 7.4 Hz, 3H), 1.79 (s, 3H), 1.94−2.08 (m, 2H), 3.55 (d, J = 14.7 Hz, 1H), 4.66 (s, 1H), 4.81 (s, 1H), 4.89 (d, J = 14.7 Hz, 1H), 7.18−7.24 (m, 1H), 7.27−7.34 (m, 2H), 7.48−7.53 (m, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.7, 140.7, 139.6, 133.2, 130.9, 130.6, 129.4, 127.7, 113.9, 53.8, 27.5, 20.6, 9.4; HRMS (ESI-TOF) Calcd for C13H17ClNO+ ([M + H]+) 238.0993. Found 238.0999. 1e1, N-(2,4-Dimethylphenyl)-N-(2-methylallyl)propionamide. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.05 (t, J = 7.4 Hz, 3H), 1.79 (s, 3H), 1.85−1.95 (m, 1H), 2.00−2.09 (m, 1H), 2.17 (s, 3H), 2.33 (s, 3H), 3.44 (d, J = 14.4 Hz, 1H), 4.67 (s, 1H), 4.81 (s, 1H), 4.86 (d, J = 14.5 Hz, 1H), 6.94 (d, J = 7.9 Hz, 1H), 7.00 (d, J = 7.9 Hz, 1H), 7.10 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 174.1, 140.9, 138.6, 138.0, 135.1, 132.0, 128.8, 127.5, 113.5, 54.1, 27.4, 21.0, 20.7, 17.4, 9.6; HRMS (ESI-TOF) Calcd for C15H22NO+ ([M + H]+) 232.1696. Found 232.1694. 1e2 , N-(4-Br omo-2 -chloro phenyl )-N-(2-methyl allyl )propionamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 1.07 (t, J = 7.4 Hz, 3H), 1.78 (s, 3H), 1.94−2.08 (m, 2H), 3.52 (d, J = 14.6 Hz, 1H), 4.65 (s, 1H), 4.82 (s, 1H), 4.88 (d, J = 14.7 Hz, 1H), 7.10 (d, J = 8.4 Hz, 1H), 7.45 (dd, J = 2.2, 8.4 Hz, 1H), 7.68 (d, J = 2.2 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.3, 140.4, 138.7, 134.3, 133.3, 132.0, 131.1, 122.3, 114.3, 53.7, 27.5, 20.5, 9.3; HRMS (ESI-TOF) Calcd for C13H16BrClNO+ ([M + H]+) 316.0098. Found 316.0081. 1e3 , N-(2-Br omo-5 -chloro phenyl )-N-(2-methyl allyl )propionamide. White solid; mp 56−57 °C. 1H NMR (400 MHz, CDCl3) δ = 1.09 (t, J = 7.4 Hz, 3H), 1.79 (s, 3H), 1.94−2.09 (m, 2H), 3.44 (d, J = 14.8 Hz, 1H), 4.67 (s, 1H), 4.86 (s, 1H), 4.93 (d, J = 14.8 Hz, 1H), 7.20 (d, J = 2.4 Hz, 1H), 7.24 (dd, J = 2.5, 8.6 Hz, 1H), 7.63 (d, J = 8.6 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.2, 142.2, 140.3, 134.6, 133.8, 131.1, 129.9, 122.1, 114.2, 53.8, 27.8, 20.6, 9.3; HRMS (ESI-TOF) Calcd for C13H16BrClNO+ ([M + H]+) 316.0098. Found 316.0095. 1f, N-(3-Chlorophenyl)-N-(2-methylallyl)propionamide. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.08 (t, J = 7.4 Hz, 3H), 1.75 (s, 3H), 2.13 (d, J = 3.4 Hz, 2H), 4.25 (s, 2H), 4.69 (s, 1H), 4.84 (s, 1H), 7.05−7.08 (m, 1H), 7.18 (s, 1H), 7.30−7.35 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.5, 144.0, 140.6, 134.8, 130.4, 128.2, 128.0, 126.3, 113.4, 55.2, 27.9, 20.3, 9.7; HRMS (ESI-TOF) Calcd for C13H17ClNO+ ([M + H]+) 238.0993. Found 238.0997. 1g, N-(2-Methylallyl)-N-(pyridin-4-yl)propionamide. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.13 (t, J = 7.4 Hz, 3H), 1.75 (d, J = 0.4 Hz, 3H), 2.29 (q, J = 7.4 Hz, 2H), 4.29 (s, 2H), 4.75 (s, 1H), 4.88−4.90 (m, 1H), 7.17 (dd, J = 1.6, 4.6 Hz, 2H), 8.62 (dd, J = 1.6, 4.6 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 173.3, 151.1, 150.4, 140.3, 121.4, 112.8, 54.7, 27.9, 20.2, 9.7; HRMS (ESI-TOF) Calcd for C12H17N2O+ ([M + H]+) 205.1335. Found 205.1336. 1h, N-Allyl-N-phenylacetamide. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.86 (s, 3H), 4.30 (ddd, J = 1.2, 1.2, 6.2 Hz, 2H), 5.04−5.12 (m, 2H), 5.82−5.92 (m, 1H), 7.16 (d, J = 7.3 Hz, 2H), 7.31−7.36 (m, 1H), 7.38−7.43 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 170.2, 143.0, 133.2, 129.6, 128.1, 127.9, 117.8, 52.0, 22.7; HRMS (ESI-TOF) Calcd for C11H14NO+ ([M + H]+) 176.1070. Found 176.1067. 1i, N-(2-Methylallyl)-N-(p-tolyl)octanamide. Colorless oil. 1H NMR (400 MHz, CDCl3) δ = 0.84 (t, J = 7.0 Hz, 3H), 1.17−1.28 (m, 8H), 1.55−1.63 (m, 2H), 1.75 (s, 3H), 2.10 (t, J = 7.5 Hz, 2H), 2.34 (s, 3H), 4.27 (s, 2H), 4.67 (s, 1H), 4.78 (s, 1H), 7.03 (d, J = 8.1 Hz, 2H), 7.17 (d, J = 8.1 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 172.8, 140.9, 140.1, 137.3, 129.9, 127.6, 112.9, 54.9, 34.1, 31.5, 29.1, 28.9, 25.4, 22.4, 20.8, 20.1, 13.9; HRMS (ESI-TOF) Calcd for C19H30NO+ ([M + H]+) 288.2322. Found 288.2317. 1j1, N-(2-Methylallyl)-N-(p-tolyl)methanesulfonamide. White solid; mp 153−154 °C. 1H NMR (400 MHz, CDCl3) δ = 1.76 (s, 3H), 2.34 (s, 3H), 2.89 (s, 3H), 4.22 (s, 2H), 4.80−4.81 (m, 2H), 7.17

