Synthetic Route of 70951-85-8,Some common heterocyclic compound, 70951-85-8, name is 4-Bromo-1-(tert-butyl)-1H-pyrazole, molecular formula is C7H11BrN2, 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 stirred mixture of 4-bromo-1-tert-butyl-pyrazole 3.1 (50 g) in 230 mL THF was added dropwise 2.5M N-butyllithium (100 mL, hexane) under argon atmosphere below -60 00, then the mixture was stirred at this temperature for 5 mm, before 2-lsopropoxy-4,4,5,5- tetramethyl-1 ,3,2-dioxaborolane (52 mL) were added dropwise below -60 00 The reaction mixture was allowed to reach ambient temperature. The mixture was cooled with an ice bath and diluted with aqueous phosphate buffer and water and neutralized with 2M aqueous hydrochloric acid. The organic solvent was removed by destillation and the residue was extracted with DCM. The combined organic extracts were washed with saturated brine, dried over sodium sulfate, filtered and concentrated in vacuo to yield 1-tert-butyl-4-(4,4,5,5- tetramethyl-1 ,3,2-dioxaborolan-2-yl)pyrazole (44.26 g) as solid.Analysis: HPLC-MS: R1 = 0.904 mm (method F), M+H = 251
The synthetic route of 70951-85-8 has been constantly updated, and we look forward to future research findings.