邻乙氧基苯甲酸的合成

Synthesis of O-ethoxy Benzoic Acid

摘要:

对以水杨酸甲酯为原料制取西地那非重要中间体邻乙氧基苯甲酸的合成工艺进行了改进，先制得水杨酸甲酯钠盐，经干燥后与溴乙烷乙基化得到邻乙氧基苯甲酸甲酯，然后将邻乙氧基苯甲酸甲酯水解制得邻乙氧基苯甲酸。产品纯度为99.88%(HPLC法)，总收率为89.5%。该工艺已在重庆康尔威药业股份有限公司中试。

Abstract:

The preparation process for o-ethoxy benzoic acid, a key intermediate for sildenafil, was improved with methylsalicylate. Sodium salt of methylsalicylate was firstly prepared and treated with ethyl bromide to give methyl o-ethoxybenzoate, which was hydrolyzed to afford o-ethoxy benzoic acid (HPLC purity 99.88%). The overall yield was 89.5% and It has been produced in Chongqing Kangerwei phamaceutical Co. Ltd.