Homogeneous Catalysis (￥3). Hydrogenation of Acrylonitrile with trans-Chlorocarbonylbis(triphenylphosphine)rhodium(￥°)

摘要

It has been found that the acrylonitrile solution of trans-RhCl(CO)(Ph3P)2 produces propionitrile catalytically at 90∩ under PH2 = 3 atm. This catalytic hydrogenation proceeds only for a certain period of time producing ca. 50 moles of propionitrile per mole of the rhodium complex. The hydrogenation with trans-RhCl(CO)(Ph3P)2 in the presence of formaldehyde is much faster than in the absence of formaldehyde, and continues without a decrease in the rate for a prolonged period of time. It is suggested that the hydrogenation with trans-RhCl(CO)(Ph3P)2 proceeds through the unsaturated route initiated by the dissociation of CO from trans-RhCl(CO)(Ph3P)2 to give coordinatively unsaturated RhCl(Ph3P)2.