Oxidative carbonylation of methanol to dimethyl carbonate by chlorine-free homogeneous and immobilized 2,2'-bipyrimidine modified copper catalyst

A chlorine-free catalyst, prepared in situ from Cu( II) acetate and 2,2 '-bipyrimidine, can be used for the oxidative carbonylation of methanol to dimethyl carbonate. In situ high pressure IR and NMR spectroscopic studies suggest the formation of [ Cu( 2,2 '-bipyrimidine)( CO)-( OMe)] as one of the key intermediates. The catalytic performance of the 2,2 '-bipyrimidinemodified Cu-catalyst is similar to the CuCl-based system. The chlorine free catalyst can be immobilized by using the copolymer of 5-vinyl- 2,2 '-bipyrimidine and styrene.