Iridium-catalyzed [3+2] cyclization of terminal alkynes with sulfoxonium ylides to construct 2,5-disubstituted furans

Abstract

A novel iridium-catalyzed [3+2] cyclization of sulfoxonium ylides with terminal alkynes for the synthesis of 2,5-disubstituted furans has been demonstrated. This protocol features a broad substrate scope, mild reaction conditions, and good to excellent yields. Mechanistic studies indicate that the reaction may involve the C(sp)–H bond insertion of sulfoxide ylides to generate allenones, followed by cyclization. In addition, late-stage functionalization of complex architectures shows the utility of this method.