IMPROVED PROCESS FOR THE SYNTHESIS OF 2,6-DICHLORO-5-FLUORONICOTINIC ACID AND 2,6-DICHLORO-5-FLUORONICOTINOYL CHLORIDE

摘要

An improved process for the preparation of 2,6-dichloro-5-fluoronicotinoylchloride is described where a 2,6-dihydroxy-5-fluoronicotinic acid ester is converted in one step using phosphorusoxychloride and a lithium reagent to 2,6-dichloro-5-fluor-onicotinoyl chloride and subsequent basic hydrolysis affords 2,6-dichloro-5-fluoronicotinic acid.