Tolfenamic acid synthesis
- Product Name:Tolfenamic acid
- CAS Number:13710-19-5
- Molecular formula:C14H12ClNO2
- Molecular Weight:261.7
Yield:13710-19-5 88.6%
Reaction Conditions:
Stage #1:ortho-chlorobenzoic acid with sodium hydroxide for 1 h;Reflux;
Stage #2:3-chloro-2-methylbenzenamine with aluminum oxide;sodium hydroxide for 3 h;Reflux;
Steps:
2 Example 2
100 g of o-chlorobenzoic acid and 25 g of sodium hydroxide were weighed into 500 mL of methyl isobutyl ketone and heated to refluxReaction 1 h.90 g of 3-chloro-2-methylaniline and 50 g of alumina-supported sodium hydroxide were weighed into a solution ofThe reaction mixture was heated and refluxed for 3 h, then cooled and added with 500 mL of water. The aqueous phase was acidified with concentrated hydrochloric acid until the pH was 2-3, and the mixture was stirred for lh to crystallize and filter. And the crude tosylate was recrystallized from ethanol / water mixed solvent to obtain 158.2 g of the refined product of Tofenamic Acid. The yield was 88.6%.
References:
Danyang Hengan Chemical Technology Research Institute Co., Ltd;Chen, Guoping;Xia, Fangfang;Du, chengming;Chen, Liqing;Wang, Xia;Zhang, Liang;Wang, Taoying;Jing, Jiren;Xia, Xinkai;Wang, Haida CN104557584, 2016, B Location in patent:Paragraph 0016; 0017; 0018