The reaction was carried out overnight at 70 °C in acetonitrile (10 mL) in the presence of sodium iodide (39 mg, 0.26 mmol) and potassium carbonate (1.0 g, 7.8 mmol) using pinacol ester of 4-pyrazoleboronic acid (0.50 g, 2.58 mmol) and bromoacetonitrile (1.3 g, 10.8 mmol). Upon completion of the reaction, the reaction was quenched by the addition of water and extracted with ethyl acetate (3 x 10 mL). The organic phases were combined, dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by silica gel column chromatography (eluent: 10% to 100% ethyl acetate/hexane gradient elution) to afford 2-(4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazol-1-yl)acetonitrile (0.38 g, 63% yield). Mass spectrum (ESI) m/z: 234.1 (M+H+).
