Catalytic Hydrogenation of Unsaturated Esters with Metallic Nickel/Zinc/H₂O/Ethanol Catalyst System

Abstract

Under nitrogen atmosphere diethyl maleate was hydrogenated to give diethyl succinate in a high yield with metallic nickel/Zn/H₂O/EtOH catalyst system in the presence of a large amount of zinc powder and water. Metallic nickel was an active species for the hydrogenation and zinc powder and water were reagents to produce hydrogen. Benzylideneaniline was hydrogenated to give N-phenylbenzylamine in a moderate yield under the reaction conditions and it was appreciably hydrolyzed to afford aniline and benzaldehyde at the same time.