Sodium hydride → N,N-Dimethyl-2-(3-methyl-4-nitro-pyrazol-1-yl)-acetamide

Participants

Reaction Steps

To a solution of 3-methyl-4-nitropyrazole (Apollo, Cheshire, UK, 500 mg, 3.93 mmol) in DMF (10 ml) was added 55% NaH in oil (198 mg, 4.54 mmol) and the reaction mixture was stirred for 30 min at rt. Then to the reaction mixture was added a solution of 2-bromo-N,N-dimethylacetamide (stage L.3, 720 mg, 4.34 mmol) in DMF (3 ml). The reaction mixture was stirred for 1 h at it then quenched with saturated aqueous NaHCO3 and extracted with EtOAc (2×). The combined organic layers were washed with water (2×), brine, dried over Na2SO4, filtered and evaporated. The crude product was purified by Prep. HPLC (H2O (0.1% TFA)/CH3CN 97:2 to 75:25; reverse phase silica gel). The fractions containing product were collected together, basified with NaHCO3 and concentrated before being extracted with EtOAc (3×). The combined organic layers were washed with brine, dried over Na2SO4, filtered and evaporated to give the title compound as a white solid (HPLC tR 2.06 min (Method A); M+H=213 MS-ES).

Provenance & Evidence