Reaktion #1993875

Reaktionsgleichung

[1α,3β,7ξ,24R]-7-bromo-24-fluorocholest-5-en-1,3,25-triol 1,3-diacetate

s-collidine

xylene

→

[1α,3β,24R]-24-fluorocholesta-5,7-dien-1,3,25-triol 1,3-diacetate

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONA mixture of 0.605 g
2. 2
   Temperaturcooled
3. 3
   workup.ADDITIONThe mixture was diluted with 30 ml
4. 4
   WaschenThis solution was washed with 10% aqueous sulfuric acid, and saturated aqueous sodium bicarbonate solution
5. 5
   TrocknenThe organic phase was dried over anhydrous magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   Sonstigeevaporated to dryness
8. 8
   SonstigeThe residue was purified by column chromatography on 0.06-0.20 mm silica gel

Vorschrift

A mixture of 0.605 g. (0.0010 mole) of [1α,3β,7ξ,24R]-7-bromo-24-fluorocholest-5-en-1,3,25-triol 1,3-diacetate, 0.6 ml. of s-collidine and 18 ml. of xylene was heated at reflux (140° C.) for 0.5 hr and cooled. The mixture was diluted with 30 ml. of toluene. This solution was washed with 10% aqueous sulfuric acid, and saturated aqueous sodium bicarbonate solution. The organic phase was dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness. The residue was purified by column chromatography on 0.06-0.20 mm silica gel to yield [1α,3β,24R]-24-fluorocholesta-5,7-dien-1,3,25-triol 1,3-diacetate, [α]D23 -21° (c 0.5, CHCl3).

Quelle