(d, J = 8.4 Hz, 2H), 7.22 (ddd, J = 1.8, 2.3, 8.6 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.0, 137.9, 136.3, 129.9, 128.0, 115.0, 56.8, 37.1, 21.1, 19.8; HRMS (ESI-TOF) Calcd for C12H18NO2S+ ([M + H]+) 240.1053. Found 240.1057. 1j2, N-([1,1′-Biphenyl]-4-yl)-N-(2-methylallyl)methanesulfonamide. White solid; mp 134−135 °C. 1H NMR (400 MHz, CDCl3) δ = 1.78 (s, 3H), 2.94 (s, 3H), 4.29 (s, 2H), 4.84− 4.87 (m, 2H), 7.36 (dddd, J = 1.3, 1.3, 6.4, 8.2 Hz, 1H), 7.39−7.46 (m, 4H), 7.55−7.61 (m, 4H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.7, 140.0, 139.9, 138.1, 128.9, 128.3, 127.9, 127.7, 127.1, 115.1, 56.7, 37.3, 19.9; HRMS (ESI-TOF) Calcd for C17H20NO2S+ ([M + H]+) 302.1209. Found 302.1212. 1k, N-(4-Bromophenyl)-N-(2-methylallyl)ethanesulfonamide. Yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.37 (t, J = 7.4 Hz, 3H), 1.73 (s, 3H), 3.04 (q, J = 7.4 Hz, 2H), 4.27 (s, 2H), 4.79 (s, 1H), 4.81 (s, 1H), 7.25 (ddd, J = 3.0, 2.1, 8.8 Hz, 2H), 7.49 (ddd, J = 3.0, 2.1, 8.8 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.7, 138.1, 132.4, 129.7, 121.3, 115.4, 57.0, 45.3, 19.8, 8.0; HRMS (ESI-TOF) Calcd for C12H17BrNO2S+ ([M + H]+) 318.0158. Found 318.0159. 1l1, N-(2-Methylallyl)-N-phenylbenzenesulfonamide. White solid; mp 82−83 °C. 1H NMR (400 MHz, CDCl3) δ = 1.76 (s, 3H), 4.11 (s, 2H), 4.71 (s, 1H), 4.75 (s, 1H), 6.99−7.07 (m, 2H), 7.23−7.32 (m, 3H), 7.43−7.48 (m, 2H), 7.55−7.60 (m, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.7, 138.8, 138.2, 132.7, 128.79, 128.78, 128.6, 127.8, 127.7, 115.2, 56.9, 19.9; HRMS (ESI-TOF) Calcd for C16H18NO2S+ ([M + H]+) 288.1053. Found 288.1049. 1l2, N-(2-Methylallyl)-N-(p-tolyl)benzenesulfonamide. Pale yellow solid; mp 89−90 °C. 1H NMR (400 MHz, CDCl3) δ = 1.75 (s, 3H), 2.32 (s, 3H), 4.08 (s, 2H), 4.69−4.71 (m, 1H), 4.74−4.76 (m, 1H), 6.89 (ddd, J = 2.4, 1.9, 8.3 Hz, 2H), 7.05−7.09 (m, 2H), 7.43−7.49 (m, 2H), 7.55−7.61 (m, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.8, 138.2, 137.7, 136.0, 132.6, 129.5, 128.8, 128.3, 127.7, 115.1, 56.9, 21.1, 19.9; HRMS (ESI-TOF) Calcd for C17H20NO2S+ ([M + H]+) 302.1209. Found 302.1210. 