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

Temperatur

0 °C

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.

1. customany remaining solid is removed by filtration
2. customThe filtrate is evaporated to dryness under reduced pressure
3. dissolutionthe resultant solid is dissolved in warm toluene (600 ml)
4. washwashed quickly with ice-cold water (2×100 ml)
5. dry with materialThe organic phase is dried over anhydrous magnesium sulfate
6. filtrationfiltered
7. customthe filtrate evaporated under reduced pressure until approximately 150 ml
8. temperatureThe residue is cooled with an ice bath
9. waitleft for 30 minutes
10. customThe resultant solid is removed by filtration
11. washwashed with hexane (50 ml)
12. customair-dried

ORD-Eintrag

ord-40358d0d904d4f59826a9b3259dccb2d

Quelldatensatz

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08754242B2