Stereoselective hydrogenation of phenyl alkyl acetylenes on pillared clays supported palladium catalysts

The stereoselective hydrogenation of phenyl alkyl acetylenes at 298 K and atmospheric pressure of hydrogen over Pd-supported catalysts has been studied. The catalysts were prepared by impregnation of Al-PILC and Ca-Mont with Pd(acac)2 precursor, with a metal content close to 1 wt %. All the solids were characterised by nitrogen adsorption-desorption isotherms at 77 K, TPR, H2 and CO chemisorption, XRD and TEM measurements. The reactions were found to be zero order concerning the alkyne concentration. All catalysts displayed high selectivity to cis-alkene isomer being the 1%Pd/Al-PILC the most active catalyst.