Reacción #92314

Ecuación de reacción

1,3-dibromo-5,5-dimethylhydantoin

(S)-3-cyclohexene-1-carboxylic acid (R)-α-phenylethylamine salt

ethyl acetate

sodium thiosulfate

→

title compound

Rendimiento 84.0%

(1S,4S,5S)-4-Bromo-6-oxabicyclo[3.2.1]octan-7-one

Rendimiento 84.0%

Disolventes

acetonitrile

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturahad been cooled on ice
2. 2
   Otroto separate it
3. 3
   ExtracciónThe aqueous layer was extracted with ethyl acetate (50 ml)
4. 4
   Lavadowere then washed with a 5% citric acid aqueous solution (40 ml)
5. 5
   LavadoThe resulting organic layer was washed with saturated saline (30 ml)
6. 6
   Concentraciónwas then concentrated under reduced pressure
7. 7
   workup.ADDITIONThereafter, isopropyl alcohol (50 ml) was added to the residue
8. 8
   Concentraciónthe solvent was then concentrated under reduced pressure, so that the volume
9. 9
   TemperaturaThe obtained slurry liquid was cooled to −10° C.
10. 10
    Filtracióna precipitate was filtered
11. 11
    Lavadowas then washed with ice-
12. 12
    Temperaturacooled isopropyl alcohol (10 ml)

Procedimiento

Under a nitrogen atmosphere, 1,3-dibromo-5,5-dimethylhydantoin (4) (11.6 g, 40.6 mol) was added to a solution of (S)-3-cyclohexene-1-carboxylic acid (R)-α-phenylethylamine salt (2-b) (10.0 g, 40.4 mmol) in acetonitrile (25 ml) that had been cooled on ice. The temperature of the reaction solution was increased to room temperature, and the reaction solution was then stirred for 2 hours. Thereafter, ethyl acetate (50 ml) and a 10% sodium thiosulfate aqueous solution (40 ml) were added to the reaction solution to separate it. The aqueous layer was extracted with ethyl acetate (50 ml), and the organic layers were gathered and were then washed with a 5% citric acid aqueous solution (40 ml). The resulting organic layer was washed with saturated saline (30 ml) and was then concentrated under reduced pressure. Thereafter, isopropyl alcohol (50 ml) was added to the residue, and the solvent was then concentrated under reduced pressure, so that the volume became 30 ml. The obtained slurry liquid was cooled to −10° C., and a precipitate was filtered and was then washed with ice-cooled isopropyl alcohol (10 ml) to obtain the title compound (6.9 g, yield: 84%).

Fuente