Citric Acid → HCID 118565915, Verbindung

Temperatur

5 °C

(1S,4S,5S)-4-Bromo-6-oxabicyclo[3.2.1]octan-7-one (200 g) was added to ethyl acetate (1000 ml), and the obtained solution was then cooled to 5° C. Thereafter, a 50% dimethylamine aqueous solution (305.7 ml) was added to the reaction solution, and the obtained mixture was then stirred for 14 hours. Thereafter, a mixed solution of citric acid (131.17 g), common salt (92.00 g) and water (324 ml) was added to the reaction solution, and the obtained mixture was then heated to 30° C. The reaction solution was stirred for 30 minutes, and thereafter, it was left at rest, so that the organic layer was separated. Further, the aqueous layer was extracted with ethyl acetate (800 ml) again. The organic layers were gathered, and the gathered organic layer was then concentrated to 1000 ml. Water (400 ml) was added to the concentrated solution, and the thus mixed solution was concentrated again to obtain an aqueous solution (500 ml) of (1S,3S,4S)-3-hydroxy-4-bromo-N,N-dimethylcyclohexanecarboxamide. To this aqueous solution (500 ml), a 28% ammonia aqueous solution (1247 ml) and a 25% sodium hydroxide aqueous solution (123 ml) were added, and the obtained solution was then heated to 40° C., followed by stirring the reaction solution for 6 hours. Thereafter, the reaction solution was concentrated to 1000 ml to obtain an aqueous solution containing the title compound (147.52 g, yield: 81%).

1. temperaturethe obtained mixture was then heated to 30° C
2. stirringThe reaction solution was stirred for 30 minutes
3. waitit was left at rest, so that the organic layer
4. customwas separated
5. extractionFurther, the aqueous layer was extracted with ethyl acetate (800 ml) again
6. concentrationthe gathered organic layer was then concentrated to 1000 ml
7. additionWater (400 ml) was added to the concentrated solution
8. concentrationthe thus mixed solution was concentrated again

ORD-Eintrag

ord-c241c586c69a455ba9dd3de37d452b81

Quelldatensatz

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09447118B2