CO 2 -Promoted and Copper-Catalyzed Dehydroxylative Coupling of Benzylic Alcohols by the NaBH 4 /I 2 System.

An efficient and CO 2 -promoted dehydroxylative coupling of benzylic alcohols catalyzed by ligand-free cuprous chloride has been achieved. The discovered catalytic reductive coupling reaction is a newly C-C bond-forming transformation of alcohols. Mechanistic insight is gained through control reactions.