Sodium borohydride → 1alpha,3beta-bis(tert-butyldimethylsilyloxy)-20(R)-hydroxypregna-5,7,16-triene

HRID 635029Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 635029
[C:1]([Si:5]([CH3:38])([CH3:37])[O:6][C@@H:7]1[C@@:26]2([CH3:27])[C:11](=[CH:12][CH:13]=[C:14]3[C@@H:25]2[CH2:24][CH2:23][C@@:22]2([CH3:28])[C@H:15]3[CH2:16][CH:17]=[C:18]2[C:19](=[O:21])[CH3:20])[CH2:10][C@@H:9]([O:29][Si:30]([C:33]([CH3:36])([CH3:35])[CH3:34])([CH3:32])[CH3:31])[CH2:8]1)([CH3:4])([CH3:3])[CH3:2].O.O.O.O.O.O.O.[Cl-].[Ce+3].[Cl-].[Cl-].[BH4-].[Na+]>CO.O1CCCC1>[Si:5]([O:6][C@@H:7]1[C@@:26]2([CH3:27])[C:11](=[CH:12][CH:13]=[C:14]3[C@@H:25]2[CH2:24][CH2:23][C@@:22]2([CH3:28])[C@H:15]3[CH2:16][CH:17]=[C:18]2[C@H:19]([OH:21])[CH3:20])[CH2:10][C@@H:9]([O:29][Si:30]([C:33]([CH3:34])([CH3:36])[CH3:35])([CH3:31])[CH3:32])[CH2:8]1)([C:1]([CH3:4])([CH3:3])[CH3:2])([CH3:38])[CH3:37].[Si:5]([O:6][C@@H:7]1[C@@:26]2([CH3:27])[C:11](=[CH:12][CH:13]=[C:14]3[C@@H:25]2[CH2:24][CH2:23][C@@:22]2([CH3:28])[C@H:15]3[CH2:16][CH:17]=[C:18]2[C@@H:19]([OH:21])[CH3:20])[CH2:10][C@@H:9]([O:29][Si:30]([C:33]([CH3:34])([CH3:36])[CH3:35])([CH3:31])[CH3:32])[CH2:8]1)([C:1]([CH3:4])([CH3:3])[CH3:2])([CH3:38])[CH3:37]

Komponenten

7

Edukt 3

HCID 4311764Sodium borohydrideHCID 120200821alpha,3beta-Bis(tert-butyldimethylsilyloxy)-20-oxopregna-5,7,16-trieneHCID 21585214Cerium trichloride heptahydrate

Produkt 2

HCID 120200781alpha,3beta-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-trieneAusbeute 18 %HCID 120200831alpha,3beta-bis(tert-butyldimethylsilyloxy)-20(R)-hydroxypregna-5,7,16-trieneAusbeute 73 %

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 887MethanolLösungsmittelHCID 8028TetrahydrofuranLösungsmittel

Versuchsvorschrift

To a solution of 1α,3β-bis(tert-butyldimethyl-silyloxy)-20-oxopregna-5,7,16-triene (93 mg, 0.167 mmol) and cerium (III) chloride heptahydrate (93 mg, 0.251 mmol) in methanol (1.5 ml) and tetrahydrofuran (6 ml) cooled at 0° C. was gradually added sodium borohydride (32 mg, 0.835 mmol). The reaction solution was stirred at room temperature for one hour, then concentrated under reduced pressure and the residue was taken into water and extracted with ethyl acetate. The organic layer was washed with brine and then dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The resulting residue was purified by preparative thin layer chromatography (0.5 mm×2, hexane:ethyl acetate=10:1, developed three times) to give the title compound as a colorless solid (68.2 mg, 73%) and 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-triene (17.0 mg, 18%).

Aufarbeitung

  1. concentrationconcentrated under reduced pressure
  2. extractionextracted with ethyl acetate
  3. washThe organic layer was washed with brine
  4. dry with materialdried over magnesium sulfate
  5. distillationthe solvent was distilled off under reduced pressure
  6. customThe resulting residue was purified by preparative thin layer chromatography (0.5 mm×2, hexane:ethyl acetate=10:1, developed three times)

Quellen und Nachweise

ORD-Eintrag
ord-c8760235815346079ad1ca264d325066
Quelldatensatz
uspto-grants-2001_02
Patentnummer
US06184398B2

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