Ni-mediated Liquid Phase Reduction of Carbonyl Compounds in the Presence of Atmospheric Hydrogen1

An efficient reduction system of benzaldehyde with hydrogen under ambient pressure was developed using facile NiO catalyst. The non-aromatic solvents such as cyclohexane, tetrahydrofuran (THF) and n-hexane, and the additive with strong basicity e.g. KOH, were necessary for smooth conversion of the substrate. That the catalyst can be recovered and reused for nine times without loss of catalytic activity indicates that this catalyst is a recyclable one for benzaldehyde reduction.