Investigation of the selectivity and stereospecificity in the hydrogenation of butyne-2-diol-1,4 on skeletal palladium, nickel, and cobalt catalysts

Abstract

1. In the presence of Pd/C, Ni, and Co skeletal catalysts, the hydrogenation of butyne-2-diol-1,4 proceeds with a high degree of selectivity (94–96%) and stereospecificity (95–97%). The main reaction product is cis-butenediol. 2. The formation of small amounts of butanediol and trans-butenediol is due to the mechanism of addition of hydrogen to butynediol and not to conversion of the butenediol formed. 3. Factors reducing the activity of the catalyst: aging, use of water as a solvent, introduction of alkali, and poisoning of the catalyst with pyridine, had no effect upon the selectivity and stereospecificity of the hydrogenation of butynediol. 4. Hydrogenation of cis-butenediol is accompanied by its stereoisomeric transformation. Transbutenediol is not isomerized under these conditions.