Facile construction of hydrogenated azepino[3,2,1-hi]indoles by Rh(iii)-catalyzed C-H activation/[5+2] annulation of N-cyanoacetylindolines with sulfoxonium ylides

Rhodium(iii)-catalyzed regio- and chemoselective [5 + 2] annulation between N-(cyanoacetyl)indolines and sulfoxonium ylides has been realized, leading to efficient construction of seven-membered rings under mild conditions. This reaction proceeded via C-H activation with sulfoxonium ylides as carbene synthons.