A Cascade of Acid-Promoted C–O Bond Cleavage and Redox Reactions: From Oxa-Bridged Benzazepines to Benzazepinones

Abstract

A sequence of C-O bond cleavage and redox reactions in oxa-bridged azepines was realized under acid promoted conditions. This protocol provides an atom-economical and straightforward approach to access benzo[b]azepin-5(2H)-ones in high yields. The formal synthesis of tolvaptan was achieved by exploiting this new transformation.