Diisopropylethylamine → 2-Nitro-5-(oxetan-3-yl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine

Participants

Reaction Steps

To a solution of 1-(2-bromoethyl)-5-(bromomethyl)-3-nitro-1H-pyrazole (500 mg, 1.6 mmol) in acetonitrile (20 mL) was added oxetan-3-amine (140 mg, 1.92 mmol) and diisopropylethyl amine (372 mg, 0.50 ml, 2.88 mmol) drop wise and the resulting mixture was stirred at room temperature for 24 h. The solution was concentrated and the residue dissolved in ethyl acetate (50 mL), washed with water (50 mL) and dried over magnesium sulfate. The resulting mixture was filtered and evaporated and the residue purified by flash chromatography (SF25-40 g, 50% to 100% ethyl acetate in hexanes) to give 2-nitro-5-oxetan-3-yl-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine (255 mg, 71%) as a light yellow solid.

Provenance & Evidence