A new cycloaddition profile for ortho-quinone methides: photoredox-catalyzed [6+4] cycloadditions for synthesis of benzo[b]cyclopenta[e]oxepines

Abstract

Visible-light-induced [6+4] cycloaddition reactions of ortho-quinone methides have been developed. The reaction of ortho-quinone methides with pentafulvenes in the presence of a thioxanthylium photoredox catalyst afforded benzo[b]cyclopenta[e]oxepines. The present reaction represents a promising tool for the synthesis of natural products and bioactive compounds that contain a benzoxepine structure.