Cu-Catalyzed Reductive Coupling of Allylic and Carbonyl Electrophiles

We report herein Cu-catalyzed syntheses of secondary and tertiary homoallylic alcohols. Compared to conventional carbonyl addition with nucleophilic allylation reagents, this process utilizes a reductive coupling strategy in which electrophilic allylic esters couple with carbonyl compounds with B₂pin₂ as the reductant. Notably, the approach employs an earth-abundant metal catalyst without using cryogenic conditions.