乙基香兰素合成工艺改进

Improvement in Synthesization of Ethyl Vanillin

采用氯化溴法合成3-溴-4-羟基苯甲醛,再通过乙氧基化合成乙基香兰素。对反应温度、反应时间、原料配比、溴化剂的滴加速度、溶剂等影响中间体产率的因素进行了研究。在溴化阶段用氯化溴代替溴素,用氯仿作溶剂,乙酸乙酯作助溶剂,使一溴化物的产率提高了9.4%;在乙氧基化步骤中用CuO作催化剂,用乙醇和DMF作反应溶剂,对原料配比和催化剂用量做了研究,使得最终产物乙基香兰素的产率达到82.5%。

This article introduces the process in preparation of 3 - bromo - 4 - hydroxy ben- zaldehyde using bromine chloride, then made ethyl vanillin through ethoxylation. Influence of reac- tion temperature, reaction time, mole ratio of raw materials, brominating agent feeding speed and solvent on reaction were considered. On the stage of bromination, using bromine chloride instead of bromine, using trichloromethane as solvent, ethyl acetate as helpful solvent and the yield of monobromide has an increase of 9.4 percent. In the progress of ethoxylation, using CuO as catalysts, the mixture of ethanol and DMF as solvent, and made a study of mole ratio of raw materials and catalyst dosage . The yield rate of final products reach to 82.5 percent.