Cupric bromide-derived complex: An effective homogeneous catalyst for oxidative carbonylation of methanol to dimethyl carbonate

Aiming at developing a homogeneous catalyst with low corrosiveness, CuBr₂ was selected as active species for the oxidative carbonylation of methanol. A series of N-containing ligands were introduced to improve the catalytic performance of CuBr₂. The effects of reaction conditions including CO/O₂ molar ratio, catalyst concentration, temperature, pressure, and time were investigated. The results show that the introduction of ligand can improve the catalytic performance of CuBr₂ obviously. The catalyst (C₃H₇)₄NBr/CuBr₂ exhibits the best catalytic performance, and 58.1% of methanol can be converted with DMC selectivity of 93.5% under the optimal reaction conditions. The increase of catalytic performance of CuBr₂ can be ascribed to the increase of electron density around Cu after the formation of complex with ligand.