Transition metal free transfer hydrogenation of ketones promoted by 1,3-diarylimidazolium salts and KOH

An efficient transition metal free and greener catalytic system was developed for the selective transfer hydrogenation of saturated ketones to alcohols. This was achieved by the use of 1,3-diarylimidazolium salts in the presence of KOH as a promoter for the reaction. When the range of substrates was expanded to include unsaturated ketones, selective reduction of the double bond occurred. The catalyst efficiency was comparable to some established transition metal catalyzed systems. The current system utilizes mild aerobic reaction conditions compared to the inert atmosphere conditions required for the corresponding metal based systems.