(n+3)-Cyclization for the Formation of Benzo[7]annulene Derivatives via a [1,4]-Hydride Shift: A Novel Cyclization Mode Involving an Internal Redox Reaction

Abstract

We report a unique synthetic route to benzo[7]annulene derivatives. When benzylidene malonates having a 1-(N,N-dialkylamino)alkyl group at the ortho-position are treated with a stoichiometric amount of M(OTf)₃ (M = Sc, Yb, Gd), three transformations ([1,4]-hydride shift/isomerization into an enamine/intramolecular Stork enamine acylation) proceed sequentially to afford various benzo[7]annulene derivatives in moderate chemical yields. To our knowledge, the present reaction is the first example of an internal redox reaction involving a [1,n]-hydride shift/(n+3)-cyclization process.

Key words

C–H bond functionalization - redox process - carbocycles - hydride shift - (n+3)-cyclization - benzo[7]annulene

Publication History

Received: 15 February 2024

Accepted after revision: 14 March 2024

Accepted Manuscript online:
14 March 2024

Article published online:
04 April 2024

• References and Notes


For recent reviews on C–H activation, see:
• 1a Godula K, Sames D. Science 2006; 312: 67
• 1b Bergman RG. Nature 2007; 446: 391
• 1c Alberico D, Scott ME, Lautens M. Chem. Rev. 2007; 107: 174
• 1d Davies HM. L, Manning JR. Nature 2008; 451: 417
• 1e Chen X, Engle KM, Wang D.-H, Yu J.-Q. Angew. Chem. Int. Ed. 2009; 48: 5094
• 1f Jazzar R, Hitce J, Renaudat A, Sofack-Kreutzer J, Baudoin O. Chem. Eur. J. 2010; 16: 2654
• 1g Lyons TW, Sanford MS. Chem. Rev. 2010; 110: 1147
• 1h Davies HM. L, Du Bois J, Yu J.-Q. Chem. Soc. Rev. 2011; 40: 1855
• 1i Brückl T, Baxter RD, Ishihara Y, Baran PS. Acc. Chem. Res. 2012; 45: 826
• 1j Qin Y, Lv J, Luo S. Tetrahedron Lett. 2014; 55: 551
• 1k Davies HM. L, Morton D. J. Org. Chem. 2016; 81: 343
• 1l See also a highlight on visible-light photocatalysis: Hu X.-Q, Chen J.-R, Xiao W.-J. Angew. Chem. Int. Ed. 2017; 56: 1960

For recent reviews on internal redox processes, see:
• 2a Tobisu M, Chatani N. Angew. Chem. Int. Ed. 2006; 45: 1683
• 2b Peng B, Maulide N. Chem. Eur. J. 2013; 19: 13274
• 2c Wang L, Xiao J. Adv. Synth. Catal. 2014; 356: 1137
• 2d Haibach MC, Seidel D. Angew. Chem. Int. Ed. 2014; 53: 5010
• 2e Kwon SJ, Kim DY. Chem. Rec. 2016; 16: 1191
• 2f An X.-D, Xiao J. Org. Chem. Front. 2021; 8: 1364
• 2g Mori K. Bull. Chem. Soc. Jpn. 2022; 95: 296
• 2h Wang L, Xiao J. Org. Chem. Front. 2022; 9: 5041
• 2i Mori K, Okawa H. Tetrahedron Lett. 2022; 110: 154178
• 2j Shen Y.-B, Hu F, Li S.-S. Tetrahedron 2022; 127: 133089

For selected examples of internal redox reactions developed by our group, see:
• 3a Mori K, Sueoka S, Akiyama T. Chem. Lett. 2011; 40: 1386
• 3b Mori K, Sueoka S, Akiyama T. J. Am. Chem. Soc. 2011; 133: 2424
• 3c Mori K, Ehara K, Kurihara K, Akiyama T. J. Am. Chem. Soc. 2011; 133: 6166
• 3d Yoshida T, Mori K. Chem. Commun. 2017; 53: 4319
• 3e Yokoo K, Mori K. Chem. Commun. 2017; 53: 4319
• 3f Yoshida T, Mori K. Chem. Commun. 2018; 54: 12686
• 3g Tamura R, Kitamura E, Tustsumi R, Yamanaka M, Akiyama T, Mori K. Org. Lett. 2019; 21: 2383
• 3h Otawa Y, Mori K. Chem. Commun. 2019; 55: 13856
• 3i Yokoo K, Mori K. Org. Lett. 2020; 22: 244
• 3j Sakai D, Machida M, Mori K. Tetrahedron Lett. 2021; 83: 153408
• 3k Hoshino D, Mori K. Org. Lett. 2021; 23: 9403

