Some common heterocyclic compound, 26621-44-3, name is 3-Nitro-1H-pyrazole, molecular formula is C3H3N3O2, 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. Computed Properties of C3H3N3O2
Production Example 405 4-Bromo-3-nitro-1-trityl-1H-pyrazole 1.42 ML bromine was added at room temperature to a mixture of 3.13 g 3-nitro-1H-pyrazole (compound described in Janssen et al., J. Org. Chem., 36, 3081 (1971)) and 60 ML acetic acid, and the mixture was stirred for 6 hours.. Iced water was added to the reaction solution which was then neutralized with 5 N aqueous sodium hydroxide and an aqueous saturated ammonium chloride solution.. By adding ethyl acetate and water, the aqueous layer was separated.. The aqueous layer was saturated with common salt and extracted with ethyl acetate.. The combined organic layer was washed with an aqueous brine and then dried over anhydrous sodium sulfate.. The drying agent was filtered off, and the filtrate was evaporated. 5.41 g crude product of 4-bromo-3-nitro-1H-pyrazole was obtained as pale brown crystals.. From this compound, 11.05 g of the title compound was obtained as pale brown crystals by the same method as in Production Example 15.1H-NMR (CDCl3) delta: 7.10(m, 6H), 7.27-7.40(m, 9H), 7.46(s, 1H)
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 26621-44-3, its application will become more common.
Reference:
Patent; Eisai Co., Ltd.; EP1382603; (2004); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics