METHOD FOR PREPARING CHLORINE-SUBSTITUTED PHENOXYACETIC ACID ESTERS (VARIANTS) Russian patent published in 2008 - IPC C07C69/62 C07C67/08 

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for synthesis of chlorine-substituted phenoxyacetic acid esters by the esterification reaction of corresponding acid with (C₇-C₉)-alcohol of normal structure of isomers, or in the combination. The esterification reaction is carried out in the mole ratio alcohol : acid = (1.1-1.75):1.0 by step-by-step increasing the temperature process. At the first step the process is carried out at the boiling point of azeotrope alcohol : water depending on the residual pressure value generated in the system for separation of the main mass of formed reaction water followed by increasing temperature by 20-60°C for the complete termination of the esterification reaction. The process can be carried out in the presence of catalytic amounts of mineral acids 0.01-0.03 wt.-% of the reaction mass. Invention provides high quality and high yield of the end product.

EFFECT: improved method of synthesis.