Application of 5334-40-7,Some common heterocyclic compound, 5334-40-7, name is 4-Nitro-1H-pyrazole-3-carboxylic acid, molecular formula is C4H3N3O4, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
A) Methyl 1-methyl-4-nitro-1H-pyrazole-5-carboxylate To a suspension of 4-nitro-1H-pyrazole-3-carboxylic acid (37 g) and potassium carbonate (97.6 g) in DMF (600 mL), dimethyl sulfate (71.2 g) was added dropwise under ice cooling, and the mixture was stirred at room temperature for 16 hours. The reaction mixture was poured to water, followed by extraction with ethyl acetate. The extract was dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/petroleum ether) to obtain the title compound (8.62 g). 1H NMR (400 MHz, CDCl3) delta 4.02 (3H, s), 4.03 (3H, s), 8.01 (1H, s).
The synthetic route of 5334-40-7 has been constantly updated, and we look forward to future research findings.