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. Application In Synthesis of 4-Nitro-1H-pyrazole-3-carboxylic acid
4-Nitropyrazoie-3-carboxylic acid (10 g; 63.66 mmol) was added to a stirred solution of 4-fluoroaniline (6.7 ml; 70 mmol), EDC (14.6 g; 76.4 mmol), and HOBt (10.3 g; 76.4 mmol) in DMF (25 ml), then stirred at room temperature overnight. The solvent was removed by evaporation under reduced pressure and the residue triturated with ethyl acetate / saturated brine solution. The resultant yellow solid was collected by filtration, washed with 2M hydrochloric acid, then dried under vacuum to give 15.5 g of the title compound. (LC/MS: Rt 2.92 [M+H]+ 250.89 ).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5334-40-7, its application will become more common.
Reference:
Patent; ASTEX THERAPEUTICS LIMITED; WO2006/77424; (2006); A1;; ; Patent; ASTEX THERAPEUTICS LIMITED; WO2006/77425; (2006); A1;,
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