Polymer-supported palladium-manganese bimetallic catalyst for the oxidative carbonylation of amines to carbamate esters

The polymer-supported bimetallic catalyst PVP-PdCl2-MnCl2 (PVP=poly(N-vinyl -2-pyrrolidone)) exhibits high activity and selectivity for the oxidative c arbonylation of amines with carbon monoxide and oxygen to carbamate esters under atmospheric pressure in the presence of a base (NaOAc). This catalyst is prepared by the addition of MnCl2 to the alcoholic solution of PVP-PdCl 2 in situ. A remarkable bimetallic synergic effect and the role of PVP in P VP-PdCl2-MXn (MXn=the second transition metal component such as NiCl2, CoCl 2, MnCl2 and FeCl3) gives rise to an obvious increase in the conversion and selectivity for the reaction. Among the second metal components tested, Mn -Pd exerts the strongest synergic effect. (C) 1999 Elsevier Science B.V. Al l rights reserved.