铌酸催化的苯甲醛与甲醇缩合反应

采用铌酸为催化剂,探索了该催化剂对苯甲醛与甲醇缩合反应的影响.优化反应条件是,催化剂用量为反应物质的量的5mol%,甲醇10mL(兼作溶剂),回流状态下反应2h,反应的产率和转化率分别达到94%、98.0%.该催化剂同样适用于其他醛(酮)与甲醇的缩合反应,可得到34%～89%的产率.所述方法操作简单、产率高、选择性好而且对环境友好,反应结束后,催化剂很容易回收,并能有效重复使用.

Condensation of Benzaldehyde and Methanol Catalyzed by Niobic Acid

A catalytic system used for the condensation of aldehydes and methanol was developed, in which, niobic acid was used as catalyst and excess methanol was used as the condensation solvent. The condensation of benzaldehyde and methanol was studied as a probe, it was found that, 94% yield was obtained with 98.0% conversion under optimum conditions. The catalyst can be easily recovered and reused six times without noticeable decrease of the catalytic activity. This catalytic system can be applied to the condensation for a wide range of aldehydes with the yields from 34 % to 89 % .