N-bromobutanimide → 2-Bromo-1-(5-bromopyrazin-2-yl)ethan-1-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-bromo-5-(1-ethoxyvinyl)pyrazine (0.65 g, 2.84 mmol) in THF and water was added NBS (0.505 g, 2.84 mmol) at 0° C. The reaction mixture was stirred at 0° C. for 1 hr, then diluted with EtOAc and aq. KF. The two phase mixture was stirred for 20 min at rt before being filtered through diatomaceous earth (Celite®). The filtrate was washed with sat. NaHCO3, sat. NaCl, dried over anhydrous Na2SO4, concentrated. The crude product was purified by silica gel chromatography (0-100% EtOAc in hexane) to yield 2-bromo-1-(5-bromopyrazin-2-yl)ethanone (0.38 g) as a yellow oil. LC/MS (Cond. N-1): [M+H]+ 280.91, RT=2.945 min.

Provenance & Evidence