4-Bromopyrazole → 4-bromo-1-[(3-methyloxetan-3-yl)methyl]-1H-pyrazole

Participants

Reaction Steps

To a suspension of NaH (98 mg, 55% in mineral oil, 2.25 mmol) in DMF (1.2 ml) was added a solution of 4-bromopyrazole (300 mg, 2.04 mmol) in DMF (2 ml). The reaction mixture was stirred at room temperature for 15 minutes before a solution of 3-bromomethyl-3-methyloxetane (404 mg, 2.45 mmol) in DMF (2 ml) was added slowly. The mixture was stirred at room temperature for 1.5 h, then diluted with saturated NaHCO3 solution and extracted with 3 times with EtOAc. The combined organic layers were washed 2 times with water and with brine, dried (Na2SO4) and evaporated. The remaining colorless oil was purified by silica gel chromatography (heptane/EtOAc 80:20-50:50) to obtain the title compound (444 mg, 94%) as colorless oil. MS (EI): 231.2 (M+H)+.

Provenance & Evidence