Formation

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Cite This: J. Org. Chem. 2018, 83, 8780−8785

Copper-Catalyzed Ring Expansion of Cyclopropyl Ketones/ Formation of N‑acyliminium/Hetero-[4 + 2]-Cycloaddition: A Route to Substituted Pentacyclic Isoindolin-1-one Jian Li,*,† Shuhua Bai,† Yang Li,† Zhengbing Wang,† Xiaoyu Huo,† and Li Liu‡ †

School of Pharmaceutical Engineering & Life Sciences, Changzhou University, Changzhou, 213164, China School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, China

‡

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S Supporting Information *

ABSTRACT: A Cu-catalyzed three-component cascade cyclization among 2-formylbenzonitrile, cyclopropyl ketones, and diaryliodonium salts for the construction of fused isoindolin-1-one compounds is achieved. Pentacyclic isoindolinone derivatives could be obtained in moderate to good yields. The proposed mechanism involved a ring expansion of cyclopropyl ketones/formation of N-acyliminium/hetero-[4 + 2]-cycloaddition process.

T

compared to other d8 species,9 and the species can activate nitriles to give an N-arylnitrilium intermediate by copper catalysis. When the ortho-substituted group of benzonitrile was aldehyde, an interesting reaction happened by the activation of the copper catalyst. The proposed mechanism involved an intermediate N-aryl nitrilium cation, which was a highly reactive species and can easily undergo a coupling reaction forming new C−C bonds simultaneously.10 Two other examples of our group demonstrate this reaction strategy, and 2,3-disubstituted isoindolin-1-ones were synthesized.11 On the other hand, cyclopropanes have attracted much attention as versatile building blocks in organic synthesis due to their remarkable reactivity through ring opening reactions.12 In the case of the compounds having double bonds, such as CO, the η2-coordination between transition metal and ketone could enhance the ring opening reaction, becoming a very powerful method to construct cyclic compounds.13 In one of them, dihydrofurans can be prepared from cyclopropyl ketones via [1,3]-transposition under Lewis acid or transition metal catalysis.14 Inspired by the above study, we questioned if the formation of N-aryl nitrilium cation and the ring-enlargement of cyclopropyl ketones could occur in one pot. To verify this idea, we decided to investigate the cascade reaction with 2formylbenzonitrile, cyclopropyl ketones, and diaryliodonium salts. The proposed sequential transformation involves a threestep catalysis (Scheme 1), where (i) a ring-opening reaction of cyclopropyl ketones 2 is catalyzed by copper salt; (ii) 2formylbenzonitrile 1 is trigged by diaryliodonium salts 3 to afford N-aryl nitrilium cation in the presence of copper catalyst; and (iii) the catalytic sequence is terminated by N-aryl nitrilium cation via hetero-[4 + 2]-cycloaddition reaction,

he isoindolin-1-one structural motif forms the core of many natural products and pharmaceuticals exhibiting important biological activities.1 In particular, ring-fused isoindolin-1-one represents an important class of alkaloids2 and bioactive compounds due to their various medicinal properties (Figure 1), such as PARO-1 inhibitor,3 non-

Figure 1. Examples of biologically active polycyclic isoindolinones.

nucleoside HIV-reverse transcriptase inhibitors,4 anti-Parkinson,5 and vasodilators.6 In view of the structural diversity and the broad range of biological activities, extensive efforts toward those coveted structures synthesis have been made in the past decades.7 However, available methods generally require multistep reactions and are often unsatisfactory in both yield and generality. Thus, it is highly desirable to develop more efficient and convenient methods for the synthesis of polycyclic isoindolin-1-ones. Recently, we developed a tandem annulation synthesizing polysubstituted isoindolin-1-ones from diaryliodonium salts and 2-formylbenzonitrile.8 According Gaunt’s proposal, the process involved a Cu(III)-aryl species, which possesses a d8 configuration and is more electrophilic © 2018 American Chemical Society

Received: May 2, 2018 Published: June 19, 2018 8780

DOI: 10.1021/acs.joc.8b01120 J. Org. Chem. 2018, 83, 8780−8785

Note

The Journal of Organic Chemistry

shortening the time to 30 min, the reaction furnished 4a in 57% yield (Table 1, entry 11). DCE seemed to be the optimal solvent for the three-component cascade cyclization, as it performed in other solvents giving the corresponding product 4a in lower yields (entries 11−15); even in some solvent (CH3CN, 1,4-dioxane, THF, DMF), no desired isoindolin-1one compound was isolated. When the reaction temperature was lowered from 110 to 80 °C or room temperature, the product outcome was effected dramatically resulting in lower yields. In contrast, when the reaction was performed at higher temperature (130 °C), the yield of 4a decreased to 43% after the same time. Reduction of the loadings of Cu(OAc)2 (5 and 1 mol %) resulted in significantly decreased yields (entries 19− 20). Interestingly, the iodonium salts with the Br anion did not afford corresponding product (entry 21). With the optimized conditions in hand, the generality of this cascade reaction was then examined. As summarized in Table 2, the reaction with a series of diaryliodonium salts 3 reacted

Scheme 1. Synthetic Strategies of Pentacyclic Isoindolines

affording fused isoindolin-1-ones in moderate to good yields. The developed methodology provides straightforward access to pentacyclic isoindolin-1-ones derivatives from readily available 2-formylbenzonitrile, cyclopropyl ketones, and diaryliodonium salts in a one-pot reaction. Initially, an investigation of the reaction conditions was conducted by using 2-formylbenzonitrile 1a, 1-cyclopropylethanone 2a, and bis(4-chlorophenyl)iodonium triflate 3a as starting materials. No target compound was observed in dichloromethane (DCM) in the absence of catalyst at 110 °C for 12 h. Generally, under Lewis acid and transition-metal catalysis, chelation to the acyl groups would act to weaken the cyclopropane bond leading to ring opening.15 Therefore, we chose 10 mol % of CuBr2 as the catalyst and DCE as the solvent and were pleased to isolate 4a in 8% yield after 12 h (Table 1, entry 1). Further investigation showed that anhydrous Cu(OAc)2 was a better catalyst than CuBr, Cu(OTf)2, Cu2O, CuI, and [Cu(CH3CN)4]PF6, providing 4a in 51% yield (Table 1, entries 3−9). Remarkably, by

