Hydrogenation of phenylacetylene and 3-phenylpropyne using Rh(diene) complexes under homogeneous and heterogeneous conditions
2010
Abstract
Hydrogenation of phenylacetylene (PA) and 3-phenylpropyne (PP) was carried out using [Rh(diene)Cl](2) complexes (diene is hexadiene (HD), cycloocta-1,5-diene (COD), norborna-2,5-diene (NBD)) in their immobilized forms and compared with hydrogenation in homogeneous arrangement. Immobilization brings significant increase of the catalytic activity and product selectivity in the step-wise hydrogenation to corresponding vinyl-resp. allyl-benzenes.
Diene-ligand effect was apparent in PA hydrogenation: the product selectivity decreased in order Rh(HD) > Rh(NBD) > Rh(COD) and catalytic activity decreased in order Rh(HD) > Rh(COD) > Rh(NBD).