Photoredox-catalyzed sequential Dowd–Beckwith ring expansion and C–H functionalization of THIQs

Abstract

An efficient tandem Dowd–Beckwith ring expansion/C–H functionalization of tetrahydroisoquinolines (THIQs) upon photocatalysis is disclosed, providing a unique idea to connect important medium-sized cycloalkanones with THIQ skeletons, along with the construction of an all-carbon quaternary carbon center. This protocol features step- and atom-economy, mild conditions and good functional group tolerance.