Stoichiometric hydrogenation of α,β-unsaturated ketones by HCo(CO)4

Article abstract of DOI:10.1016/0022-328X(88)80049-4

A study of the kinetics of the stoichiometric hydrogenation of α,β-unsaturated ketones by HCo(CO)4 led to the rate expression rate = k_obs^2-1.The reaction is catalyzed by Co2(CO)8 and shows a small inverse isotope effect with DCo(CO)4.Although the analogous reaction with the α,β-unsatureted ester dimethyl α-methylidenesuccinate (dimethyl itaconate, DMI) is also catalyzed by Co2(CO)8 and also shows an inverse isotope effect, the rate expression involves a first order dependence on HCo(CO)4.Furthermore, contrary to the behavior of simple acrylates, which have been shown elsewhere to conform to the same kinetic expression, no aldehydic product is produced.A mechanism consistent with the results is proposed.