For double C(sp³)–H bond functionalization by sequential utilization of the internal redox reaction, see:
• 4a Mori K, Kurihara K, Yabe S, Yamanaka M, Akiyama T. J. Am. Chem. Soc. 2014; 136: 3744
• 4b Mori K, Isogai R, Kamei Y, Yamanaka M, Akiyama T. J. Am. Chem. Soc. 2018; 140: 6203
• 4c Mori K, Umehara N, Akiyama T. Chem. Sci. 2018; 9: 7327
• 4d Kataoka M, Otawa Y, Ido N, Mori K. Org. Lett. 2019; 21: 9334
• 4e Yokoo K, Sakai D, Mori K. Org. Lett. 2020; 22: 5801

For selected examples of internal redox reactions, see:
• 5a Pastine SJ, McQuaid KM, Sames D. J. Am. Chem. Soc. 2005; 127: 12180
• 5b Polonka-Bálint A, Saraceno C, Ludányi K, Bényei A, Mátyus P. Synlett 2008; 2846
• 5c Zhang C, Kanta De C, Mal R, Seidel D. J. Am. Chem. Soc. 2008; 130: 416
• 5d McQuaid KM, Sames D. J. Am. Chem. Soc. 2009; 131: 402
• 5e Shinkai D, Murase H, Hata T, Urabe H. J. Am. Chem. Soc. 2009; 131: 3166
• 5f Ruble JC, Hurd AR, Johnson TA, Sherry DA, Barbachyn M, Toogood RP. L, Bundy GL, Graber DR, Kamilar GM. J. Am. Chem. Soc. 2009; 131: 3991
• 5g Vadola PA, Sames D. J. Am. Chem. Soc. 2009; 131: 16525
• 5h Zhou G, Zhang J. Chem. Commun. 2010; 46: 6593
• 5i Jurberg ID, Peng B, Wöstefeld E, Wasserloos M, Maulide N. Angew. Chem. Int. Ed. 2012; 51: 1950
• 5j Sugiishi T, Nakamura H. J. Am. Chem. Soc. 2012; 134: 2504
• 5k Gao X, Gaddam V, Altenhofer E, Tata RR, Cai Z, Yongpruksa NA, Garimallaprabhakaran K, Harmata M. Angew. Chem. Int. Ed. 2012; 51: 7016
• 5l Chen D.-F, Han Z.-Y, He Y.-P, Yu J, Gong L.-Z. Angew. Chem. Int. Ed. 2012; 51: 12307
• 5m Cera G, Chiarucci M, Dosi F, Bandini M. Adv. Synth. Catal. 2013; 335: 2227
• 5n Alajarin M, Bonillo B, Marin-Luna M, Sanchez-Andrada P, Vidal A. Chem. Eur. J. 2013; 19: 16093
• 5o Vidal A, Martin-Luna M, Alajarin M. Eur. J. Org. Chem. 2014; 878
• 5p Richer MT, Breugst M, Platonova AYu, Ullrich A, Dieckmann A, Houk KN, Seidel D. J. Am. Chem. Soc. 2014; 136: 6123
• 5q Chang Y.-Z, Li M.-L, Zhao W.-F, Wen X, Sun H, Xu Q.-L. J. Org. Chem. 2015; 80: 9620
• 5r Shen Y.-B, Li L.-F, Xiao M.-Y, Yang J.-M, Liu Q, Xiao J. J. Org. Chem. 2019; 84: 13935
• 5s Shen Y.-B, Wang L.-X, Sun Y.-M, Dong F.-Y, Yu L, Liu Q, Xiao J. J. Org. Chem. 2020; 85: 1915
• 5t Hu F, Li X, Ding Z, Wang L, Ge C, Xu L, Li S.-S. ACS Catal. 2022; 12: 943
• 5u An X.-D, Shao D.-Y, Qiu B, Xiao J. Org. Lett. 2023; 25: 2432
• 5v Hu F, Sun Z, Pan M, Wang L, Xu L, Liu X.-L, Li S.-S. Green Chem. 2023; 25: 5134

