Pd‐Catalyzed Umpolung of η³‐Benzylpalladium Enabled the Construction of All‐Carbon α‐Vinyl Quaternary Aldehydes

Abstract

A Pd-catalyzed decarboxylative approach for the construction of 2-allyl-2,2-diarylacetaldehydes via dearomative umpolung strategy is reported. The reaction is applicable to a number of cyclic carbonates or allylic acetates featuring with different functional groups. These reactions could be performed in a gram-scale but without loss of the reaction efficiency. The control experiments suggest that the reaction proceeds though a palladium catalyzed dearomative decarboxylation step followed by an umpolung nucleophilic attack.