Water → Cholesta-5,7-diene-1,3-diol

HRID 1587617Notes

Reaction equation

HRID 1587617 reaction equation
[CH3:1][CH:2]([C@@H:13]1[C@:30]2([CH3:31])[C@H:16]([C:17]3[C@H:27]([CH2:28][CH2:29]2)[C@:25]2([CH3:26])[C:20]([CH2:21][C@@H:22]([O:37]C(OC)=O)[CH2:23][C@@H:24]2[O:32]C(OC)=O)=[CH:19][CH:18]=3)[CH2:15][CH2:14]1)[CH2:3]S(C1C=CC=CC=1)(=O)=O.C[Si](C)(C)[N-][Si](C)(C)C.[Li+].[CH2:52](Br)[CH2:53][CH:54]([CH3:56])[CH3:55].O>O1CCCC1>[CH3:55][CH:54]([CH2:53][CH2:52][CH2:3][C@H:2]([C@@H:13]1[C@:30]2([CH3:31])[C@H:16]([C:17]3[C@H:27]([CH2:28][CH2:29]2)[C@:25]2([CH3:26])[C:20]([CH2:21][C@@H:22]([OH:37])[CH2:23][C@@H:24]2[OH:32])=[CH:19][CH:18]=3)[CH2:15][CH2:14]1)[CH3:1])[CH3:56]

Participants

6

Reactant 4

HCID 962WaterHCID 78911-Bromo-3-methylbutaneHCID 2733832Lithium HexamethyldisilazideHCID 541055811alpha,3beta-Bis(methoxycarbonyloxy)-20-methyl-21-phenylsulfonylpregna-5,7-diene

Product 1

HCID 193829Cholesta-5,7-diene-1,3-diolYield 62.8%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-70 °C

Procedure

In 1 ml of tetrahydrofuran was dissolved 35 mg of 20-methyl-1α,3β-bis(methoxycarbonyloxy)-21-phenylsulfonylpregna-5,7-diene and the solution was cooled to -70° C. To the solution was added 0.8 ml of 0.1N solution of lithium hexamethyldisilazide in tetrahydrofuran. The resulting mixture was stirred for 30 minutes. After addition of 30 mg of isoamyl bromide, the mixture was stirred for 4 hours while the temperature was gradually raised to room temperature. The reaction mixture was poured into water and extracted with diethyl ether. The extract was washed with an aqueous solution of sodium hydrogen carbonate and an aqueous solution of sodium chloride, then dried over sodium sulfate and concentrated. The residue was dissolved in 1 ml of methanol and treated with 500 mg of 6% sodium amalgam in the presence of 0.5 ml of disodium hydrogen phosphate at ambient temperature for 1 hour. The reaction mixture was poured into water and extracted with diethyl ether. The extract was washed with an aqueous solution of sodium chloride, dried over sodium sulfate and concentrated. The residue was dissolved in 1 ml of methanol, 10 mg of potassium carbonate was added, and the mixture was stirred for 12 hours. The reaction mixture was then subjected to the isolation and purification procedure of Reference Example 8 to give 15 mg of cholesta-5,7-diene-1α,3β-diol which showed the same 1H NMR spectrum as that obtained in Reference Example 8.

Workup

  1. stirringthe mixture was stirred for 4 hours while the temperature
  2. temperaturewas gradually raised to room temperature
  3. extractionextracted with diethyl ether
  4. washThe extract was washed with an aqueous solution of sodium hydrogen carbonate
  5. dry with materialan aqueous solution of sodium chloride, then dried over sodium sulfate
  6. concentrationconcentrated
  7. dissolutionThe residue was dissolved in 1 ml of methanol
  8. additiontreated with 500 mg of 6% sodium amalgam in the presence of 0.5 ml of disodium hydrogen phosphate at ambient temperature for 1 hour
  9. additionThe reaction mixture was poured into water
  10. extractionextracted with diethyl ether
  11. washThe extract was washed with an aqueous solution of sodium chloride
  12. dry with materialdried over sodium sulfate
  13. concentrationconcentrated
  14. dissolutionThe residue was dissolved in 1 ml of methanol
  15. addition10 mg of potassium carbonate was added
  16. stirringthe mixture was stirred for 12 hours
  17. customThe reaction mixture was then subjected to the isolation and purification procedure of Reference Example 8

Sources & evidence

ORD record
ord-1dda9d33c2d048d9828e0dc5919125c3
Source dataset
uspto-grants-1993_06
Patent number
US05218109

Reaction notes

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