Improved Process for the Synthesis of 2,6-Dichloro-5-Fluoronicotinic Acid and 2, 2,6-Dichloro-5-fluoronicotinic acid and 2,6-dichloro-5-fluoronicotinoyl chloride , 6-Dichloro-5-Fluoronicotinoyl Chloride)

摘要

The present invention provides an improved process for the preparation of 2,6-dichloro-5-fluoronicotinoyl chloride from 2,6-dihydroxy-5-fluoronicotinic acid ester using phosphorus oxychloride and lithium reagents in the first step. It is about.