Hydrochloric Acid → 6-Chloro-2-methoxy-4-methylpyridine-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a suspension of 9.3 g (231 mmol, 60% w/w in mineral oil) NaH in THF (200 ml) was added a solution of 3.8 ml (93 mmol) Methanol in THF (200 ml) while the temperature was kept at 10-20° C. Subsequently a solution of 20.0 g (97 mmol) of 2,6-dichloro-4-methyl-pyridine-3-carboxylic acid in THF (200 ml) was added and the RM was heated to 70° C. for 16 h. After cooling to RT the mixture was acidified with a 2M aq. HCl to pH 3-4 and was then extracted with EtOAc (2×600 ml). The combined organic layers were washed with water and brine, dried over MgSO4 and concentrated in vacuo. The obtained crude 22.6 g 6-chloro-2-methoxy-4-methyl-pyridine-3-carboxylic acid was used in subsequent reactions without further purification.

Provenance & Evidence