反应详情

A mixture of tert-butyl 3-(1-methyl-1H-pyrazol-5-yl)-pyrrolidine-1-carboxylate (2.3 g, 7.0 mmol) and NBS (1.48 g, 8.39 mmol) in THF (50 mL) was stirred at room temperature for 1 h. Solvent was removed to afford the crude product, which was purified by reverse phase Combiflash eluting with a 0-70% gradient of CH3CN in 0.3% NH4HCO3 to give tert-butyl 3-(4-bromo-1-methyl-1H-pyrazol-5-yl)pyrrolidine-1-carboxylate (2.28 g, 75% yield) as white solid. LCMS (ESI) m/z: 332.1 [M+H+]. 1H-NMR (500 MHz, CDCl3) δ 7.38 (s, 1H), 3.88 (s, 3H), 3.75-3.61 (m, 3H), 3.52 (s, 1H), 3.38 (s, 1H), 2.48 (s, 1H), 2.15 (s, 1H), 1.48 (s, 9H).

1. customSolvent was removed
2. customto afford the crude product, which
3. customwas purified by reverse phase Combiflash
4. washeluting with a 0-70% gradient of CH3CN in 0.3% NH4HCO3