Water → 5-Cyano-3-methylpyridine-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To the stirred solution of 5-cyano-3-methylpyridine-2-carboxylic acid tert-butyl ester (20.7 g, 94.9 mmol) in toluene (200 mL) was added H2O (3.4 mL) at ambient temperature. The mixture was then cooled to 0˜5° C. with stirring, at this point, TFA (200 mL) was added to the mixture slowly while maintaining the reaction temperature at 25˜35° C. The reaction mixture was then heated at 33° C. with stirring. After 60 min, to the reaction mixture was added toluene and the mixture was concentrated in vacuo to ˜¼ of the original volume to remove TFA by azeotropic distillation with toluene. To the concentrated mixture was added toluene and the mixture was evaporated in vacuo to ˜¼ of the original volume. The same evaporation manipulation was repeated once and the precipitated product was collected by filtration. The filter cake was washed with toluene and dried in vacuum oven at 50° C. for 8 h to give the title compound as a pale yellow crystalline solid: ESIMS: 163; [(M+H)+]; 1H NMR (400 MHz, DMSO-d6): δ 8.90 (s, 1H), 8.35 (s, 1H), 2.46 (s, 3H).

Provenance & Evidence