A novel homogeneous catalyst made of poly(N-vinyl-2-pyrrolidone)-CuCl ₂ complex for the oxidative carbonylation of methanol to dimethyl carbonate

A new type of homogeneous catalyst for dimethyl carbonate (DMC) synthesis by oxidative carbonylation of methanol in the liquid-phase reaction was investigated. The polymer-bound monometallic PVP-CuCl ₂ catalyst (PVP, poly(N-vinyl-2-pyrrolidone)) prepared by the combination of an alcoholic solutions of PVP and CuCl ₂ exhibits excellent catalytic performance for the oxidative carbonylation of methanol with carbon monoxide and oxygen to DMC under 3.0MPa (P _{O 2} =0.24MPa and P _{C O} =2.76MPa) pressure at temperature around 140-160 ^o C. The catalyst exhibits much higher activity and selectivity than non-supported CuCl ₂ in the DMC synthesis reaction. The remarkable increase in the conversion and selectivity is attributed to the presence of a strong complexation effect between Cu(II) and the amide ligands in the polymer chains.