N-bromobutanimide → 2-Bromo-3-methoxycyclopent-2-enone

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

N-Bromosuccinimide (24.92 g, 0.140 mol) is added, portionwise, over 1 hour to a stirred solution of 3-methoxycyclopent-2-enone (14.95 g, 0.133 mol) in 1,2-dichloroethane (300 ml) at 0° C. in an amber flask. The reaction mixture is stirred at 0° C. for a further 90 minutes and then any remaining solid is removed by filtration. The filtrate is evaporated to dryness under reduced pressure, the resultant solid is dissolved in warm toluene (600 ml) and washed quickly with ice-cold water (2×100 ml). The organic phase is dried over anhydrous magnesium sulfate, filtered and the filtrate evaporated under reduced pressure until approximately 150 ml remains. The residue is cooled with an ice bath and left for 30 minutes. The resultant solid is removed by filtration, washed with hexane (50 ml) and air-dried to give 2-bromo-3-methoxycyclopent-2-enone.

Herkunft & Nachweise