Some common heterocyclic compound, 5334-39-4, name is 3-Methyl-4-nitro-1H-pyrazole, molecular formula is C4H5N3O2, 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: C4H5N3O2
A mixture of 2-(l-methyl-lH-pyrazol-3-yl)ethyl methanesulfonate (600 mg, 2.94 mmol), 3-methyl-4-nitro-lH-pyrazole (373 mg, 2.94 mmol), and Cs2C03 (1.92 g, 5.882 mmol) in DMF (20 ml) was stirred at 100 C for 2 h. H20 (20 ml) was added and the resulting mixture was extracted with EtOAc (20 ml x 3). The organic layers were combined, washed with brine (20 ml), dried over sodium sulfate, and concentrated under reduced pressure. The residue was purified by prep-TLC eluting with petroleum ether/ethyl acetate (1/1) to afford the title compound (600 mg, 87%) as a white solid. LC-MS (ESI): m/z = 236 (M+H)+.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5334-39-4, its application will become more common.
Reference:
Patent; F. HOFFMANN-LA ROCHE AG; GENENTECH, INC.; BAKER-GLENN, Charles; BURDICK, Daniel Jon; CHAMBERS, Mark; CHAN, Bryan K.; CHEN, Huifen; ESTRADA, Anthony; SWEENEY, Zachary Kevin; WO2013/164321; (2013); A1;,
Pyrazole – Wikipedia,
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