Potassium Persulfate/Tributylamine-Mediated Alkylation/Annulation of N-Arylacrylamides with Alkyl Iodides

Abstract

We report a catalyst-free method for the alkylation/annulation of N-arylacrylamides to give the corresponding 3-alkyl-2-oxo-2,3-dihydro-1H-indoles by using alkyl iodides as precursors of alkyl radicals. These reactions occur at moderate temperatures and are mediated by easily accessible K₂S₂O₈ and Bu₃N.

Key words

arylacrylamides - cyclization - oxindoles - halogen-atom transfer - alkylation

• References and Notes

• 1a Kiefer S, Mertz AC, Koryakina A, Hamburger M, Küenzi P. Eur. J. Pharm. Sci. 2010; 40: 143
• 1b Christodoulou MS, Nicoletti F, Mangano K, Chiacchio MA, Facchetti G, Rimoldi I, Beccalli EM, Giofrè S. Bioorg. Med. Chem. Lett. 2020; 30: 126845
• 1c Kaur M, Singh M, Chadha N, Silakari O. Eur. J. Med. Chem. 2016; 123: 858
• 1d Lai Y, Ma L, Huang W, Yu X, Zhang Y, Ji H, Tian J. Bioorg. Med. Chem. Lett. 2010; 20: 7349
• 1e Chen G, Jiang L, Dong L, Wang Z, Xu F, Ding T, Fu L, Fang Q, Liu Z, Shan X, Liang G. Drug Des., Dev. Ther. 2014; 8: 1869
• 2a Liu T, Zheng D, Wu J. Org. Chem. Front. 2017; 4: 1079
• 2b Xu S.-M, Chen J.-Q, Liu D, Bao Y, Liang Y.-M, Xu P.-F. Org. Chem. Front. 2017; 4: 1331
• 2c Wan W, Li J, Ma G, Chen Y, Jiang H, Deng H, Hao J. Org. Biomol. Chem. 2017; 15: 5308
• 2d Bagal DB, Park S.-W, Song H.-J, Chang S. Chem. Commun. 2017; 53: 8798
• 2e Karmaker P, Qiu J, Wu D, Yin H, Chen F.-X. Synlett 2018; 29: 954
• 2f Lu M, Liu Z, Zhang J, Tian Y, Qin H, Huang M, Hu S, Cai S. Org. Biomol. Chem. 2018; 16: 6564
• 2g Kanyiva KS, Makino S, Shibata T. Chem. Asian J. 2018; 13: 496
• 2h Yang Z, Tang A. Synlett 2019; 30: 1061
• 2i Zhang T, Chen B, Wang W, Zhang Q, Wang P, Wan W, Deng H, Hao J, Jiang H. Asian J. Org. Chem. 2019; 8: 671
• 2j Manoharan R, Logeswaran R, Jeganmohan M. J. Org. Chem. 2019; 84: 14830
• 2k Yang Z, Cheng Y, Long J, Feng X, Tang R, Wei J. New J. Chem. 2019; 43: 18760
• 2l Lu M, Zhang T, Tan D, Chen C, Zhang Y, Huang M, Cai S. Adv. Synth. Catal. 2019; 361: 4237
• 2m Wang YZ, Lin WJ, Zou JY, Yu W, Liu XY. Adv. Synth. Catal. 2020; 362: 3116
• 2n Chen L, Ma P, Yang B, Zhao X, Huang X, Zhang J. Chem. Commun. 2021; 57: 1030
• 2o Lu K, Lei L, Wei Q, Zhou T, Jia X, Li Q, Zhao X. Tetrahedron Lett. 2021; 67: 152864
• 2p Kotipalli R, Nagireddy A, Reddy MS. Org. Biomol. Chem. 2022; 20: 2609
• 2q Mao L.-L, Zhou A.-X, Zhu X.-H, Quan L.-X, Chen F, Wan J.-P, Lai Y.-L. Org. Biomol. Chem. 2022; 20: 1196
• 3a Xu Z, Jia R, Ma Z, Cao S, Shen L, Ji H. Synlett 2019; 30: 1909
• 3b Liu D, Zhuang S, Chen X, Yu L, Yu Y, Hu L, Tan Z. Tetrahedron Lett. 2018; 59: 612
• 3c Li Z, Zhang Y, Zhang L, Liu Z.-Q. Org. Lett. 2014; 16: 382
• 3d Dai Q, Yu J, Jiang Y, Guo S, Yang H, Cheng J. Chem. Commun. 2014; 50: 3865
