Synthesis of 6-aryl-4-aminopicolinates and 2-aryl-6-aminopyrimidine-4-carboxylates by direct Suzuki coupling

摘要

Arylalkyl and alkyl 4-amino-3-chloro-6- (4-chloro-2-fluoro-3-methoxyphenyl) pyridine-2-carboxylate, and arylalkyl and alkyl 4-amino-3-chloro-5- An improved method of synthesizing 6-aryl-4-aminopicolinates, such as fluoro-6- (4-chloro-2-fluoro-3-methoxyphenyl) pyridine-2-carboxylate, is described herein. Ru. The improved method includes a direct Suzuki coupling step, which eliminates the protection / deprotection steps of current chemical processes, thus eliminating or reducing various raw materials, equipment and cycle times, and , Use of crude AP, use of ABA-diMe, and other process conditions including changes in pH, catalyst concentration, solvent composition, and / or work procedures. The present invention has been extended to include the synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.