1l3, N-(4-Bromophenyl)-N-(2-methylallyl)benzenesulfonamide. White solid; mp 85−86 °C. 1H NMR (400 MHz, CDCl3) δ = 1.73 (s, 3H), 4.07 (s, 2H), 4.70 (s, 1H), 4.76−4.78 (m, 1H), 6.90 (ddd, J = 3.0, 2.1, 8.8 Hz, 2H), 7.40 (ddd, J = 3.0, 2.1, 8.8 Hz, 2H), 7.45−7.51 (m, 2H), 7.57−7.62 (m, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.3, 137.8, 137.7, 132.9, 132.0, 130.1, 129.0, 127.6, 121.6, 115.7, 56.7, 19.8; HRMS (ESI-TOF) Calcd for C16H17BrNO2S+ ([M + H]+) 366.0158. Found 366.0163. 1m, 4-Methyl-N-(2-methylallyl)-N-phenylbenzenesulfonamide. Pale yellow solid; mp 113−114 °C. 1H NMR (400 MHz, CDCl3) δ = 1.75 (s, 3H), 2.42 (s, 3H), 4.09 (s, 2H), 4.70−4.71 (m, 1H), 4.73− 4.75 (m, 1H), 7.00−7.08 (m, 2H), 7.23−7.31 (m, 5H), 7.46 (ddd, J = 1.9, 1.8, 8.3 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 143.4, 139.8, 138.9, 135.2, 129.4, 128.7, 128.6, 127.72, 127.67, 115.1, 56.8, 21.6, 19.9; HRMS (ESI-TOF) Calcd for C17H20NO2S+ ([M + H]+) 302.1209. Found 302.1208. 1n, 2-Methyl-N-(2-methylallyl)-N-(p-tolyl)benzenesulfonamide. White solid; mp 120−121 °C. 1H NMR (400 MHz, CDCl3) δ = 1.74 (s, 3H), 2.30 (s, 3H), 2.31 (s, 3H), 4.16 (s, 2H), 4.71−4.73 (m, 1H), 4.75−4.77 (m, 1H), 6.97 (ddd, J = 2.3, 2.0, 8.4 Hz, 2H), 7.03− 7.07 (m, 2H), 7.22−7.27 (m, 2H), 7.41 (ddd, J = 1.3, 7.5, 7.5 Hz, 1H), 7.79 (dd, J = 1.4, 8.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.0, 138.1, 137.6, 136.8, 135.9, 132.7, 132.5, 130.4, 129.5, 128.4, 126.1, 115.3, 57.1, 21.1, 20.9, 20.0; HRMS (ESI-TOF) Calcd for C18H22NO2S+ ([M + H]+) 316.1366. Found 316.1368. 1o, 4-Bromo-N-(2-methylallyl)-N-phenylbenzenesulfonamide. Yellow solid; mp 81−82 °C 1H NMR (400 MHz, CDCl3) δ = 1.75 (s, 3H), 4.10 (s, 2H), 4.71 (s, 1H), 4.76 (s, 1H), 7.01−7.06 (m, 2H), 7.27−7.32 (m, 3H), 7.43 (ddd, J = 2.3, 2.0, 8.7 Hz, 2H), 7.60 (ddd, J = 2.3, 2.0, 8.7 Hz, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.4, 138.4, 137.1, 132.1, 129.2, 128.9, 128.5, 128.0, 127.7, 115.5, 56.9, 19.9; HRMS (ESI-TOF) Calcd for C16H17BrNO2S+ ([M + H]+) 366.0158. Found 366.0169. 1p, N′-([1,1′-Biphenyl]-4-yl)-N,N-dimethyl-N′-(2-methylallyl)sulphamide. Red solid; mp 106−107 °C. 1H NMR (400 MHz, CDCl3) δ = 1.79 (s, 3H), 2.79 (s, 6H), 4.26 (s, 2H), 4.82 (s, 2H), 7.35 4688


