Rhenium-Catalyzed Acceptorless Dehydrogenative Coupling via Dual Activation of Alcohols and Carbonyl Compounds

The rhenium hetaphydride complex was found to be a versatile, homogeneous catalyst for dehydrogenative functionalization of alcohol. The dehydrogenative C-C coupling of alcohols and carbonyl compounds was carried out in the absence Of base and hydrogen acceptors to afford a series of alpha,beta-unsaturated carbonyl compounds. A possible dual activation pathway was proposed by mechanistic investigations.