反应详情

温度

100 °C

A solution of 3-nitro-1H-pyrazole (prepared in Example 3, 200 mg, 1.77 mmol) in N,N-dimethylformamide (5 mL) was treated with solid potassium carbonate (352 mg, 2.55 mmol) and 2,2-dimethyl-oxirane (314 mL, 3.54 mmol) and placed in a sealed tube and heated to 100° C. for 1 h in an oil bath. After this time the reaction was cooled to 25° C. and diluted with water (10 mL) and extracted with ethyl acetate (3×10 mL). The organic layers were then combined and dried over sodium sulfate, filtered and concentrated in vacuo. Purification by AnaLogix Intelliflash system (12 g column, 50% ethyl acetate/hexanes to 60% ethyl acetate/hexanes) afforded 2-methyl-1-(3-nitro-pyrazol-1-yl)-propan-2-ol (175 mg, 54%) as a clear colorless oil: ES-HRMS m/e calcd for C7H11N3O3 (M+H)+ 186.0873, observed 186.0873; 1H NMR (300 MHz, CDCl3) δ ppm 1.25 (s, 6H, 2×CH3), 2.11 (br. s., 1H, OH), 4.18 (s, 2H, NCH2), 6.92 (d, J=2.4 Hz, 1H, Ar), 7.60 (d, J=2.4 Hz, 1H, Ar).

1. customplaced in a sealed tube
2. temperatureAfter this time the reaction was cooled to 25° C.
3. extractionextracted with ethyl acetate (3×10 mL)
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customPurification by AnaLogix Intelliflash system (12 g column, 50% ethyl acetate/hexanes to 60% ethyl acetate/hexanes)