反应详情

温度

200 °C

A mixture of 4-bromo-5-tert-butyl-2-methyl-2H-pyrazole-3-carboxylic acid ethyl ester (1.00 g, 3.46 mmol) and CuCN (372 mg, 4.15 mmol) in NMP (10 mL) was stirred at 200° C. under microwave irradiation for 1 h. After cooling to room temperature, the mixture was treated with DCM (100 mL) and filtered through diatomaceous earth. The filtrate was concentrated in vacuo, and the residue was purified by flash chromatography on silica gel (0:100-10:90 EtOAc-hexanes) to yield the title compound as a white solid. 1H-NMR (400 MHz, CDCl3) δ: 4.45 (q, J=7.2 Hz, 2H), 4.14 (s, 3H), 1.45 (t, J=7.2 Hz, 3H), 1.43 (s, 9H). Mass Spectrum (LCMS, ESI pos.) Calculated For C12H17N3O2: 236.1 (M+H), Measured: 236.1.

1. temperatureAfter cooling to room temperature
2. filtrationfiltered through diatomaceous earth
3. concentrationThe filtrate was concentrated in vacuo
4. customthe residue was purified by flash chromatography on silica gel (0:100-10:90 EtOAc-hexanes)