For examples of enantioselective internal redox reactions, see:
• 6a Murarka S, Deb I, Zhang C, Seidel D. J. Am. Chem. Soc. 2009; 131: 13226
• 6b Kang YK, Kim SM, Kim DY. J. Am. Chem. Soc. 2010; 132: 11847
• 6c Cao W, Liu X, Wang W, Lin L, Feng X. Org. Lett. 2011; 13: 600
• 6d Zhou G, Liu F, Zhang J. Chem. Eur. J. 2011; 17: 3101
• 6e He Y.-P, Du Y.-L, Luo S.-W, Gong LZ. Tetrahedron Lett. 2011; 52: 7064
• 6f Chen L, Zhang L, Lv Z, Cheng J.-P, Luo S. Chem. Eur. J. 2012; 18: 8891
• 6g Zhang L, Chen L, Lv Z, Cheng J.-P, Luo S. Chem. Asian J. 2012; 7: 2569
• 6h Jiao Z.-W, Zhang S.-Y, He C, Tu Y.-Q, Wang S.-H, Zhang F.-M, Zhang Y.-Q, Li H. Angew. Chem. Int. Ed. 2012; 51: 8811
• 6i Kang YK, Kim DY. Adv. Synth. Catal. 2013; 355: 3131
• 6j Suh CW, Woo SB, Kim DY. Asian J. Org. Chem. 2014; 3: 399
• 6k Kang YK, Kim DY. Chem. Commun. 2014; 50: 222
• 6l Suh CW, Kim DY. Org. Lett. 2014; 16: 5374
• 6m Yu J, Li N, Chen D.-F, Luo S.-W. Tetrahedron Lett. 2014; 55: 2859
• 6n Cao W, Liu X, Guo J, Lin L, Feng X. Chem. Eur. J. 2015; 21: 1632
• 6o Li J, Preinfalk A, Malide N. J. Am. Chem. Soc. 2019; 141: 143
• 6p See also refs 3c and 4b.
• 7 Haibach MC, Deb I, Kanta De C, Seidel D. J. Am. Chem. Soc. 2011; 133: 2100
• 8a Li S.-S, Zhou L, Wang L, Zhao H, Yu L, Xiao J. Org. Lett. 2018; 20: 138
• 8b See also: Wang L.-X, Qiu B, An X.-D, Dong P.-Z, Liu R.-B, Xiao J. Green. Chem. 2021; 23: 8181
• 9 Suh CW, Kwon SJ, Kim DY. Org. Lett. 2017; 19: 1334
• 10a Sun Z, Hou R, Li S.-S, Wang X, Wang L, Hu F, Guo F.-W. Org. Lett. 2024; 26: 6
• 10b Dong Y, Hu F, Wu H, Guo F.-W, Wang L, Du F.-Y, Li S.-S. Org. Lett. 2024; 26: 332
• 11 Che X, Zheng L, Dang Q, Bai X. Synlett 2008; 2373
• 12 Wicker G, Schoch R, Paradies J. Org. Lett. 2021; 23: 3626

For selected reviews on the synthesis of medium-sized rings, see:
• 13a Molander GA. Acc. Chem. Res. 1998; 31: 603
• 13b Deiters A, Martin R. Chem. Rev. 2004; 104: 2199
• 13c Shiina I. Chem. Rev. 2007; 107: 239
• 13d Nguyen TV, Hartmann JM, Enders D. Synthesis 2013; 45: 845
• 13e Wang Y, Yu Z.-W. Acc. Chem. Res. 2015; 48: 2288
• 13f Mortensen KT, Osberger TJ, King TA, Sore HF, Spring DR. Chem. Rev. 2019; 119: 10288

For examples of [1,4]-hydride-shift-mediated C–H bond functionalization reactions, see:
• 14a Yang S, Li Z, Jian X, He C. Angew. Chem. Int. Ed. 2009; 48: 3999
• 14b Alajarin M, Martin-Luna M, Vidal A. Adv. Synth. Catal. 2011; 353: 557
• 14c Mori K, Kurihara K, Akiyama T. Chem. Commun. 2014; 50: 3729
• 14d Hoshino D, Mori K. Org. Biomol. Chem. 2020; 18: 6602
• 14e See also ref 4a.
• 15 Ramachary DB, Mondal R, Venkaiah C. Eur. J. Org. Chem. 2010; 3205
• 16 The best chemical yields are reported after conducting the catalyst screening (Sc(OTf)₃, Yb(OTf)₃, and Gd(OTf)₃) on each substrate.
• 17 The production of N,N-diethyl derivative 4f also suggested the low possibility of the [1,6]-hydride shift process.