p-Toluenesulfonic acid → N-[3-[5-chloro-2-(difluoromethoxy)phenyl]-1-[2-oxo-2-(4-oxo-1-piperidyl)ethyl]pyrazol-4-yl]pyrazolo[1,5-a]pyrimidine-3-carboxamide

Participants

Reaction Steps

To a solution of N-[3-[5-chloro-2-(difluoromethoxy)phenyl]-1-[2-(1,4-dioxa-8-azaspiro[4,5]decan-8-yl)-2-oxo-ethyl]pyrazol-4-yl]pyrazolo[1,5-a]pyrimidine-3-carboxamide (1.01 g, 1.72 mmol) in acetone (20 mL) was added p-toluenesulfonic acid (359 mg, 2.06 mmol) and refluxed for 6 hours. LC/MS (method 31) shows product and presence of minor amounts of starting material. The reaction was cooled to room temperature and quenched with water. This was then extracted with ethyl acetate, dried with solid anhydrous magnesium sulfate powder and filtered to give a red oil. This was then purified by ISCO with a silica column and eluted with 0-15% methanol in dichloromethane to afford 0.43 g (0.78 mmol) of N-[3-[5-chloro-2-(difluoromethoxy)phenyl]-1-[2-oxo-2-(4-oxo-1-piperidyl)ethyl]pyrazol-4-yl]pyrazolo[1,5-a]pyrimidine-3-carboxamide as a foamy off white solid. LC/MS (method 39) [M+H]+=544.1, RT=1.91 min.

Provenance & Evidence