Photoredox-Driven Deoxygenative Cross-Coupling of Alcohols with Carbonyl Compounds

Alcohols and carbonyl compounds are fundamental and abundant feedstock chemicals, whose orthogonal reactivities, aside from classical textbook chemistry, have been unstoppably pursued to overcome the limit of their inherent electronic features. Here we report a mild, photoredox-driven deoxygenative cross-coupling between benzylic alcohols and carbonyl compounds (aromatic aldehydes, aromatic ketones, and ketone esters). This well-designed open-shell chemistry rationally takes advantage of the photocatalytic generation of alkyl and ketyl radicals in a single photocatalysis cycle and PRE-directed radical–radical cross-coupling to forge the C–C bond formation, thereby offering direct access to sterically congested secondary and tertiary alcohols. The developed protocol delivers a broad range of benzylic-substituted alcohols in moderate to good yields by using abundant starting materials with high chemoselectivity, functional group tolerance, and operational simplicity. Mechanistic investigations and DFT calculations comprehensively support the radical-coupling process involving the concurrent generation of ketyl and benzyl radicals within a single photoredox cycle and chemoselective C–C bond formation.