A study of the selectivity and stereospecificity of the hydrogenation of n-pentynes on a skeletal nickel catalyst

Abstract

THERE are no data in the literature on the catalytic hydrogenation ofpent1-yne. In papers [1-3] it is shown that the hydrogenation of pent-2-yne on a Pd catalyst gives cis-pent-2-ene. In a preceding investigation [4] we established that hex-l-yne hydrogenates on a skeletal nickel catalyst non-selectively. On the other hand, hex-2-yne and hex-3-yne, under analogous conditions, hydrogenate with a high degree of selectivity and stercospecificity. Similar results were obtained in the hydrogenation of a triple bond on Pd catalysts [5-7]. In the present work, the influence of the nature of the solvent, the concentration of the acetylenic hydrocarbon, and the amount of catalyst on the rate of selectivity, and stereospecificity of the hydrogenation of pent1-yne and pent-2-yne has been studied.