Cu(phen)Cl2催化甲醇氧化羰基化合成碳酸二甲酯

Synthesis of Dimethyl Carbonate from Oxidative Carbonylation of Methanol Catalyzed by Cu(phen)Cl_2

以CuCl2和邻菲啰啉(phen)为原料,在甲醇和乙醇混合溶剂中制备了Cu(phen)Cl2,采用傅里叶红外光谱、热重分析和H2程序升温还原对其进行了表征,并研究了其在甲醇氧化羰基化合成碳酸二甲酯(DMC)反应中的催化性能.结果表明,Cu(phen)Cl2不仅具有较高的热稳定性,而且因phen与Cu(Ⅱ)间的σ-π配位作用而具有较高的催化活性.在催化剂浓度0.011mol/L,反应温度150℃,反应压力4.0MPa和p(CO)/p(O2)=19的条件下,生成DMC的转化数(TON)可达51.5.研究还发现,反应存在诱导期,且TON随温度呈"M"形变化,据此提出了新的羰氧化反应机理.

The copper coordination compound Cu（phen）Cl2 was prepared by the reaction of 1,10-phenanthroline with cupric chloride in the mixed solution of methanol and ethanol and was characterized by infrared spectroscopy,thermogravimetric analysis,and temperature-programmed reduction.Their catalytic performance for the oxidative carbonylation of methanol to dimethyl carbonate（DMC） was investigated.The results showed that Cu（phen）Cl2 had the high thermal stability and exhibited the high catalytic performance due to the effect of the σ-π coordination bond between phen and Cu（Ⅱ）.The turnover number（TON） could reach 51.5 mol of DMC per mol of Cu,under the conditions of reaction temperature 150 ℃,total pressure 4.0 MPa,p（CO）/p（O2） = 19（below the explosion limit of CO） and the catalyst concentration in methanol 0.011 mol/L.It was also found that there was an induction period at the early reaction stage,and the change of TON was the ＂M＂ type with the increase of temperature.Further,a novel reaction mechanism was suggested.