Ammonia → Cholest-5-ene-1alpha,3beta-diol

HRID 651945Notes

Reaction equation

HRID 651945 reaction equation
[OH:1][C@@H:2]1[C@@:26]2([CH3:27])[C:6]([CH:7]=[CH:8][C@@H:9]3[C@@H:25]2[CH2:24][CH2:23][C@@:22]2([CH3:28])[C@H:10]3[CH2:11][CH2:12][C@@H:13]2[C@H:14]([CH3:21])[CH2:15][CH2:16][CH2:17][CH:18]([CH3:20])[CH3:19])=[CH:5][C:4](=[O:29])[CH2:3]1.C[Si](O[Si](C)(C)C)(C)C.C[Si](C)(C)N[Si](C)(C)C.C[Si](C)(C)Cl.[Li].N.[Cl-].[NH4+]>O1CCCC1.C(Cl)Cl.CCOCC.O.N1C=CC=CC=1>[OH:1][C@@H:2]1[C@@:26]2([CH3:27])[C:6](=[CH:7][CH2:8][C@@H:9]3[C@@H:25]2[CH2:24][CH2:23][C@@:22]2([CH3:28])[C@H:10]3[CH2:11][CH2:12][C@@H:13]2[C@H:14]([CH3:21])[CH2:15][CH2:16][CH2:17][CH:18]([CH3:20])[CH3:19])[CH2:5][C@@H:4]([OH:29])[CH2:3]1

Participants

13

Reactant 7

HCID 222AmmoniaHCID 6397ChlorotrimethylsilaneHCID 13838HexamethyldisilazaneHCID 24764Hexamethyldisiloxane2×HCID 25517Ammonium Chloride2×HCID 3028194Lithium2×HCID 139111111alpha-Hydroxycholesta-4,6-diene-3-one

Product 1

HCID 11112200Cholest-5-ene-1alpha,3beta-diol

Reagents, catalysts & solvents 5

HCID 962WaterSolventHCID 1049PyridineSolventHCID 3283Diethyl EtherSolventHCID 6344DichloromethaneSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

The hydroxy dienone from (a) (0.6 gms) was converted to its trimethylsilyl ether by treatment of a solution in tetrahydrofuran (2 mls) and pyridine (2 mls) with hexamethyldisilazane (1.5 mls) and trimethylchlorosilane (0.6 mls). The crude trimethylsilyl ether was dissolved in tetrahydrofuran (10 mls) and the solution added dropwise to a stirred solution of lithium metal (approx. 200 mgs) in liquid ammonia (20 mls). After a few minutes ammonium chloride (2 gms) was added and the solution stirred. A further portion of lithium metal (approx. 100 mgs) was added. Again the solution was stirred. An additional portion of ammonium chloride was then added and the mixture poured into cold water. The produce was isolated by extraction into ether and methylene dichloride followed by column chromatography which afforded the title compound crystallized from ethanol, melting point 158°-161°. After recrystallisation the melting point was 161.5°-163°. [α]D (CHCl3)-38 °. This material was identical to the product of Example 1(c), and on hydrogenation gave a sample of 1α,3β-dihydroxy-5α-cholestane identical in every way to an authentic specimen.

Workup

  1. stirringAgain the solution was stirred

Sources & evidence

ORD record
ord-e7202cba97fc4d95a2fd33ba5901b095
Source dataset
uspto-grants-1987_06
Patent number
US04670190

Reaction notes

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