催化剂对碳酸二甲酯与苯酚酯交换反应的影响

Influences of Catalysts on the Transesterification of Dimethyl Carbonate and Phenol

研究了Lewis酸碱、钛酸酯和有机锡分别作催化剂对碳酸二甲酯 (DMC)与苯酚 (PhOH)酯交换反应的催化活性。在这些催化剂中 ,Pb(Ac0 ) 2 ·3H2 O、Ti(OBu) 4 和Bu2 SnO均具有较高的催化活性 ,并且无副产物苯甲醚生成 ,其中Bu2 SnO具有更高的催化活性。分别以Pb(Ac0 ) 2 ·3H2 O、Ti(OBu) 4 、Bu2 SnO为催化剂考察了物料配比、反应温度、催化剂用量和反应时间等条件对反应结果的影响。实验表明 ,当n(DMC)∶n(PhOH)∶n(Bu2 SnO) =2 0∶1 0∶0 0 3,反应温度 175℃ ,反应时间 14h时 ,苯酚的转化率达到 4 3 0 % ,生成MPC和DPC的选择性分别为 96 8%和 3 2 %。

The catalytcal behavior of a series catalysts, including Lewis acid and base, titanates and tin compounds in transesterification of phenol(PhOH) and dimethylcarbonate(DMC) have been investigated. It is found that Pb(AcO) 2·3H 2O and Ti(OBu) 4 exihibites higher activities, and the highest catalytic activity among above mentioned catalysts is Bu 2SnO. The effects of the ratio of reactants, amount of catalyst, reaction temperature and reaction time on the reaction were examined. It is found that at molar ratio of DMC∶PhOH∶Bu 2SnO=2.0∶1.0∶0.03, 175 ℃ and 14 h the conversion of phenol was 43.0%, with selectivity for methylphenyl carbonate, and diphenyl carbonate being 96.8% and 3.2%, respectively.