Acetic Acid → (R)-ethyl 5-(2-(5-fluoro-2-oxo-1,2-dihydropyridin-3-yl)pyrrolidin-1-yl)pyrazolo[1,5-a]pyrimidine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a mixture of (R)-ethyl 5-(2-(5-fluoro-2-methoxypyridin-3-yl)pyrrolidin-1-yl)pyrazolo[1,5-a]pyrimidine-3-carboxylate (1.0 g, 2.60 mmol, Preparation K, Step A) and AcOH (7.44 mL, 130 mmol) was added HBr (4.76 mL, 33 wt % in acetic acid, 26 mmol) at ambient temperature. The reaction mixture was heated at 90° C. for 2 hours. After cooling, the reaction mixture was diluted with EtOAc, washed with water, saturated NaHCO3, and brine, dried with MgSO4, filtered and concentrated. The crude material was purified by silica column chromatography, eluting with 2-3% MeOH/DCM to yield the title product (0.73 g, 76%). MS (apci) m/z=372.0 (M+H).

Provenance & Evidence