Dibenzo-18-crown-6 → 1alpha,3beta-Bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-triene

HRID 1792196Notes

Reaction equation

HRID 1792196 reaction equation
[Si:1]([O:8][C@@H:9]1[C@@:29]2([CH3:30])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:31])[C@H:17]3[CH2:18][CH:19]=[C:20]2[C:21]([OH:24])([CH3:23])[CH3:22])[CH2:12][C@@H:11]([O:32][Si:33]([C:36]([CH3:39])([CH3:38])[CH3:37])([CH3:35])[CH3:34])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[H-].[K+].C1OCCOC2C(=CC=CC=2)OCCOCCOC2C(=CC=CC=2)OC1.[O:68]1[C:70]([CH2:73][CH3:74])([CH2:71][CH3:72])[CH2:69]1>C1(C)C=CC=CC=1>[Si:1]([O:8][C@@H:9]1[C@@:29]2([CH3:30])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:31])[C@H:17]3[CH2:18][CH:19]=[C:20]2[C:21]([O:24][CH2:69][C:70]([CH2:73][CH3:74])([OH:68])[CH2:71][CH3:72])([CH3:23])[CH3:22])[CH2:12][C@@H:11]([O:32][Si:33]([C:36]([CH3:39])([CH3:38])[CH3:37])([CH3:34])[CH3:35])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[Si:1]([O:8][C@@H:9]1[C@@:29]2([CH3:30])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:31])[C@H:17]3[CH2:18][CH:19]=[C:20]2[C:21]([OH:24])([CH3:23])[CH3:22])[CH2:12][C@@H:11]([O:32][Si:33]([C:36]([CH3:39])([CH3:38])[CH3:37])([CH3:34])[CH3:35])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]

Participants

7

Reactant 4

HCID 26541Dibenzo-18-crown-6HCID 82127Potassium hydrideHCID 2959712,2-DiethyloxiraneHCID 696299251alpha,3beta-Bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-triene

Product 2

HCID 696299251alpha,3beta-Bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-trieneYield 53%HCID 696301181alpha,3beta-Bis(tert-butyldimethylsilyloxy)-20-(2-ethyl-2-hydroxybutoxy)-20-methylpregna-5,7,16-trieneYield 10%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

1α,3β-Bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-triene (261.4 mg, 0.456 mmol), potassium hydride (35% in oil, 0.53 ml, 4.625 mmol), dibenzo-18-crown-6 (165 mg, 0.458 mmol), toluene (0.75 ml) and 1,2-epoxy-2-ethylbutane (450 mg, 4.493 mmol) were subjected to reaction using a procedure similar to that of Example 21(1) (at external temperature of 95° C. for 2 hours and 10 min.), worked up and the thus obtained residue was purified by column chromatography (hexane:ethyl acetate=10:1) and preparative thin layer chromatography (1 sheet (0.5 mm thickness), hexane:ethyl acetate=20:1, developed twice) to give the titled compound (32.0 mg, 10%) and 1α,3β-bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-triene (138.5 mg, 53%), each as a colorless oil.

Workup

  1. customof Example 21(1) (at external temperature of 95° C. for 2 hours and 10 min.)
  2. customthe thus obtained residue was purified by column chromatography (hexane:ethyl acetate=10:1) and preparative thin layer chromatography (1 sheet (0.5 mm thickness), hexane

Sources & evidence

ORD record
ord-a48de7423d424028b2566e49051c6707
Source dataset
uspto-grants-2006_07
Patent number
US07074777B2

Reaction notes

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