Application of 13808-64-5, These common heterocyclic compound, 13808-64-5, name is 4-Bromo-3-methylpyrazole, 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.
A solution of 4-bromo-3-methyl-1H-pyrazole 1a (500 mg, 3.13 mmol), Cs2CO3 (2.04 g, 6.25 mmol) and 1-chloropropan-2-one (862 mg, 9.38 mmol) in DMF (3 mL) was stirred at 90 C under MW for 1.5 h. The reaction mixturewas cooled to room temperature and water (15 mL) was added. It was extracted with DCM (30 mL*3), and the organiclayers were combined and washed with water (15 mL*2) and brine (15 mL * 2), dried over Na2SO4, filtrated and evaporated.The residue was purified by column to give 1-(4-bromo-3-methyl-1H-pyrazol-1-yl)propan-2-one 1b (700 mg, crude) asa yellow oil.1H NMR (400 MHz, CDCl3) delta 7.50 (d, 1H), 4.86 (d, 2H), 2.31-2.15 (m, 6H)
Statistics shows that 4-Bromo-3-methylpyrazole is playing an increasingly important role. we look forward to future research findings about 13808-64-5.