Synthesis of 2-Hydroxymethyl Ketones by Ruthenium Hydride-Catalyzed Cross-Coupling Reaction of α,β-Unsaturated Aldehydes with Primary Alcohols

The cross-coupling reaction of alpha,beta-unsaturated aldehydes with primary alcohols to give 2-hydroxymethyl ketones was achieved using RuHCl(CO)(PPh(3))(3) as a catalyst. This atom-economical reaction is likely to proceed via the hydroruthenation of alpha,beta-unsaturated aldehydes followed by an aldol reaction of the resultant enolates with aldehydes to give alpha-formylated ketones, which undergo transfer hydrogenation with primary alcohols leading to alpha-hydroxymethyl ketones. The reduction step can generate aldehydes, participating in the next catalytic cycle.