Potassium Carbonate → 1-((R)-2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-3-nitro-1H-pyrazole

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence