Electric Literature of 1150271-23-0, These common heterocyclic compound, 1150271-23-0, name is tert-Butyl 4-bromo-1H-pyrazole-1-carboxylate, 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.
To a stirred degassed solution of 4-bromo-pyrazole-1 -carboxylic acid tert- butyl ester (300 mg, 1 .21 mmol) in DMF (3 mL) were added phenyl acetylene (0.24 ml_, 2.18 mmol), triethyl amine (0.84 mL, 6.05 mmol), Cul (40.16 mg, 0.24 mmol) followed by Pd(PPh3)4 (279.58 mg, 0.24 mmol). Resulting reaction mixture was heated at 70C for 6 hours. After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. Combined organic layer was dried over sodium sulfate and concentrated under reduced pressure. Crude compound was purified by column chromatography (10-20% ethyl acetate in hexane) to get tert-butyl 4-(2-phenylethynyl)-1 H-pyrazole-1-carboxylate (230 mg, 70%) as brown liquid. MS (ESI): m/z 269.3 [M+1]+.
The synthetic route of 1150271-23-0 has been constantly updated, and we look forward to future research findings.