Water → 4-Chloro-5-hydroxypicolinic acid

Participants

Reaction Steps

By applying the reaction sequence of either esterification, Suzuki reaction, hydrogenation, saponification or esterification, Negishi reaction and saponification, a commercially available compound of Structure 32 may be transformed into a compound of Structure 33. The compounds of Structure 32 may be prepared, for instance, by reacting 4,5-dichloro-picolinic acid with water in their presence of an acid (Lit.: e.g. J. Prakt. Chem.; 27 (1883), 293) to give 4-chloro-5-hydroxy-picolinic acid. This compound may then be alkylated in analogy to literature procedures (T. Vermonden; D. Branowska; A. T. M. Marcelis; E. J. R. Sudholter; Tetrahedron 59 (2003), 5039-5045) to give 4-chloro-5-methoxy picolinic acid methyl ester which can be hydrolysed under acidic or basic conditions to the desired compound of Structure 32.

Provenance & Evidence