Reaktion #929531

Reaktionsgleichung

zeaxanthin

sodium metabisulfite

water

sodium bromate

→

astaxanthin

Lösungsmittel

chloroform

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONTo this mixture was added dropwise over three hours at temperatures between 20 to 30° C.
2. 2
   workup.ADDITIONAfter addition
3. 3
   Filtrationthe reaction mixture was filtered through Celite
4. 4
   Sonstigethe aqueous phase was separated
5. 5
   SonstigeThe chloroform was removed by vacuum evaporation at 40-42° C
6. 6
   workup.ADDITIONThe resulting slightly wet solid was added to 190 ml
7. 7
   Temperaturcooled slowly to −10° C
8. 8
   FiltrationThe resulting solid was filtered off
9. 9
   Sonstigedried under vacuum

Vorschrift

To a suitable flask was added 20 grams of a natural product mixture containing 12.2 grams zeaxanthin (21.4 mmoles) slurried in 200 ml of chloroform. To this mixture was added a solution of 8.05 gms (53.3 mmoles) of sodium bromate. To this mixture was added dropwise over three hours at temperatures between 20 to 30° C., 8 ml of a solution prepared by dissolving 6.66 gms of sodium metabisulfite in 24 ml of water. After addition, the reaction mixture was filtered through Celite and the aqueous phase was separated. The chloroform was removed by vacuum evaporation at 40-42° C. The resulting slightly wet solid was added to 190 ml of warm (50° C.) 95% ethanol. The mixture was stirred and cooled slowly to −10° C. The resulting solid was filtered off and dried under vacuum to produce 8.8 grams (72.14%) yield of astaxanthin product containing greater than 25% astaxanthin.

Quelle