Step 1: To a solution of 4-nitro-1H-pyrazole (100 g, 0.88 mol) in acetonitrile (ACN, 2 L) was added potassium carbonate (K2CO3, 183.2 g, 1.33 mol) and methyl chloroacetate (95.6 g, 0.88 mol). The reaction mixture was heated to 60 °C and the reaction was stirred at this temperature for 5 hours. Upon completion of the reaction, the mixture was filtered to remove insoluble solids and the solvent was subsequently removed by distillation under reduced pressure to afford methyl 2-(4-nitro-1H-pyrazol-1-yl)acetate as a white solid (150 g, 92% yield). The product was characterized by 1H NMR (400 MHz, CDCl3): δ 8.28 (s, 1H), 8.11 (s, 1H), 4.98 (s, 2H), 3.84 (s, 3H).
