Acetate → Cholesta-5,7-dien-3beta-yl acetate

HRID 358003Notes

Reaction equation

HRID 358003 reaction equation
C([O-])(=O)C.[C:5]([O:8][C@H:9]1[CH2:33][CH2:32][C@@:31]2([CH3:34])[C:11](=[CH:12][C@@H:13](Br)[C@@H:14]3[C@@H:30]2[CH2:29][CH2:28][C@@:27]2([CH3:35])[C@H:15]3[CH2:16][CH2:17][C@@H:18]2[C@H:19]([CH3:26])[CH2:20][CH2:21][CH2:22][CH:23]([CH3:25])[CH3:24])[CH2:10]1)(=[O:7])[CH3:6].[F-].C([N+](CCCC)(CCCC)CCCC)CCC.O>O1CCCC1>[CH3:26][C@@H:19]([C@@H:18]1[C@@:27]2([CH3:35])[CH2:28][CH2:29][C@@H:30]3[C@@:31]4([CH3:34])[CH2:32][CH2:33][C@H:9]([O:8][C:5]([CH3:6])=[O:7])[CH2:10][C:11]4=[CH:12][CH:13]=[C:14]3[C@@H:15]2[CH2:16][CH2:17]1)[CH2:20][CH2:21][CH2:22][CH:23]([CH3:24])[CH3:25]

Participants

6

Reactant 4

HCID 175AcetateHCID 962Water2×HCID 2724141Tetrabutylammonium Fluoride2×HCID 16092330HCID 16092330, compound

Product 1

HCID 99487Cholesta-5,7-dien-3beta-yl acetate

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

507.6 mg of the pure 7α-bromocholester acetate obtained sub (a) were dissolved in 5 ml of anhydrous tetrahydrofuran. To this solution was added at 25° C. a solution of 1.0 g of tetrabutyl ammonium fluoride which contained per mol 1 mol of crystal water, in 5 ml of anhydrous tetrahydrofuran, and then, after stirring at 20°-25° C. for 60 minutes, 10 ml of petroleum ether (40°-60° C.). The 1 mole crystal water-containing tetrabutyl ammonium fluoride was obtained by freeze-drying a 10% solution in water. After washing the reaction mixture three times with 10 ml of water, the organic layer was evaporated to dryness. 426 mg (100%) of dry substance were obtained with a content of 7-dehydrocholesterol acetate of 100% (UV). The final product could be recrystallized from ethanol in which 400 mg of white crystalline material were obtained with a melting-point of 128°-129° C. The crystalline final product was 100% pure Δ5,7-cholestadienol acetate both according to the UV-absorption spectrum and according to the NMR spectrum.

Workup

  1. customwas obtained
  2. dry with materialby freeze-drying a 10% solution in water
  3. washAfter washing the reaction mixture three times with 10 ml of water
  4. customthe organic layer was evaporated to dryness

Sources & evidence

ORD record
ord-76b4c06f7dcb48a690ec07461338f97a
Source dataset
uspto-grants-1984_08
Patent number
US04464298

Reaction notes

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