Reference of 2075-45-8,Some common heterocyclic compound, 2075-45-8, name is 4-Bromo-1H-pyrazole, molecular formula is C3H3BrN2, 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.
To a solution of 4-bromo-lH-pyrazole (21.6 g, 147 mmol) in dichloromethane (400 mL) from Step 1 was added HCl (4 N in dioxane) (2.204 mL, 8.82 mmol )And ethoxyethylene (12.72 g, 176 mmol). After stirring the mixture for 30 min at rt, the reaction was quenched with aqueous NaHCO3 (30 mL), stirred at rt for 1 h, and the two layers were separated. The organic layer was washed with water, dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford 28 g of crude product. The material was purified by flash chromatography using silica gel using a hexane / ethyl acetate mixture as a solvate. A portion of the main product containing the uv activity was combined and concentrated in vacuo to afford 13.2 g (41%) of the desired product as a clear oil
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 4-Bromo-1H-pyrazole, its application will become more common.