Table 2. Scope of Reaction with Various 2Formylbenzonitrile 1 and Diaryliodonium Salts 3a

Table 1. Optimization of the Reaction Conditionsa

entry

catalyst

solvent

temp (°C)

yield (%)

1 2 3 4 5 6 7 8 9 10b 11c 11 12 13 14 15 16 17 18 19d 20e 21f

− CuBr2 CuBr Cu(OTf)2 Cu2O CuI CuCl Cu(OAc)2 [Cu(CH3CN)4]PF6 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2 Cu(OAc)2

DCE DCE DCE DCE DCE DCE DCE DCE DCE DCE DCE CH3CN 1,4-dioxane toluene THF DMF DCE DCE DCE DCE DCE DCE

110 110 110 110 110 110 110 110 110 110 110 110 110 110 110 110 r.t 80 130 110 110 110

− 8 33 31 15 4 14 51 17 55 57 − − 27 − − − 19 43 42 11 −

a

Reaction conditions: 1a (0.3 mmol), 2a (0.6 mmol), 3a (0.36 mmol), and Cu(OAc)2 (10 mol %) in DCE (2.0 mL), 110 °C, 30 min.

smoothly with 2-formylbenzonitrile 1a and 1-cyclopropylethanone 2a to generate the expected fused ring derivatives in moderate yields with excellent chemoselectivity. The reaction works well with the symmetric (3a−e) and unsymmetric (3f, 3g) diaryliodonium salts. As can be seen from Table 2, the reactivity of the salts can be increased by installation of an electron-donating group, such as methyl and methoxy at the para-position, and the salt with a halogen group became sluggish (4a, 4c, and 4f). Even the meta-substrate 3e can

a

Reaction conditions: 1a (0.3 mmol), 2a (0.6 mmol), 3a (0.36 mmol), and catalyst (10 mol %) in DCE (2.0 mL), 110 °C, 12 h. b2 h. c 30 min. dCatalyst (5 mol %). eCatalyst (1 mol %). fDiphenyliodonium bromide was used instead of 3a. 8781

DOI: 10.1021/acs.joc.8b01120 J. Org. Chem. 2018, 83, 8780−8785

Note

The Journal of Organic Chemistry

The steric structure of the products obtained from the aryl cyclopropyl ketones are different from alkyl cyclopropyl ketones, which may be due to steric hindrance effects. To gain insight into the mechanism of this cascade reaction, several control experiments were performed (Scheme 2). First,

produce the target compound 4e in 68% yield smoothly. Of note is that reactions with unsymmetrical diaryliodonium reagents are more suitable for this transformation compared with symmetric substrates. This is likely due to the nontransferable aryl ring being mesitylene resulting in the socalled “anti-ortho” effect,16 which governs chemoselectivity. To our delight, a variety of 2-formylbenzonitriles 1 containing varying electronic nature at the 4- and 5-positions afforded 4 in moderate to good yields. When the substituent group at the 4position was Br, the yield of 4j was up to 83%. The structure of 4i was confirmed by X-ray crystallographic analysis. The successful reaction of ring enlargement/cycloaddition with 1-cyclopropylethanone prompted us to investigate its reaction with arylcarbonylcyclopropane. The substrate scope of the reaction was examined (Table 3). To our delight, various

Scheme 2. Experiments for Mechanistic Understanding

Table 3. Scope of Cyclopropyl Ketonesa

2 equiv of 5-methyl-2,3-dihydrofuran 5 were used instead of 1cyclopropylethanone 2a, and a 49% yield of 4c was obtained under the standard conditions, which suggested that the ring enlargement of 1-cyclopropylethanone might occur via the catalyst activation. Next, after treatment of 5-methyl-2,3dihydrofuran 5 with 3-hydroxy-2-phenylisoindolin-1-one 6,18 which was used as the N-acyliminium ion precursor, a 61% yield of 4b was successfully assembled under the promotion of Cu(OAc)2. This demonstrates that the mechanism of this onepot reaction involved the formation of the N-acyliminium ion and hetero-[4 + 2]-cycloaddition process. Based on the above control experimental results, we proposed the mechanism shown in Figure 2. Initially, the 2-

Figure 2. Proposed reaction mechanism.

formylbenzonitrile 1 is subjected to a reaction with diaryliodonium salts 3 to provide N-aryl nitrilium cation A in the presence of a copper catalyst,19 followed by an intramolecular cyclization reaction to produce intermediate B. On the other hand, ring enlargement of cyclopropyl ketones 2 occurs catalyzed by the copper salts to give dihydrofuran derivatives C simultaneously.20 Then, the hetero-[4 + 2] cycloaddition occurs between the intermediate B and dihydrofuran C to generate intermediate E. Finally, the deprotonation of the intermediate E affords the final product isoindolinone 4. In conclusion, we have developed a copper-catalyzed cascade reaction of 2-formylbenzonitrile, cyclopropyl ketones, and diaryliodonium salts via a ring expansion of cyclopropyl ketones/formation of N-acyliminium/hetero-[4 + 2]-cycloaddition process. The developed methodology afforded an approach for the construction of a biologically important

a

Reaction conditions: 1a (0.3 mmol), 2a (0.6 mmol), 3a (0.36 mmol), and catalyst (10 mol %) in DCE (2.0 mL), 110 °C, 30 min.

arylcarbonylcyclopropanes 2 bearing either electron-donating groups (e.g., methyl and ethyl) or electron-withdrawing groups (e.g., ethyl formate and trifluoromethyl) on the phenyl rings were all smoothly transformed under the standard conditions to give the desired products 4aa−4ah in moderate to good yields. The results indicated that electron-donating substrates (2c, 2e) are more suitable for this reaction than the electronwithdrawing substrates (2h, 2i). The steric hindrance effect17 of cyclopropyl ketones 2 was not observed in the reaction of cyclopropyl(o-tolyl)methanone 2d with other substrates, which generated 4ac in 68% yield. Meanwhile, the structures of 4ab and 4af were confirmed by X-ray crystallographic diffraction. 8782

