A Pd/C reduction method adopting water as a solvent for preparing indole-2-carboxylic acid

• Main Author: WEI XIAOWU
• Format: Patent
• Language: Chinese; English
• Published: 08.02.2017
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

The invention relates to a Pd/C reduction method adopting water as a solvent for preparing indole-2-carboxylic acid. Ethyl 2-nitrophenyl pyruvate is subjected to hydrogenation reduction cyclization in a high-pressure reaction kettle by adopting water as the solvent and adopting Pd/C as a catalyst, the Pd/C is recovered by filtering, and a filtrate is subjected to distillation, acidity adjustment and crystallization to obtain the indole-2-carboxylic acid. The catalyst is easily available and low in cost and can be repeatedly used. According to the method, the raw material can be easily recovered, post-treatment operation is simple, environment pollution is low, reaction operation safety is high, a reaction yield is high, and product quality is good, thus facilitating industrialization. 本发明涉及种水做溶剂钯炭还原法制备吲哚-2-甲酸，邻硝基苯丙酮酸乙酯以水做溶剂在高压反应釜中，钯炭为催化剂进行加氢还原环化，过滤回收钯炭催化剂，滤液蒸馏、调酸、析晶，得到吲哚-2-甲酸。本发明催化剂易得，成本低，催化剂可以重复使用，原料易回收，后处理操做简单，环境污染小，反应操做安全性高，反应收率高，产品质量好，利于工业化。