5334-40-7, name is 4-Nitro-1H-pyrazole-3-carboxylic acid, 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. SDS of cas: 5334-40-7
Step 1: Into a 250 mL round bottom flask containing a suspension of 4-nitro-1H-pyrazole-3- carboxylic acid (20.0 g, 127 mmol) in methanol (100 mL) was added concentrated sulfuric acid(4 mL) dropwise over 5 mm at 0 C and the resulting slurry was refluxed at 80 C for 16 h. The solvent was removed under reduced pressure and the residual mass was dissolved in ethyl acetate (300 mL) and washed with saturated aqueous sodium bicarbonate solution (2 x 100 mL) and brine (100 mL) and dried over anhydrous sodium sulfate. The solution was filtered and concentrated under reduced pressure to give methyl 4-nitro-1H-pyrazole-3-carboxylate as asolid. The crude product was taken to the next step without further purification. MS calc?d [MHj 170.0, found 170.0.
The synthetic route of 5334-40-7 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; MERCK SHARP & DOHME CORP.; LIM, Jongwon; ALTMAN, Michael, D.; BRUBAKER, Jason, D.; GIBEAU, Craig, R.; (107 pag.)WO2016/144848; (2016); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics