2-Bromopropane → HCID 19576680, compound

Participants

Reaction Conditions

Reaction Steps

3-Nitro-1H-pyrazole (prepared in example 3, 250 mg, 2.21 mmol) was dissolved in anhydrous N,N-dimethylformamide (5.5 mL) and a 60% dispersion of sodium hydride in mineral oil (97 mg, 2.43 mmol) was added while stirring under nitrogen. After the effervescence ceased and the reaction stirred for an additional 25 min, the reaction was chilled to 0° C. and 2-bromo-propane (324 mg, 2.64 mmol) was added. The reaction continued to stir under nitrogen at 0° C. for 20 min. The ice bath was removed and the reaction continued to stir at 25° C. for 16 h. The reaction was diluted with ethyl acetate (100 mL), washed with water (2×50 mL), saturated aqueous brine solution (2×20 mL), dried over magnesium sulfate and concentrated in vacuo to give an oil. Purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 40 g; 0% ethyl acetate/hexanes to 20% ethyl acetate/hexanes) afforded 1-isopropyl-3-nitro-1H-pyrazole (146 mg, 43%) as a white waxy solid: H1-NMR (400 MHz, CDCl3) δ 1.58 (6H, d, J=6.8 Hz), 4.59 (1H, septet, J=6.4 Hz), 6.88 (1H, d, J=2.8 Hz), 7.47 (1H, d, J=2.0 Hz).

Provenance & Evidence