DOI: 10.1021/acs.joc.8b01120 J. Org. Chem. 2018, 83, 8780−8785

Note

The Journal of Organic Chemistry

3H), 1.58−1.55 (m, 1H), 1.22−1.20 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 166.7, 143.3, 138.4, 134.7, 133.1, 132.3, 128.8, 127.6, 125.9, 124.4, 121.6, 119.8, 80.1, 65.0, 58.2, 47.1, 28.8, 24.4, 21.5. HRMS (ESI): calcd for C20H20NO2 ([M + H]+) 306.1489; found 306.1493. Compound 4f. White solid (58.4 mg, 63%). Mp: 117−121 °C. 1H NMR (400 MHz, CDCl3) δ 8.48 (q, J = 5.2 Hz, 1H), 7.96 (d, J = 7.5 Hz, 1H), 7.65 (t, J = 7.4 Hz, 1H), 7.58−7.53 (m, 2H), 7.27−7.25 (m, 1H), 7.07 (dt, J = 8.2, 2.8 Hz, 1H), 5.05 (d, J = 2.9 Hz, 1H), 3.79 (q, J = 6.8 Hz, 1H), 3.46−3.43 (m, 1H), 2.83 (dt, J = 9.5, 3.0 Hz, 1H), 1.80 (s, 3H), 1.58−1.55 (m, 1H), 1.21−1.14 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 166.6, 159.7 (d, J = 246.2 Hz), 143.0, 132.8 (d, J = 6.4 Hz), 132.7, 130.8, 128.9, 124.4, 121.6, 121.2 (d, J = 7.8 Hz), 115.4 (d, J = 22.3 Hz), 114.2, 114.0, 80.1, 65.3, 57.9, 46.8, 28.6, 24.2. 19 F NMR (282 MHz, CDCl3) δ −116.7. HRMS (ESI): calcd for C19H17FNO2 ([M + H]+) 310.1238; found 310.1233. Compound 4g. White solid (66.5 mg, 69%). Mp: 190−193 °C. 1H NMR (400 MHz, CDCl3) δ 8.42 (d, J = 9.0 Hz, 1H), 7.95 (d, J = 7.5 Hz, 1H), 7.65−7.61 (m, 1H), 7.56−7.51 (m, 2H), 7.09 (d, J = 2.9 Hz, 1H), 6.94 (dd, J = 9.0 2.9 Hz, 1H), 5.02 (d, J = 3.0 Hz, 1H), 3.85 (s, 3H), 3.81−3.76 (m, 1H), 3.48−3.42 (m, 1H), 2.83 (dd, J = 9.5, 3.1 Hz, 1H), 1.81 (s, 1H), 1.61−1.52 (m, 3H), 1.23−1.18 (m, 1H). 13 C{1H} NMR (125 MHz, CDCl3) δ 166.4, 156.7, 143.1, 133.2, 132.1, 132.0, 128.7, 124.2, 121.6, 120.8, 114.5, 112.2, 80.3, 65.2, 57.9, 55.5, 47.1, 28.7, 24.3. HRMS (ESI): calcd for C20H20NO3 ([M + H]+) 322.1438; found 322.1432. Compound 4h. White solid (77.8 mg, 65%). Mp: 165−167 °C. 1H NMR (400 MHz, CDCl3) δ 8.37 (d, J = 8.7 Hz, 1H), 7.85 (d, J = 8.5 Hz, 1H), 7.67−7.68 (m, 1H), 7.45 (dd, J = 8.8, 1.6 Hz, 1H), 7.08− 7.05 (m, 1H), 6.99 (br, 1H), 4.98 (d, J = 1.5 Hz, 1H), 3.94 (s, 3H), 3.81 (q, J = 8.4 Hz, 1H), 3.49−3.44 (m, 1H), 2.77 (dt, J = 9.4, 3.0 Hz, 1H), 1.79 (s, 3H), 1.64−1.57 (m, 1H), 1.27−1.24 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 166.6, 163.7, 145.4, 137.9, 132.5, 131.4, 1307, 125.9, 125.1, 121.0, 117.4, 115.5, 106.4, 80.0, 65.3, 57.5, 55.8, 46.8, 28.6, 24.2. HRMS (ESI): calcd for C20H19BrNO3 ([M + H]+) 400.0543; found 400.0538. Compound 4i. White solid (87.0 mg, 72%). Mp: 249−251 °C. 1H NMR (400 MHz, CDCl3) δ 8.37 (d, J = 8.8 Hz, 1H), 7.89 (d, J = 8.7 Hz, 1H), 7.70−7.69 (m, 1H), 7.54−7.53 (m, 2H), 7.47 (dd, J = 8.8, 2.2 Hz, 1H), 5.03 (d, J = 2.8 Hz, 1H), 3.82 (q, J = 8.5 Hz, 1H), 3.50− 3.44 (m, 1H), 2.79 (dt, J = 9.5, 3.0 Hz, 1H), 1.79 (s, 3H), 1.68−1.63 (m, 1H), 1.19−1.15 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.6, 144.6, 139.1, 133.4, 132.7, 131.5, 131.1, 130.8, 129.7, 125.7, 122.2, 121.1, 118.0, 79.9, 65.3, 57.5, 46.6, 28.6, 24.2. HRMS (ESI): calcd for C19H16BrClNO2 ([M + H]+) 404.0047; found 404.0042. Compound 4j. White solid (111.0 mg, 83%). Mp: 251−254 °C. 1H NMR (400 MHz, CDCl3) δ 8.36 (d, J = 8.8 Hz, 1H), 7.83 (d, J = 8.0 Hz, 1H), 7.71−7.69 (m, 3H), 7.47 (dd, J = 8.8, 2.4 Hz, 1H), 5.03 (d, J = 3.2 Hz, 1H), 3.85−3.79 (m, 1H), 3.50−3.44 (m, 1H), 2.79 (dt, J = 9.4, 3.0 Hz, 1H), 1.79 (s, 3H), 1.68−1.63 (m, 1H), 1.22−1.15 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.6, 144.7, 133.3, 132.6, 132.4, 131.5, 131.4, 130.7, 127.3, 125.8, 125.0, 120.9, 117.9, 79.8, 65.1, 57.3, 46.5, 28.5, 24.0. HRMS (ESI): calcd for C19H16Br2NO2 ([M + H]+) 447.9542; found 447.9537. Compound 4aa. White solid (68.5 mg, 53%). Mp: 194−196 °C. 1 H NMR (400 MHz, CDCl3) δ 8.28 (d, J = 8.8 Hz, 1H), 8.03 (d, J = 6.8 Hz, 1H), 7.67−7.57 (m, 3H), 7.45 (dd, J = 8.8, 2.8 Hz, 1H), 7.32−7.24 (m, 5H), 7.20 (d, J = 2.2 Hz, 1H), 4.63 (d, J = 11.6 Hz, 1H), 4.35−4.31 (m, 2H), 2.65 (dd, J = 11.4, 6.7 Hz, 1H), 2.57−2.51 (m, 1H), 2.31−2.23 (m, 1H). 13C NMR (100 MHz, CDCl3) δ 165.4, 144.6, 143.6, 133.2, 133.1, 132.9, 132.6, 132.3, 131.5, 128.9, 128.4, 127.2, 125.3, 124.7, 122.6, 121.9, 117.6, 85.5, 65.5, 58.4, 50.9, 27.8. HRMS (ESI): calcd for C24H19BrNO2 ([M + H]+) 432.0594; found 432.0600. Compound 4aa′. White solid (79.0 mg, 71%). Mp: 218−219 °C. 1 H NMR (400 MHz, CDCl3) δ 8.36 (dd, J = 9.1, 5.2 Hz, 1H), 8.04− 8.03 (m, 1H), 7.67−7.59 (m, 3H), 7.32−7.27 (m, 2H), 7.25−7.23 (m, 3H), 7.08−7.03 (m, 1H), 6.78 (dd, J = 9.2, 3.0 Hz, 1H), 4.64 (d, J = 11.5 Hz, 1H), 4.37 (dd, J = 9.4, 5.4 Hz, 2H), 2.68−2.64 (m, 1H),

