反应详情

温度

90 °C

A solution of 3-nitro-1H-pyrazole (prepared as in Example 5, 12.0 g, 106 mmol) in N,N-dimethylformamide (150 mL) was treated with para-toluenesulfonic acid (S)-2,2-dimethyl-[1,3]dioxolan-4-yl-methyl ester (25.5 g, 89.0 mmol), and potassium carbonate (24.5 g, 178 mmol). The reaction mixture was heated to 90° C. for 6 h under nitrogen. After this time, the reaction mixture was diluted with ethyl acetate, washed with water and a saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, rinsed and concentrated in vacuo. Purification by ISCO flash chromatography (128 g, 5-30% ethyl acetate/hexanes) afforded 1-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl-methyl)-3-nitro-1H-pyrazole (14.5 g, 73%) as a light yellow oil.

1. washwashed with water
2. dry with materiala saturated aqueous sodium chloride solution, dried over sodium sulfate
3. filtrationfiltered
4. washrinsed
5. concentrationconcentrated in vacuo
6. customPurification by ISCO flash chromatography (128 g, 5-30% ethyl acetate/hexanes)