Improved Process For The Synthesis Of 2-thiophene Acetic Acid And Its Derivatives

2-thiophene derivatives are widely used in pharmaceutical, pesticide, dye, chemical reagents and polymer additives. Including 2-chloromethyl-thiophene, thiophen-2yl-acetonitrile, thiophen-2-yl-acetic acid, thiophen-2-yl-acetyl chloride, 2-thiophen-2-yl-eacetamide,2-acetylthiophene.This paper mainly studied the synthesis process of thiophen-2-yl-acetic acid, based on reading and analyzing the relevant literature, selecting and comparing two synthetic routes. One of them using thiophene as raw material, through chloromethylation, cyano substitution, hydrolysis reaction to obtain 2-thienyl acetic acid; the other also uses thiophene through acetylation, oxidation, reduction reaction process to manufacture target product. On this basis, this paper also studied the 2-thienyl acetic acid acyl chloride, amine solution reaction, and synthesize several 2-thienyl acetic acid derivatives.According to the molecular structure of target product and the guiding principles of the synthesis process of the chemical medicine intermediate, considered from the raw material is cheap and easy to get, the product yield is high, quality is good, the environmental is friendly, the operation is feasibility, etc., a suitable for industrialized production line has been made finally.Based on the proposed synthetic route, this paper focus on the following two aspects:1. Optimization of reaction conditions, including the catalyst, reagent selection, choice of solvent, raw material ratio, reaction time and temperature and feeding mode, etc., and the best reaction conditions have been determined.2. Optimized of the after treatment of reactions, including recycling unreacted reactant and solvent, separation and purification of products, etc., a set of suitable for industrialized production processing after has been established.In this paper, the reaction conditions have been optimized, and the production cost has been reduced, product yield and quality has been improved, all of above are Made beneficial exploration for the process of industrialization...