Mesoporous organic Pd-containing catalysts for the selective hydrogenation of conjugated hydrocarbons

Palladium catalysts supported on ordered organic mesoporous polymers were synthesized. The catalysts are characterized by the narrow size distribution of palladium nanoparticles with an average particle size of 2.2-5.2 nm. They demonstrate high catalytic activity and selectivity in phenylacetylene hydrogenation (896-2590 min(-1), selectivity 89-98%). High activity and selectivity for alkenes are observed in the hydrogenation of conjugated dienes (for isoprene, TOF = 1850-5000 min(-1), selectivity 99%; for 2,5-dimethyl-2,4-hexadiene, TOF = = 1294-2400 min(-1), selectivity 100%; for 1,4-diphenyl-1,3-butadiene, TOF = 14-22 min(-1), selectivity 7-16%). A dependence of the selectivity on the nature of the support and substrate was found for the hydrogenation of 1,4-diphenyl-1,3-butadiene.