pentacyclic isoindolin-1-one skeleton. Further research to explore the possibility for synthesis of complicated fused isoindolinones is ongoing in our laboratory.

■

EXPERIMENTAL SECTION

General Information. All reactions were carried out under an air atmosphere. Various reagents were purchased from Aldrich, Acros, or Alfa. 2-Formylbenzonitrile 1, arylcarbonylcyclopropane 2, and diaryliodonium salts 3 were prepared according to literature. Flash column chromatography was performed using silica gel (200−300 mesh). NMR spectra were recorded in CDCl3 on a Bruker NMR-400 (400 MHz) and NMR-500 (500 MHz) with TMS as an internal reference. HRMS was performed utilizing an Agilent 6540 Q-TOF mass spectrometer (ESI). X-ray crystallographic data were collected using a SMART APEX II X-ray diffractometer. Melting points were determined on an SGW X-4B melting point apparatus. General Procedure for Preparation of Compound 4. A solution of 2-formylbenzonitrile 1 (0.3 mmol), cyclopropyl ketones 2 (0.6 mmol), diaryliodonium salt 3 (0.36 mmol), and Cu(OAc)2 (0.03 mmol, 5.5 mg, 10 mol %) in DCE (2 mL) was stirred at 110 °C for 30 min. After completion of the reaction (observed on TLC), the solvent was evaporated and the residues was purified by silica-gel column chromatography (Ethyl acetate/Petroleum ether = 1/4−1/2) to afford the pure product 4. The obtained product was analyzed by 1H NMR, 13C NMR, and HRMS. Compound 4a. White solid (55.6 mg, 57%). Mp: 166−168 °C. 1H NMR (400 MHz, CDCl3) δ 8.45 (d, J = 8.8 Hz, 1H), 7.95 (d, J = 7.5 Hz, 1H), 7.65 (dt, J = 7.4, 1.2 Hz, 1H), 7.57−7.51 (m, 3H), 7.31 (dd, J = 8.8, 2.5 Hz, 1H), 5.03 (d, J = 3.1 Hz, 1H), 3.83−3.75 (m, 1H), 3.48−3.41 (m, 1H), 2.82 (dt, J = 9.5, 3.0 Hz, 1H), 1.79 (s, 3H), 1.58−1.51 (m, 1H), 1.21−1.14 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 166.7, 143.0, 133.2, 132.7, 132.5, 130.0, 128.9, 128.5, 127.8, 124.5, 121.7, 120.8, 80.0, 65.3, 57.9, 46.7, 29.7, 28.6, 24.2. HRMS (ESI): calcd for C19H17ClNO2 ([M + H]+) 326.0942; found 326.0937. Compound 4b. White solid (45.4 mg, 52%). Mp: 149−152 °C. 1H NMR (400 MHz, CDCl3) δ 8.47 (dd, J = 8.3, 1.5 Hz, 1H), 7.97−7.95 (m, 1H), 7.66−7.63 (m, 1H), 7.58−7.51 (m, 3H), 7.36 (dt, J = 8.4, 2.0 Hz, 1H), 7.20 (dt, J = 7.5, 1.2 Hz, 1H), 5.05 (d, J = 3.0 Hz, 1H), 3.82−3.74 (m, 1H), 3.49−3.38 (m, 1H), 2.82 (dt, J = 9.5, 3.0 Hz, 1H), 1.81 (s, 3H), 1.58−1.51 (m, 1H), 1.20−1.14 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 166.7, 143.3, 134.7, 133.0, 132.4, 130.5, 128.8, 128.4, 127.8, 124.9, 124.4, 121.6, 119.5, 80.2, 65.1, 58.0, 47.0, 28.8, 24.3. HRMS (ESI): calcd for C19H18NO2 ([M + H]+) 292.1332; found 292.1327. Compound 4c. White solid (60.8 mg, 55%). Mp: 116−117 °C. 1H NMR (400 MHz, CDCl3) δ 8.38 (d, J = 8.7 Hz, 1H), 7.94 (d, J = 7.4 Hz, 1H), 7.68−7.62 (m, 2H), 7.54 (t, J = 8.7 Hz, 2H), 7.44 (dd, J = 8.9, 2.4 Hz, 1H), 5.04 (d, J = 3.1 Hz, 1H), 3.82−3.75 (m, 1H), 3.48− 3.40 (m, 1H), 2.82 (dt, J = 9.5, 3.0 Hz, 1H), 1.79 (s, 3H), 1.62−1.51 (m, 1H), 1.27−1.14 (m, 1H). 13C{1H}NMR (125 MHz, CDCl3) δ 166.7, 143.1, 133.7, 132.6, 131.4, 130.7, 128.9, 124.4, 121.7, 121.1, 117.7, 79.9, 65.3, 57.8, 46.7, 28.6, 24.2. HRMS (ESI): calcd for C19H17BrNO2 ([M + H]+) 370.0437; found 370.0435. Compound 4d. White solid (59.4 mg, 65%). Mp: 84−86 °C. 1H NMR (400 MHz, CDCl3) δ 8.37 (d, J = 8.4 Hz, 1H), 7.96 (d, J = 7.5 Hz, 1H), 7.64 (t, J = 7.1 Hz, 1H), 7.56−7.52 (m, 2H), 7.38 (s, 1H), 7.20−7.17 (m, 1H), 5.02 (d, J = 2.8 Hz, 1H), 3.77 (dd, J = 15.0, 8.5 Hz, 1H), 3.46−3.40 (m, 1H), 2.81 (dt, J = 9.5, 3.0 Hz, 1H), 2.36 (s, 3H), 1.80 (s, 3H), 1.58−1.54 (m, 1H), 1.25−1.20 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 166.5, 143.2, 134.5, 133.1, 132.3, 132.2, 130.3, 129.2, 128.7, 128.0, 124.3, 121.6, 119.3, 80.2, 65.1, 58.0, 47.1, 29.7, 28.7, 24.3, 21.1. HRMS (ESI): calcd for C20H20NO2 ([M + H]+) 306.1489; found 306.1494. Compound 4e. White solid (62.2 mg, 68%). Mp: 154−159 °C. 1H NMR (400 MHz, CDCl3) δ 8.33 (s, 1H), 7.97 (d, J = 7.5 Hz, 1H), 7.64 (t, J = 7.4 Hz, 1H), 7.57−7.52 (m, 2H), 7.46 (d, J = 8.0 Hz, 1H), 7.04 (d, J = 8.0 Hz, 1H), 5.04 (d, J = 3.0 Hz, 1H), 3.80−3.77 (m, 1H), 3.45−3.49 (m, 1H), 2.85−2.80 (m, 1H), 2.42 (s, 3H), 1.81 (s, 8783

