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′-bipyrimidine- modified 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. © 2007 Institute of Organic Chemistry and Biochemistry.