Sodium Hydroxide → 5-(Difluoromethyl)pyridine-2-carboxylic acid

Participants

Reaction Steps

A solution of 5-difluoromethyl-pyridine-2-carboxylic acid methyl ester (700 mg, 3.7 mmol) in ethanol (8.0 ml) was treated with a solution of sodium hydroxide (5M, 1.5 ml) at 0° C. Then the reaction mixture was allowed to attain room temperature and was stirred for 5 hours. For the workup, ethanol was removed at reduced pressure. The resulting solid was dissolved in water (5 ml) and the solution was washed with ethyl acetate (2×5 ml). The aqueous layer acidified with a solution of citric acid (10%, pH˜4), followed by extraction with a 7:3-mixture of dichloromethane and methanol (5×10 ml). The combined organic layers were washed with brine (20 ml), dried over sodium sulphate, and evaporated at reduced pressure. The 5-difluoromethyl-pyridine-2-carboxylic acid was obtained as a white solid (400 mg, 62% of theory).

Provenance & Evidence