CATALYTIC REACTION .1. CATALYTIC 1,4-HYDROGENATION OF ALPHA,BETA-UNSATURATED ALDEHYDES AND KETONES USING SC-1 NICKEL BORIDE

Ex-situ generated SC-1 nickel boride (SC-1 Ni2B), prepared by refluxing nickel chloride and sodium borohydride in methanol, is used in the selective 1,4-hydrogenation of alpha, beta-unsaturated ketones and aldehydes or one atmospheric pressure. Previous studies of in-situ generated Ni2B have had the disadvantage of the undesirable side reaction of sodium borohydride with the various functional groups. In contrast, our catalyst cleanly gives the corresponding saturated aldehyde or ketone with no detectable amounts of saturated alcohol. Furthermore, the degree of substitution of the double bond plays a significant role in the race of hydrogenation. While unsaturated carbonyl compounds containing di- and tri- substituted double bonds are readily hydrogenated tetra-substituted double bond containing carbonyl compounds are highly unreactive.