Cesium carbonate → methyl 1-methyl-4-nitro-1H-pyrazole-5-carboxylate

Participants

Reaction Steps

340 mg (1.99 mM) of 4-nitro-1H-pyrazole-3-carboxylic acid methyl ester was dissolved in 4 ml of N,N-dimethylformamide, to which 0.33 ml (2.19 mM) of iodomethane and 1.3 g (3.98 mM) of cesium carbonate were added dropwise, and the resulting mixture was stirred under a nitrogen atmosphere for 30 minutes. The solvent was distilled off under reduced pressure, and the resultant was extracted with ethyl acetate and brine. The organic solvent layer was dried over anhydrous sodium sulfate, filtered, and then distilled under reduced pressure. The resulting impure compound was purified by column chromatography (hexane:ethyl acetate=2:1), to obtain 110 mg (30%) of the title compound and 195 mg (53%) of the compound of Preparative Example 7.

Provenance & Evidence