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.
Thionyl chloride (2.90 ml, 39.8 mmol) was slowly added to a mixture of 4-nitro-3-pyrazolecarboxylic acid (5.68 g, 36.2 mmol) in EtOH (100 ml) at ambient temperature and the mixture stirred for 48 h. The mixture was reduced in vacuo and dried through azeotrope with toluene to afford 4-nitro-1H-pyrazole-3-carboxylic acid ethyl ester as a white solid (6.42 g, 96%). (1H NMR (400 MHz, DMSO-d6) D 14.4 (s, 1 H), 9.0 (s, 1 H), 4.4 (q, 2H), 1.3 (t, 3H)).
The synthetic route of 5334-40-7 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; ASTEX THERAPEUTICS LIMITED; WO2006/77424; (2006); A1;; ; Patent; ASTEX THERAPEUTICS LIMITED; WO2006/77425; (2006); A1;,
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