HCID 70311223, compound → HCID 21309365, compound

HRID 1075547Notes

Reaction equation

HRID 1075547 reaction equation
[C:1]([O:5][C@H:6]1[CH2:15][CH2:14][CH2:13][CH:12]2[C@:7]1([CH3:17])[CH2:8][CH2:9][CH2:10][CH:11]2[OH:16])([CH3:4])([CH3:3])[CH3:2].[Cr](Cl)([O-])(=O)=O.[NH+]1C=CC=CC=1>C(Cl)Cl.C(OCC)C>[C:1]([O:5][C@H:6]1[CH2:15][CH2:14][CH2:13][C@@H:12]2[C@:7]1([CH3:17])[CH2:8][CH2:9][CH2:10][C:11]2=[O:16])([CH3:4])([CH3:2])[CH3:3]

Participants

5

Reactant 2

HCID 70311223HCID 70311223, compoundHCID 178418287HCID 178418287, compound

Product 1

HCID 21309365HCID 21309365, compoundYield 71.1%

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 6344DichloromethaneSolvent

Procedure

To a solution of 3.4 g (14.1 mMol) of (1RS,4aS,5S,8aRS)-5-tert-Butoxy-4a-methyl-decahydro-naphtalen-1-ol in 34 ml methylenechloride was added under stirring 3.66 g (17.0 mMol) of pyridiniumchlorochromate and the reaction mixture was kept under stirring overnight. Then the reaction was diluted with 33 ml diethylether, kept stirring for 15 minutes and filtered over florisil®. The filtrate was evaporated to dryness in vacuo and the residue dissolved in 33 ml of tetrahydrofuran. Under stirring and argon atmosphere, 1.65 ml of a one molar solution of potassium-tertio-butoxide in tetrahydrofuran was added and the reaction was kept overnight. This equilibration is monitored by TLC (silica gel, hexane/ethylacetate 4/1), which shows the almost complete disappearance of one of the two epimers. The reaction mixture is evaporated in vacuo to dryness, the residue is taken up in water and extracted three times with diethylether. The combined organic phase is washed with water and brine, dried over sodium sulfate and evaporated in vacuo. The residue is chromatographed over 120 g of silica gel with hexane/ethylacetate 9/1 to yield 2.39 g (71%) of pure (4aS,5S,8aR)-5-tert-Butoxy-4a-methyl-octahydro-naphtalen-1-one. An analytical sample was obtained by crystallization from hexane with a m.p. of 78-79° C.

Workup

  1. stirringkept stirring for 15 minutes
  2. filtrationfiltered over florisil®
  3. customThe filtrate was evaporated to dryness in vacuo
  4. dissolutionthe residue dissolved in 33 ml of tetrahydrofuran
  5. stirringUnder stirring
  6. additionargon atmosphere, 1.65 ml of a one molar solution of potassium-tertio-butoxide in tetrahydrofuran was added
  7. waitthe reaction was kept overnight
  8. customThe reaction mixture is evaporated in vacuo to dryness
  9. extractionextracted three times with diethylether
  10. washThe combined organic phase is washed with water and brine
  11. dry with materialdried over sodium sulfate
  12. customevaporated in vacuo
  13. customThe residue is chromatographed over 120 g of silica gel with hexane/ethylacetate 9/1

Sources & evidence

ORD record
ord-600a22d577464ebebe6ded1e9492e453
Source dataset
uspto-grants-1999_05
Patent number
US05905074

Reaction notes

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