These common heterocyclic compound, 42098-25-9, name is 5-Chloro-1-methyl-4-nitro-1H-pyrazole, its 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. COA of Formula: C4H4ClN3O2
KO’Bu (938 mg, 8.36 mmol) was added to a stirred solution of 5-chloro-l-methyl-4- nitro-lH-pyrazole (900 mg, 5.57 mmol) and cyclopropanol (970.713 mg, 16.713 mmol) in MeCN (7.27 mL) at rt. Addition was done portionwise. The mixture was stirred at rt for 3hours. Water was added and the mixture acidified with 3N HCl(aq). The reaction mixture was extracted with DCM, dried over MgS04, filtered and evaporated. A purification was performed via preparative LC (Stationary phase: irregular SiOH 15- 40muiotaeta 80g GraceResolv, Mobile phase: gradient from 100% DCM to 98% DCM, 2% MeOH, 0, 1% NH4OH) to afford intermediate 620 (470 mg, yield 46 %).
The synthetic route of 5-Chloro-1-methyl-4-nitro-1H-pyrazole has been constantly updated, and we look forward to future research findings.
Reference:
Patent; JANSSEN PHARMACEUTICA NV; STANSFIELD, Ian; QUEROLLE, Olivier, Alexis, Georges; LIGNY, Yannick, Aime, Eddy; GROSS, Gerhard, Max; JACOBY, Edgar; MEERPOEL, Lieven; GREEN, Simon, Richard; HYND, George; KULAGOWSKI, Janusz, Jozef; MACLEOD, Calum; MANN, Samuel, Edward; (472 pag.)WO2018/2217; (2018); A1;,
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