DOI: 10.1021/acs.joc.8b01120 J. Org. Chem. 2018, 83, 8780−8785

Note

The Journal of Organic Chemistry

Compound 4ag. White solid (89.0 mg, 59%). Mp: 221−224 °C. H NMR (400 MHz, CDCl3) δ 8.29 (d, J = 8.8 Hz, 1H), 8.04 (d, J = 7.0 Hz, 1H), 7.98 (d, J = 8.4 Hz, 2H),7.65−7.59 (m, 3H), 7.47 (dd, J = 8.8, 2.2 Hz, 1H), 7.33 (d, J = 8.4 Hz, 2H), 7.16 (d, J = 2.2 Hz, 1H), 4.65 (d, J = 11.6 Hz, 1H), 4.39−4.33 (m, 4H), 2.67−2.55 (m, 2H), 2.26−2.22 (m, 1H), 1.38 (t, J = 7.1 Hz, 3H). 13C{1H} NMR (100 MHz, CDCl3) δ 166.2, 165.5, 149.8, 143.5, 133.2, 132.6, 132.5, 132.4, 131.9, 129.8, 129.7, 129.2, 125.5, 124.9, 122.7, 122.1, 117.8, 85.6, 65.7, 61.0, 58.3, 50.9, 27.9, 14.3. HRMS (ESI): calcd for C27H23BrNO4 ([M + H]+) 504.0805; found 504.0799. Compound 4ah. White solid (94.3 mg, 63%). Mp: 230−232 °C. 1 H NMR (400 MHz, CDCl3) δ 8.29 (d, J = 8.8 Hz, 1H), 8.04 (d, J = 6.9 Hz, 1H), 7.66−7.60 (m, 3H), 7.58−7.56 (m, 2H), 7.48 (dd, J = 8.8, 2.3 Hz, 1H), 7.38 (d, J = 8.2 Hz, 2H), 7.15 (d, J = 2.2 Hz, 1H), 4.63 (d, J = 11.5 Hz, 1H), 4.35 (dd, J = 9.5, 5.1 Hz, 2H), 2.65−2.56 (m, 2H), 2.26−2.23 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.6, 149.2, 143.5, 133.3, 133.2, 132.7, 132.4, 132.1, 129.3, 125.9, 125.6, 124.9, 122.8, 122.3, 117.9, 85.5, 65.9, 58.4, 51.3, 28.0. 19F NMR (376 MHz, CDCl3) δ −62.5. HRMS (ESI): calcd for C25H18BrF3NO2 ([M + H]+) 500.0468; found 500.0473.

2.57−2.54 (m, 1H), 2.32−2.22 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.4, 159.4 (d, J = 243.0 Hz), 144.9, 143.7, 133.1 (d, J = 7.5 Hz), 130.2, 129.0,128.4, 127.3, 125.4, 124.7, 122.6, 122.1 (d, J = 8.2 Hz), 116.9 (d, J = 22.6 Hz), 115.8 (d, J = 22.6 Hz), 85.7, 65.6, 58.6, 50.9, 27.9. 19F NMR (376 MHz, CDCl3) δ −116.4. HRMS (ESI): calcd for C24H19FNO2 ([M + H]+) 372.1394; found 372.1389. Compound 4ab. White solid (105.4 mg, 79%). Mp: 189−192 °C. 1 H NMR (400 MHz, CDCl3) δ 8.27 (d, J = 8.8 Hz, 1H), 8.02 (d, J = 7.1 Hz, 1H), 7.67−7.57 (m, 3H), 7.44 (dd, J = 8.8, 2.3 Hz, 1H), 7.21 (d, J = 2.2 Hz, 1H), 7.12 (dd, J = 13.2, 8.3 Hz, 4H), 4.62 (d, J = 11.6 Hz, 1H), 4.31 (dd, J = 9.3, 5.4 Hz, 2H), 2.62 (dd, J = 11.5, 6.7 Hz, 1H), 2.54−2.51 (m, 1H), 2.32 (s, 3H), 2.28−2.20 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.5, 143.7, 141.7, 137.0, 133.3, 133.2, 133.1, 132.7, 132.4, 131.6, 129.2, 129.0, 125.4, 124.8, 122.7, 122.0, 117.7, 85.5, 65.5, 58.5, 50.9, 27.9, 21.0. HRMS (ESI): calcd for C25H21BrNO2 ([M + H]+) 446.0750; found 446.0748. Compound 4ac. White solid (90.8 mg, 68%). Mp: 246−248 °C. 1 H NMR (400 MHz, CDCl3) δ 8.26 (d, J = 8.8 Hz, 1H), 8.04 (d, J = 7.0 Hz, 1H), 7.78 (d, J = 7.6 Hz, 1H), 7.67−7.59 (m, 3H), 7.49 (dd, J = 8.8, 2.3 Hz, 1H), 7.32−7.78 (m, 1H), 7.20 (t, J = 7.4 Hz, 1H), 7.14 (d, J = 2.2 Hz, 1H), 7.00 (d, J = 7.4 Hz, 1H), 4.67 (d, J = 11.6 Hz, 1H), 4.46−4.41 (m, 1H), 4.37−4.31 (m, 1H), 2.64−2.60 (m, 1H), 2.58−2.53 (m, 1H), 2.23−2.19 (m, 1H), 1.67 (s, 3H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.5, 143.8, 142.1, 133.7, 133.5, 132.5, 132.4, 131.6, 129.1, 127.9, 125.8, 125.6, 124.9, 122.8, 122.8, 122.0, 117.8, 85.5, 65.3, 57.8, 47.7, 27.9, 20.2. HRMS (ESI): calcd for C25H21BrNO2 ([M + H]+) 446.0750; found 446.0745. Compound 4ad. White solid (111.5 mg, 81%). Mp: 187−189 °C. 1 H NMR (400 MHz, CDCl3) δ 8.27 (d, J = 8.8 Hz, 1H), 8.03 (d, J = 6.8 Hz, 1H), 7.63−7.58 (m, 3H), 7.45 (dd, J = 8.8, 2.3 Hz, 1H), 7.22 (d, J = 2.3 Hz, 1H), 7.14 (dd, J = 12.6, 8.5 Hz, 4H), 4.63 (d, J = 11.6 Hz, 1H), 4.33−4.30 (m, 2H), 2.65−2.59 (m, 3H), 2.54−2.51 (m, 1H), 2.29−2.28 (m, 1H), 1.22 (t, J = 7.6 Hz, 3H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.5, 143.7, 143.3, 131.9, 133.3, 133.2, 132.7, 131.6, 129.0, 127.9, 125.4, 124.8, 122.7, 122.0, 117.8, 85.5, 65.5, 58.5, 50.9, 28.4, 27.9, 15.3. HRMS (ESI): calcd for C26H23BrNO2 ([M + H]+) 460.0907; found 460.0902. Compound 4ad′. White solid (94.5 mg, 79%). Mp: 173−175 °C. 1 H NMR (400 MHz, CDCl3) δ 8.35 (dd, J = 9.0, 5.2 Hz, 1H), 8.04− 8.02 (m, 1H), 7.67−7.56 (m, 3H), 7.17−7.11 (m, 4H), 7.07−7.02 (m, 1H), 6.80 (dd, J = 9.3, 3.0 Hz, 1H), 4.64 (d, J = 11.5 Hz, 1H), 4.31 (dd, J = 9.3, 5.4 Hz, 2H), 2.67−2.59 (m, 3H), 2.57−2.50 (m, 1H), 2.33−2.28 (m, 1H), 1.31 (t, J = 7.6 Hz, 3H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.4, 159.4 (d, J = 242.9 Hz), 143.7, 143.3, 142.0, 133.2 (d, J = 7.0 Hz), 132.8, 132.2, 130.9, 128.9, 127.8, 125.3, 124.7, 122.1 (d, J = 7.8 Hz), 116.8 (d, J = 22.6 Hz), 115.7 (d, J = 22.6 Hz),85.7, 65.5, 58.7, 50.9, 28.4, 28.0, 15.4. 19F NMR (376 MHz, CDCl3) δ −116.4. HRMS (ESI): calcd for C26H23FNO2 ([M + H]+) 400.1707; found 400.1722. Compound 4ae. White solid (87.5 mg, 65%). Mp: 174−178 °C. 1 H NMR (400 MHz, CDCl3) δ 8.27 (d, J = 8.8 Hz, 1H), 8.02 (d, J = 7.0 Hz, 1H), 7.67−7.57 (m, 3H), 7.45 (dd, J = 8.8, 2.3 Hz, 1H), 7.24−7.20 (m, 2H), 7.17 (d, J = 2.2 Hz, 1H), 6.99 (t, J = 8.6 Hz, 2H), 4.63 (d, J = 11.6 Hz, 1H), 4.32 (dd, J = 9.5, 5.2 Hz, 2H), 2.62−2.54 (m, 2H), 2.27−2.20 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.5, 162.2 (d, J = 244.9 Hz), 143.6, 140.6, 133.3, 132.7 (d, J = 21.2 Hz), 132.5, 131.7, 129.2, 127.2 (d, J = 8.0 Hz), 124.8, 122.7, 122.1, 117.7, 115.4 (d, J = 21.3 Hz), 85.3, 65.6, 58.4, 51.1, 27.8. 19F NMR (376 MHz, CDCl 3 ) δ −115.1. HRMS (ESI): calcd for C24H18BrFNO2 ([M + H]+) 450.0499; found 450.0494. Compound 4af. White solid (126.4 mg, 83%). Mp: 263−266 °C. 1 H NMR (400 MHz, CDCl3) δ 8.27 (d, J = 8.8 Hz, 1H), 8.03 (d, J = 7.2 Hz, 1H), 7.65−7.60 (m, 3H), 7.48−7.42 (m, 3H), 7.17−7.12 (m, 3H), 4.62 (d, J = 11.6 Hz, 1H), 4.34−4.30 (m, 2H), 2.61−2.54 (m, 2H), 2.29−2.19 (m, 1H). 13C{1H} NMR (125 MHz, CDCl3) δ 165.5, 144.0, 143.5, 133.2, 131.8, 131.6, 129.1, 127.3, 124.9, 122.7, 122.1, 121.4, 117.8, 85.3, 65.7, 58.3, 50.9, 27.9. HRMS (ESI): calcd for C24H18Br2NO2 ([M + H]+) 509.9699; found 509.9692.

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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.8b01120. Copies of the 1H and 13C NMR spectra for all new products and crystal data (PDF) Single-crystal X-ray data for 4af (CCDC no. 1834907) (CIF) Single-crystal X-ray data for 4ab (CCDC no. 1834909) (CIF) Single-crystal X-ray data for 4i (CCDC no. 1834908) (CIF) Accession Codes

CCDC 1834907−1834909 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_ request/cif, or by emailing [email protected], or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: + 44 1223 336033.

