In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 1621-91-6 as follows. Formula: C4H4N2O2
b) Methyl lH-pyrazole-3-carboxylate lH-Pyrazole-3-carboxylic acid (15 g, 133.8 mmol) was dissolved in MeOH (250 ml). Concentrated H2S04 (30 ml) was added to the solution. The resulting mixture was refluxed for 12 h and concentrated. The residue obtained was quenched by saturated aqueous solution of NaHC03 and extracted with EtOAc. The organic layer was concentrated. Yield 12.05 g. 1H-NMR (400 MHz; CDC13): delta 3.98 (s, 3H), 6.86 (d, 1H), 7.85 (d, 1H), 1 1.9 (bs, 1H).
According to the analysis of related databases, 1621-91-6, the application of this compound in the production field has become more and more popular.
Reference:
Patent; ORION CORPORATION; TOeRMAeKANGAS, Olli; WOHLFAHRT, Gerd; SALO, Harri; RAMASUBRAMANIAN, Rathna, Durga; PATRA, Pranab, Kumar; MARTIN, Arputharaj, Ebenezer; HEIKKINEN, Terhi; VESALAINEN, Anniina; MOILANEN, Anu; KARJALAINEN, Arja; WO2012/143599; (2012); A1;,
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