Triethylamine → 1-propyl-5-(tetrahydro-2H-pyran-4-ylmethyl)-1H-pyrazole-3-carbonitrile

Participants

Reaction Steps

A solution of trifluoroacetic anhydride (2.50 mL, 17.7 mmol) in dichloromethane (32 mL) was added over a period of ten minutes to a 0° C. solution of 1-propyl-5-(tetrahydro-2H-pyran-4-ylmethyl)-1H-pyrazole-3-carboxamide (4.05 g, 16.1 mmol) and triethylamine (4.89 g, 48.3 mmol) in dichloromethane (32 mL). After the addition was complete, the cooling bath was removed and the solution was stirred for three hours. The solution was washed with 2 M aqueous sodium carbonate. The aqueous layer was extracted three times with tert-butyl methyl ether. The organic layers were combined, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by automated flash chromatography (eluting with 40% to 70% ethyl acetate in hexane) to provide 3.98 g of 1-propyl-5-(tetrahydro-2H-pyran-4-ylmethyl)-1H-pyrazole-3-carbonitrile as a pale yellow oil.

Provenance & Evidence