Cesium carbonate → 5-ethyl-1-(2-methoxyethyl)-4-nitro-1H-pyrazole-3-carboxamide

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-ethyl-4-nitro-1H-pyrazole-5-carboxamide (1.62 g, 8.80 mmol, prepared using procedure in WO9849166), 2-bromoethyl methyl ether (1.23 g, 8.85 mmol) and cesium carbonate (2.90 g, 8.92 mmol) in N,N-dimethylformamide (20 ml) was stirred at 20° C. for 20 h. The reaction mixture was concentrated in vacuo and the residue was partitioned between EtOAc (125 ml) and brine (100 ml). The phases were separated, and the organic layer was dried (Na2SO4), filtered and concentrated in vacuo. The crude product was purified by column chromatography (EtOAc/MeOH, 97:3) to afford the title compound of preparation 4 (831 mg, 3.43 mmol, 39%).

Provenance & Evidence