Synthetic Pathway of [2,4-Dichloro-6-(3,5-dichloro-2-hydroxy­benzamido)phenoxy]acetic Acid

Synthetic route of 3,5-dichlorosalicylic acid anilide containing the carboxymethoxy group in the aniline fragment in ortho-position to amide group has been suggested. The obtained intermediate (2,4-dichloro-6-nitrophenoxy)-N,N-dimethylacetamide has been reduced into the amine and acylated with 3,5-dichloro-2-hydroxybenzoyl chloride, and then protective N,N-dimethylamide group has been selectively hydrolyzed in an alkaline medium. Without protection of the carboxyl group, the reaction with 3,5-dichloro-2-hydroxybenzoyl chloride has afforded mainly 6,8-dichloro-2H-1,4-benzoxazin-3(4H)-one.