Reference of 71229-85-1, These common heterocyclic compound, 71229-85-1, name is 4-Bromo-1-ethyl-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.
[0511j A solution of (6-bromo- i-ethyl-S -fluoro- 1 H-benzo [d]imidazol-2- yl)diphenylmethanol (0.21 g, 0.50 mmol), 4,4,4?,4?,S ,S ,S?,S?-octamethyl-2,2?-bi( 1,3,2- dioxaborolane) (0.25 g, 1.0 mmol), i,i?-bis(diphenylphosphino)ferrocenepalladium(II) dichloride (0.035 g, 0.050 mmol) and potassium acetate (0.098 g, 1.0 mmol) in dioxane (10 mL) was stirred at reflux for 5 hours. After cooling to ambient temperature, 4-bromo-i-ethyl- 1H-pyrazole (0.088 g, 0.5 mmol), tetrakis(triphenylphosphine)palladium (0) (0.055 g, 0.05 mmol), cesium carbonate (0.33 g, 1.0 mmol) and water (3 mL) were added. The reaction mixture was stirred at 100 C for 12 hours. After cooling to ambient temperature, ethyl acetate and water were added. The organic layer was separated, washed with brine, dried (sodium sulfate), filtered and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel to give (i-ethyl-6-(i-ethyl-1H-pyrazol-4-yl)-5-fluoro- 1H-benzo[d]imidazol-2-yl)diphenylmethanol (0.10 g, 45%) as solid. LCMS ESI (+) mlz 441 (M+H).
The synthetic route of 71229-85-1 has been constantly updated, and we look forward to future research findings.