Acetic Acid → HCID 66646088, compound

Participants

Reaction Steps

To a mixture of 5-methyl-3-(pyridin-2-yl)isoxazole-4-carbaldehyde (811 mg, 4.31 mmol) and 5-amino-2-methyl-2H-pyrazole-3-carboxylic acid ethyl ester hydrochloride (886 mg, 4.31 mmol) in MeOH (36 mL) was added molecular sieves (1.3 g). The reaction mixture was stirred at RT for 1 h. Then acetic acid (3.45 mL, 60.3 mmol) was added. After stirring for additional 5 min, sodium cyanoborohydride (542 mg, 8.62 mmol) was added in portions over 2 min and the reaction mixture was stirred at RT for 30 min, then evaporated. The residue was extracted with dichloromethane and then washed with a saturated solution of sodium hydrogen carbonate. The organic layers were washed with water and brine, dried over sodium sulfate and evaporated. Purification by chromatography (silica, dichloromethane) afforded the title compound as a white solid (814 mg, 55%). MS: m/e=342.1 [M+H]+.

Provenance & Evidence