Cesium carbonate → HCID 118522632, compound

Participants

Reaction Steps

A solution of tert-butyl (3-((3-(5-chloro-2-(difluoromethoxy)phenyl)-1H-pyrazol-4-yl)carbamoyl)pyrazolo[1,5-a]pyrimidin-2-yl)carbamate (1.0 g, 1.92 mmol) in DMF (10 mL) was treated with cesium carbonate (0.69 g, 2.12 mmol) and tert-butyl-bromoacetate (0.43 g, 2.12 mmol) and was left to stir at room temperature for 2.5 hours. The reaction mixture was diluted with water and the resultant precipitate was collected by filtration. The resultant solid was purified by flash chromatography on silica eluting with 0-70% EtOAc in cyclohexane. Appropriate fractions were combined and evaporated to afford [4-[(2-tert-butoxycarbonylamino-pyrazolo[1,5-a]pyrimidine-3-carbonyl)-amino]-3-(5-chloro-2-difluoromethoxy-phenyl)-pyrazol-1-yl]-acetic acid tert-butyl ester as a white solid (0.91 g, 74%). LCMS (Method 3) [M+H]+=633.9, RT=4.46 min. 1H NMR (400 MHz, CDCl3) δ: (ppm) 9.78 (s, 1H), 9.70 (s, 1H), 8.76 (dd, 1H, J=1.8, 6.8 Hz), 8.47 (dd, 1H, J=1.8, 4.3 Hz), 8.34 (s, 1H), 7.69 (d, 1H, J=2.5 Hz), 7.41 (dd, 1H, J=2.7, 8.7 Hz), 7.28 (d, 1H, J=8.8 Hz), 6.92 (dd, 1H, J=4.4, 6.9 Hz), 6.47 (t, 1H, J=74.0 Hz), 4.85 (s, 2H), 1.56 (s, 9H), 1.49 (s, 9H).

Provenance & Evidence