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The Journal of Organic Chemistry (dddd, J = 2.1, 2.1, 7.3, 7.4 Hz, 1H), 7.41−7.46 (m, 4H), 7.56−7.60 (m, 4H); 13C{1H} NMR (100 MHz, CDCl3) δ = 140.3, 140.2, 140.1, 139.4, 128.8, 128.2, 127.62, 127.56, 127.0, 114.9, 58.4, 38.4, 20.1; HRMS (ESI-TOF) Calcd for C18H23N2O2S+ ([M + H]+) 331.1475. Found 331.1473. 1s, N-Methyl-N-(2-methylallyl)aniline. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.69 (s, 3H), 2.91 (s, 3H), 3.76 (s, 2H), 4.77− 4.79 (m, 1H), 4.81−4.84 (m, 1H), 6.65−6.68 (m, 3H), 7.16−7.22 (m, 2H); 13C{1H} NMR (100 MHz, CDCl3) δ = 149.8, 141.6, 129.2, 116.3, 112.1, 110.9, 58.9, 38.3, 20.2; HRMS (ESI-TOF) Calcd for C11H16N+ ([M + H]+) 162.1277. Found 162.1281. 1t, N-(2-Methylallyl)-N-phenylbenzamide. Pale yellow oil. 1H NMR (400 MHz, CDCl3) δ = 1.82 (s, 3H), 4.51 (s, 2H), 4.89−4.92 (m, 2H), 7.01−7.04 (m, 2H), 7.08−7.25 (m, 6H), 7.31−7.34 (m, 2H); 13 C{1H} NMR (100 MHz, CDCl3) δ = 170.4, 143.9, 141.1, 136.1, 129.7, 128.9, 128.8, 127.8, 127.0, 126.4, 112.5, 55.7, 20.5; HRMS (ESITOF) Calcd for C17H18NO+ ([M + H]+) 252.1383. Found 252.1382. 1u, 2,4-Dichloro-N-(2-methylallyl)-N-phenylbenzamide. White semisolid. 1H NMR (400 MHz, CDCl3) δ = 1.86 (s, 3H), 4.51 (s, 2H), 4.84−4.86 (m, 1H), 4.88 (s, 1H), 7.03 (d, J = 1.0 Hz, 2H), 7.07− 7.21 (m, 5H), 7.23 (dd, J = 1.0, 1.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 167.1, 141.6, 140.2, 135.2, 134.9, 131.7, 129.48, 129.47, 129.0, 127.6, 127.4, 126.6, 113.8, 55.1, 20.4; HRMS (ESITOF) Calcd for C17H16Cl2NO+ ([M + H]+) 320.0603. Found 320.0617. 1v, N-(2-Methylallyl)-N-phenylthiophene-2-sulfonamide. White solid; mp 99−100 °C. 1H NMR (400 MHz, CDCl3) δ = 1.77 (s, 3H), 4.16 (s, 2H), 4.75 (s, 1H), 4.76−4.78 (m, 1H), 7.06−7.11 (m, 3H), 7.28−7.34 (m, 4H), 7.59 (dd, J = 1.4, 5.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ = 139.6, 138.5, 138.4, 132.6, 131.9, 128.9, 128.5, 128.0, 127.4, 115.4, 57.1, 19.9; HRMS (ESI-TOF) Calcd for C14H16NO2S2+ ([M + H]+) 294.0617. Found 294.0621.

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ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.joc.8b00450. Spectroscopic data (PDF)

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected], [email protected] ORCID

Deqiang Liang: 0000-0003-0482-0527 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS We gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 21702083). REFERENCES

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Silver-Catalyzed Radical Arylphosphorylation of Unactivated Alkenes

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