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Jian Li: 0000-0001-6713-1302 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS We are grateful to National Natural Science Foundation of China (21402013), the Natural Science Foundation of Jiangsu Province (BK20140259), Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology (BM2012110) and Advanced Catalysis and Green Manufacturing Collaborative Innovation Center.

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REFERENCES

(1) (a) Larock, R. C. Comprehensive Organic Transformations; VCH: New York, 1989; pp 819−829. (b) Li, E.; Jiang, L.; Guo, L.; Zhang, H.; Che, Y. Pestalachlorides A−C, antifungal metabolites from the plant endophytic fungus Pestalotiopsis adusta. Bioorg. Med. Chem. 8784

DOI: 10.1021/acs.joc.8b01120 J. Org. Chem. 2018, 83, 8780−8785

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The Journal of Organic Chemistry 2008, 16, 7894−7899. (c) Lawson, E. C.; Luci, D. K.; Ghosh, S.; Kinney, W. A.; Reynolds, C. H.; Qi, J.; Smith, C. E.; Wang, Y.; Minor, L. K.; Haertlein, B. J.; Parry, T. J.; Damiano, B. P.; Maryanoff, B. Nonpeptide Urotensin-II Receptor Antagonists: A New Ligand Class Based on Piperazino-Phthalimide and Piperazino-Isoindolinone Subunits. J. Med. Chem. 2009, 52, 7432−7445. (d) Fleming, F. F.; Yao, L.; Ravikumar, P. C.; Funk, L.; Shook, B. C. Nitrile-Containing Pharmaceuticals: Efficacious Roles of the Nitrile Pharmacophore. J. Med. Chem. 2010, 53, 7902−7917. (2) Bentley, K. W. In The Isoquinoline Alkaloids; Ravindranath, B., Ed.; Harwood Academic: Amsterdam, 1998; pp 361−375. (3) Suyavaran, A.; Ramamurthy, C.; Mareeswaran, R.; Shanthi, Y. V.; Selvakumar, J.; Mangalaraj, S.; Kumar, M. S.; Ramanathan, C. R.; Thirunavukkarasu, C. Synthesis and biological evaluation of isoindoloisoquinolinone, pyroloisoquinolinone and benzoquinazolinone derivatives as poly (ADP-ribose) polymerase-1 inhibitors. Bioorg. Med. Chem. 2015, 23, 488−498. (4) Mertens, A.; Zilch, H.; Konig, B.; Schafer, W.; Poll, T.; Kampe, W.; Seidel, H.; Leser, U.; Leinert, H. Selective non-nucleoside HIV-1 reverse transcriptase inhibitors. New 2,3-dihydrothiazolo[2,3-a]isoindol-5(9bH)-ones and related compounds with anti-HIV-1 activity. J. Med. Chem. 1993, 36, 2526−2535. (5) Chen, Z.-L.; Zhu, D.-Y. In The Alkaloids: Chemistry and Pharmacology; Brossi, A., Ed.; Academic Press: New York, 1987; Vol. 31, pp 29−62. (6) Kato, Y.; Takemoto, M.; Achiwa, K. Synthesis of Isoindo-linone Derivatives Possessing Inhibitory Activity for Thromboxane A2 Analog (U-46619)-Induced Vasoconstriction. Chem. Pharm. Bull. 1993, 41, 2003−2006. (7) Boltukhina, E. V.; Zubkov, F. I.; Varlamov, A. V. Methods for the construction of [1,2]isoindolo-condensed benzazepines, benzazocines, quinolines,and isoquinolines-1- isoindolobenzazepines, isoindolobenzazocines. Chem. Heterocycl. Compd. 2006, 42, 971−1001. (8) Liu, L.; Qiang, J.; Bai, S.; Sung, H.-L.; Miao, C.; Li, J. Direct Access to Isoindolin-1-one Scaffolds by Copper-Catalyzed Divergent Cyclizations of 2-Formylbenzonitrile and Diaryliodonium Salts. Adv. Synth. Catal. 2017, 359, 1283−1289. (9) (a) Phipps, R. J.; Grimster, N. P.; Gaunt, M. J. Cu(II)-Catalyzed Direct and Site-Selective Arylation of Indoles Under Mild Conditions. J. Am. Chem. Soc. 2008, 130, 8172−8174. (b) Phipps, R. J.; Gaunt, M. J. A Meta-Selective Copper-Catalyzed C−H Bond Arylation. Science 2009, 323, 1593−1597. (10) (a) Pang, X.; Chen, C.; Su, X.; Li, M.; Wen, L. Diverse Tandem Cyclization Reactions of o-Cyanoanilines and Diaryliodonium Salts with Copper Catalyst for the Construction of Quinazolinimine and Acridine Scaffolds. Org. Lett. 2014, 16, 6228−6231. (b) Peng, J.; Chen, C.; Chen, J.; Su, X.; Xi, C.; Chen, H. Cu-Catalyzed Arylcarbocyclization of Alkynes with Diaryliodonium Salts through C−C Bond Formation on Inert C(sp3)−H Bond. Org. Lett. 2014, 16, 3776−3779. (c) Chen, J.; Chen, C.; Chen, J.; Wang, G.; Qu, H. Cucatalyzed intramolecular aryl-etherification reactions of alkoxyl alkynes with diaryliodonium salts via cleavage of a stable C−O bond. Chem. Commun. 2015, 51, 1356−1359. (d) Wang, G.; Chen, C.; Peng, J. Copper-catalyzed intramolecular aryl-bicyclization of diynes with diaryliodonium salts via vinyl cations. Chem. Commun. 2016, 52, 10277−10280. (11) (a) Liu, L.; Bai, S.; Li, Y.; Wang, L.-X.; Hu, Y.; Sung, H.-L.; Li, J. Synthesis of 2,3-Diarylisoindolin-1-one by Copper-Catalyzed Cascade Annulation of 2-Formylbenzonitriles, Arenes, and Diaryliodonium Salts. J. Org. Chem. 2017, 82, 11084−11090. (b) Liu, L.; Bai, S.; Li, Y.; Ding, X.; Liu, Q.; Li, J. A Three-component Cascade Cyclization to Construct 3-(2-Oxopropyl)-2-arylisoindolinone Derivatives via Copper-catalyzed Annulation. Adv. Synth. Catal. 2018, 360, 1617−1621. (12) For selected reviews, see: (a) Grover, H. K.; Emmett, M. R.; Kerr, M. A. Carbocycles from donor-acceptor cyclopropanes. Org. Biomol. Chem. 2015, 13, 655−671. (b) Schneider, T. F.; Kaschel, J.; Werz, D. B. A New Golden Age for Donor−Acceptor Cyclopropanes. Angew. Chem., Int. Ed. 2014, 53, 5504−5523. (c) Carson, C. A.; Kerr,

