1-Boc-pyrazole-4-boronic acid pinacol ester

269410-08-4

24424-99-5

552846-17-0

4-Pyrazoleboronic acid pinacol ester (1.16 g, 6.0 mmol) and di-tert-butyl dicarbonate (1.58 g, 7.2 mmol) were used as raw materials and dissolved in dichloromethane (40 mL). A catalytic amount of 4-dimethylaminopyridine (102 mg, 0.84 mmol) was added and the reaction was stirred at room temperature for 4 hours. After completion of the reaction, water was added to the reaction system and extracted with ethyl acetate. The organic phase was washed with saturated aqueous sodium chloride solution and then the solvent was removed by rotary evaporation to give the crude product 1-Boc-pyrazole-4-boronic acid pinacol ester (1.5 g, 85% yield).