To a solution of (S)-2-(4-phenoxyphenyl)-7-(piperidin-4-yl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-3-carboxamide (417 mg, 1 mmol) in DCM (20 mL) was added NaHCO3 (168 mg, 2 mmol) and water (5 mL), followed by BrCN (127 mg, 1.2 mmol). The mixture was stirred at RT for 16 h. To the mixture was added DCM (50 mL) and brine (20 mL). The organic phase was further washed with brine (100 mL), dried over Na2SO4. Concentrated and purified by Pre-TLC (DCM/MeOH, 50/1) to afford 330 mg (75%) of white solid. MS (ESI) m/e [M+1]+ 443.0.
