632365-54-9, name is Methyl 5-amino-1H-pyrazole-3-carboxylate, belongs to pyrazoles-derivatives compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Product Details of 632365-54-9
5-Amino-3-pyrazolcarboxylic acid methyl ester (16.91 g, 119.8 mmol) is dissolved in ethanol (2.4 L) and hydrochloric acid (37%, 12.5 mL, 150 mmol) is added. Then, a solution of 2-bromo-malonealdehyde (18.9 g, 125.2 mmol) is dissolved in ethanol (1.4 L) and is quickly added in a drop wise manner at RT. After 30 min, a precipitation is observed; after 6 hours the precipitate is removed and washed with 50 ml ethanol and thereafter with 50 ml diethyl ether. Here, 4.19 g of the clean product are isolated. After evaporation of the filtrate and crystallisation, additional 1.43 g product are obtained to yield 6-Bromo-pyrazolo[1,5-a]pyrimidine-2-carboxylic acid methyl ester (5.62 g, 18.3% d. Th.). In case of a smaller scale reaction with only 1 g of the starting amine 5-amino-3-pyrazolcarboxylic acid methyl ester, the yield is much better e.g. 68%.
The synthetic route of 632365-54-9 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; MERZ PHARMA GMBH & CO. KGAA; US2008/32998; (2008); A1;,
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