M. A. Heterocycles from cyclopropanes: applications in natural product synthesis. Chem. Soc. Rev. 2009, 38, 3051−3060. (d) De Simone, F.; Waser, J. Cyclization and Cycloaddition Reactions of Cyclopropyl Carbonyls and Imines. Synthesis 2009, 2009, 3353−3374. (e) Reissig, H.- U.; Zimmer, R. Donor-Acceptor-Substituted Cyclopropane Derivatives and their Application in Organic Synthesis. Chem. Rev. 2003, 103, 1151−1196. (f) Fumagalli, G.; Stanton, S.; Bower, J. F. Recent Methodologies That Exploit C−C Single-Bond Cleavage of Strained Ring Systems by Transition Metal Complexes. Chem. Rev. 2017, 117, 9404−9432. (g) Mack, D. J.; Njardarson, J. T. Recent Advances in the Metal-Catalyzed Ring Expansions of Threeand Four- Membered Rings. ACS Catal. 2013, 3, 272−286. (13) (a) Geyer, C.; Dinjus, E.; Schindler, S. Reactions of Aldehydes with Carbon Dioxide at Nickel(0) Centers. A Detailed Kinetic Analysis. Organometallics 1998, 17, 98−103. (b) Ogoshi, S.; Ueta, M.; Arai, T.; Kurosawa, H. AlMe3-Promoted Oxidative Cyclization of η2Alkene and η2-Ketone on Nickel(0). Observation of Intermediate in Methyl Transfer Process. J. Am. Chem. Soc. 2005, 127, 12810−12811. (14) (a) Yadav, V. K.; Balamurugan, R. Silicon-Assisted Ring Opening of Donor−Acceptor Substituted Cyclopropanes. An Expedient Entry to Substituted Dihydrofurans. Org. Lett. 2001, 3, 2717−2719. (b) Ma, S.; Lu, L.; Zhang, J. Catalytic Regioselectivity Control in Ring-Opening Cycloisomerization of Methylene- or Alkylidenecyclopropyl Ketones. J. Am. Chem. Soc. 2004, 126, 9645− 9660. (15) Young, I. S.; Kerr, M. A. A Homo [3 + 2] Dipolar Cycloaddition: The Reaction of Nitrones with Cyclopropanes. Angew. Chem., Int. Ed. 2003, 42, 3023−3026. (16) Malmgren, J.; Santoro, S.; Jalalian, N.; Himo, F.; Olofsson, B. Arylation with Unsymmetrical Diaryliodonium Salts: A Chemoselectivity Study. Chem. - Eur. J. 2013, 19, 10334−10342. (17) Clive, D. L. J.; Liu, D. Z. Synthesis of the otteliones A and B: Use of a cyclopropyl group as both a steric shield and a vinyl equivalent. Angew. Chem., Int. Ed. 2007, 46, 3738−3740. (18) (a) Dutta, M.; Mandal, S. M.; Pegu, R.; Pratihar, S. β-Arylation of oxime ethers using diaryliodonium salts through activation of inert C(sp)−H bonds using a palladium catalyst. J. Org. Chem. 2017, 82, 2193−2198. (b) Takebayashi, S.; John, J. M.; Bergens, S. H. Desymmetrization of meso-Cyclic Imides via Enantioselective Monohydrogenation. J. Am. Chem. Soc. 2010, 132, 12832−12834. (19) (a) Wang, Y.; Chen, C.; Peng, J.; Li, M. Copper(II)-Catalyzed Three-Component Cascade Annulation of Diaryliodoniums, Nitriles, and Alkynes: A Regioselective Synthesis of Multiply Substituted Quinolines. Angew. Chem., Int. Ed. 2013, 52, 5323−5327. (b) Peng, J.; Chen, C.; Wang, Y.; Lou, Z.-B.; Li, M.; Xi, C.; Chen, H. Direct Vicinal Disubstitution of Diaryliodonium Salts by Pyridine N - oxides and N amidates by a 1,3 - Radical Rearrangement. Angew. Chem., Int. Ed. 2013, 52, 7574−7578. (c) Wang, Y.; Chen, C.; Zhang, S.; Lou, Z.; Su, X.; Wen, L.; Li, M. A Concise Construction of Polycyclic Quinolines via Annulation of ω-Cyano-1-alkynes with Diaryliodonium Salts. Org. Lett. 2013, 15, 4794−4797. (d) Pang, X.; Chen, C.; Su, X.; Li, M.; Wen, L. Diverse Tandem Cyclization Reactions of o-Cyanoanilines and Diaryliodonium Salts with Copper Catalyst for the Construction of Quinazolinimine and Acridine Scaffolds. Org. Lett. 2014, 16, 6228− 6231. (e) Guo, W.; Li, S.; Tang, L.; Li, M.; Wen, L.; Chen, C. Synthesis of 6-(Arylthio)phenanthridines by Copper-Catalyzed Tandem Reactions of 2-Biaryl Isothiocyanates with Diaryliodonium Salts. Org. Lett. 2015, 17, 1232−1235. (f) Peng, J.; Chen, C.; Xi, C. βArylation of oxime ethers using diaryliodonium salts through activation of inert C(sp)−H bonds using a palladium catalyst. Chem. Sci. 2016, 7, 1383−1387. (g) Sheng, J.; Su, X.; Cao, C. Y.; Chen, C. Synthesis of benzo[1,3]oxazines via copper(I)-catalyzed cascade annulation of nitriles, aldehydes and diaryliodonium salts. Org. Chem. Front. 2016, 3, 501−504. (20) Bowman, R. K.; Johnson, J. S. Nickel-Catalyzed Rearrangement of 1-Acyl-2-vinylcyclopropanes. A Mild Synthesis of Substituted Dihydrofurans. Org. Lett. 2006, 8, 573−576.

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