反应详情

Palladium acetate (215 mg, 0.957 mmol) was added to tert-butyl[4-bromo-1H-pyrazol-1-yl]acetate (5 g, 19.14 mmol) (see Preparation 86), cyclopropyl boronic acid (8.22 g, 95.74 mmol), potassium phosphate (8.12 g, 38.29 mmol) and tricyclohexylphosphine (537 mg, 1.91 mmol) in toluene: water (60 mL:15 mL). The mixture was degassed for 20 minutes then refluxed for 18 hours. The reaction mixture was filtered through Celite™, the filtrate was evaporated in vacuo and the residue was purified by column chromatography on silica gel (gradient of EtOAc:hexane 15:85) to afford the title compound as an off white solid in 21% yield, 1.3 g.

1. customThe mixture was degassed for 20 minutes
2. temperaturethen refluxed for 18 hours
3. filtrationThe reaction mixture was filtered through Celite™
4. customthe filtrate was evaporated in vacuo
5. customthe residue was purified by column chromatography on silica gel (gradient of EtOAc:hexane 15:85)