1,2-Dibromoethane → N-[1-(2-bromoethyl)-3-[5-chloro-2-(difluoromethoxy) phenyl]-1H-pyrazol-4-yl]pyrazolo[1,5-a]pyrimidine-3-carboxamide

Participants

Reaction Conditions

Reaction Steps

A mixture of N-[3-[5-chloro-2-(difluoromethoxy)phenyl]-1H-pyrazol-4-yl]pyrazolo[1,5-a]pyrimidine-3-carboxamide (3.00 g, 7.41 mmol), Cs2CO3 (9.90 g, 30.38 mmol), tetrahydrofuran (90 mL), 1,2-dibromoethane (7.00 g, 37.26 mmol) was stirred at 70° C. for 3 hours in an oil bath. The mixture was allowed to cool to ambient temperature then concentrated under reduced pressure. The residue was purified by flash chromatography on silica eluting with ethyl acetate/petroleum ether (1:1) to afford N-[1-(2-bromoethyl)-3-[5-chloro-2-(difluoromethoxy)phenyl]-1H-pyrazol-4-yl]pyrazolo[1,5-a]-pyrimidine-3-carboxamide as a off-white solid (2.2 g, 58%). TLC: Rf=0.6; ethyl acetate/petroleum ether=1:1; LCMS (Method 14) [M+H]+=513.2, RT=1.03 min.

Provenance & Evidence