• 3e Li Z, Cui X, Niu L, Ren Y, Bian M, Yang X, Yang B, Yan Q, Zhao J. Adv. Synth. Catal. 2017; 359: 246
• 3f Xie Z, Li P, Hu Y, Xu N, Wang L. Org. Biomol. Chem. 2017; 15: 4205
• 4a Zhao Y, Li Z, Sharma UK, Sharma N, Song G, Van der Eycken EV. Chem. Commun. 2016; 52: 6395
• 4b Pan C, Zhang H, Zhu C. Org. Biomol. Chem. 2015; 13: 361
• 5a Jia F, Liu K, Xi H, Lu S, Li Z. Tetrahedron Lett. 2013; 54: 6337
• 5b Gao R.-X, Luan X.-Q, Xie Z.-Y, Yang L, Pei Y. Org. Biomol. Chem. 2019; 17: 5262
• 5c Biswas P, Paul S, Guin J. Angew. Chem. Int. Ed. 2016; 55: 7756
• 6 Pan C, Fu Y, Ni Q, Yu J.-T. J. Org. Chem. 2017; 82: 5005
• 7 Ling A, Zhang L, Tan RX, Liu Z.-Q. J. Org. Chem. 2018; 83: 14489
• 8 Wu T, Zhang H, Liu G. Tetrahedron 2012; 68: 5229
• 9 Tang Q, Liu X, Liu S, Xie H, Liu W, Zeng J, Cheng P. RSC Adv. 2015; 5: 89009
• 10 Lu Y, Fang C.-Z, Liu Q, Li B.-L, Wang Z.-X, Chen X.-Y. Org. Lett. 2021; 23: 5425
• 11a Xie J, Xu P, Li H, Xue Q, Jin H, Cheng Y, Zhu C. Chem. Commun. 2013; 49: 5672
• 11b Sun Z, Huang H, Wang Q, Huang C, Mao G, Deng G.-J. Org. Chem. Front. 2022; 9: 3506
• 11c Gao X, Dong W, Hu B, Gao H, Yuan Y, Xie X, Zhang Z. RSC Adv. 2017; 7: 49299
• 11d Sakamoto R, Hirama N, Maruoka K. Org. Biomol. Chem. 2018; 16: 5412
• 12a Wang H, Guo L.-N, Duan X.-H. J. Org. Chem. 2016; 81: 860
• 12b Fan J.-H, Wei W.-T, Zhou M.-B, Song R.-J, Li J.-H. Angew. Chem. Int. Ed. 2014; 53: 6650
• 13a Muralirajan K, Kancherla R, Gimnkhan A, Rueping M. Org. Lett. 2021; 23: 6905
• 13b Du J, Wang X, Wang H, Wei J, Huang X, Song J, Zhang J. Org. Lett. 2021; 23: 5631
• 14a Constantin T, Juliá F, Sheikh NS, Leonori D. Chem. Sci. 2020; 11: 12822
• 14b Constantin T, Zanini M, Regni A, Sheikh SN, Juliá F, Leonori D. Science 2020; 367: 1021
• 15 tert-Butyl 4-[(1,3-Dimethyl-2-oxo-2,3-dihydro-1H-indol-3-yl)methyl]piperidine-1-carboxylate (3a); Typical Procedure A dried reaction tube charged with 1a (35 mg, 0.2 mmol), 2a (124.5 mg, 0.4mmol), and K₂S₂O₈ (0.6 mmol) was evacuated and backfilled with argon three times. MeCN (1.6 mL), H₂O (0.4 mL), and Bu₃N (1 mmol) were injected into the tube by syringe, and the mixture was heated at 70 ℃ for 12 h. The crude product was purified by column chromatography [silica gel, PE–EtOAc (4:1)] to give a brown oil; yield: 55.4 mg (80%); R_f = 0.3 (PE–EtOAc, 4:1). ¹H NMR (500 MHz, CDCl₃): δ = 7.28 (d, J = 7.7 Hz, 1 H), 7.16 (d, J = 7.4 Hz, 1 H), 7.07 (t, J = 7.5 Hz, 1 H), 6.85 (d, J = 7.8 Hz, 1 H), 3.84 (s, 2 H), 3.22 (s, 3 H), 2.51–2.32 (m, 2 H), 1.98 (dd, J = 14.1, 6.2 Hz, 1 H), 1.76 (dd, J = 14.1, 5.4 Hz, 1 H), 1.39 (s, 9 H), 1.32 (s, 3 H), 1.25 (s, 1 H), 1.15–1.00 (m, 3 H), 0.91–0.83 (m, 1 H).
• 16 Li X, Xu X, Hu P, Xiao X, Zhou C. J. Org. Chem. 2013; 78: 7343