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Dimethyl carbonate (DMC) is an environmental benign chemical compound and unique intermediate with versatile chemical reactivity which has attracted increasing interest from both practical and fundamental point of view in recent years [1,2].With increasing demands for a safer and environmentally favorable process for DMC synthesis, it has been of great interest to develop non-phosgene to prepare DMC.[3,4] Several phpsgene-free approaches have been known for DMC production so far.Among them, the direct oxidative carbonylation of methanol has shown to be the most promising processes for the production of DMC.The copper-organic coordination compounds, including Cu(phen)Cl2, Cu(phen)2Cl2 and Cu(phen)3Cl2, were prepared by the reaction of 1,10-Phenanthroline with copper chloride in methanol solution.The copper(Ⅱ[) complexes were characterized by infrared spectroscopy, elemental analyses, X-ray powder diffraction and thermogravimetric analysis, and its catalytic performances in the oxidative carbonylation of methanol were investigated.The results showed that Cu(phen)Cl2 exhibited the more activity and selectivity than the mixture of copper chloride and 1,10-Phenanthroline.Among copper complexes, Cu(phen)Cl2 had the best activity and selectivity because the introduction of ligand changed the density of copper electron cloud, and improved the redox property of the copper(Ⅱ) complex in the oxidative carbonylation of methanol to DMC.The TON could reach 39.0 mol DMC·molcu-1 with the selectivity of 93.3% under the reaction conditions of temperature 393 K, pressure 4.0 MPa, ratio of partial pressure of O2 to CO 19 ∶ 1 (below the explosion limit of CO) and the mass concentration of catalyst in methanol 0.004 g · ml-1.