Sulfonyl Radical-Induced\nRegioselective Cyclization\nof Enamide–Olefin To Form Sulfonylated 6–7-Membered\nCyclic Enamines

Remarkable\nprogress has been made in the radical cascade cyclization\nof heteroaryl- or aryl-tethered alkenes to construct benzene-fused\nframeworks via the cracking of aryl C–H bonds. In contrast,\nthe radical cascade cyclization of linear dienes through the cracking\nof vinyl C–H bonds to construct nonbenzene-fused ring frameworks\nwith endocyclic double bonds has significantly lagged behind, and\nmajor advances have largely been restricted to the generation of 5-membered\nheterocycles, such as pyrrolinones. Herein, we report the silver-mediated\nregioselective sulfonylation-cyclization of linear dienes with sodium\nsulfinates to form sulfonylated 6- and 7-membered cyclic enamines.