Hydrochloric Acid → (3aR,4S,5R,6aS)-4-[[tert-butyl(dimethyl)silyl]oxymethyl]-5-hydroxy-3,3a,4,5,6,6a-hexahydrocyclopenta[b]furan-2-one

HRID 371446Notes

Reaction equation

HRID 371446 reaction equation
C(=O)([O-])[O-].[K+].[K+].[Si:7]([O:14][CH2:15][C@H:16]1[C@H:23]([O:24]C(=O)C2C=CC=CC=2)[CH2:22][C@H:21]2[C@@H:17]1[CH2:18][C:19](=[O:33])[O:20]2)([C:10]([CH3:13])([CH3:12])[CH3:11])([CH3:9])[CH3:8].Cl>CO>[Si:7]([O:14][CH2:15][C@H:16]1[C@H:23]([OH:24])[CH2:22][C@H:21]2[C@@H:17]1[CH2:18][C:19](=[O:33])[O:20]2)([C:10]([CH3:13])([CH3:12])[CH3:11])([CH3:9])[CH3:8]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 11430Potassium CarbonateHCID 2724503(3aR,4S,5R,6aS)-4-(((tert-Butyldimethylsilyl)oxy)methyl)-2-oxohexahydro-2H-cyclopenta[b]furan-5-yl benzoate

Product 1

HCID 10613232(3aR,4S,5R,6aS)-4-[[tert-butyl(dimethyl)silyl]oxymethyl]-5-hydroxy-3,3a,4,5,6,6a-hexahydrocyclopenta[b]furan-2-oneYield 76.4%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

1.845 g of anhydrous potassium carbonate is introduced into a solution of 11.716 g of the silyl ether produced in Example 1 in 122 ml of absolute MeOH, and the mixture is agitated under argon for 3 hours. The reaction solution is then cooled in an ice bath and gently combined dropwise with 1.86 ml of concentrated hydrochloric acid. Excess methanol is extensively concentrated under vacuum at room temperature, the residue is combined with 300 ml of methylene chloride, and the solution is dried over magnesium sulfate, filtered off, and concentrated. The oily residue is made to crystallize by trituration with hexane, thus obtaining 6.562 g of the title compound, mp 60.7° C.

Workup

  1. temperatureThe reaction solution is then cooled in an ice bath
  2. concentrationExcess methanol is extensively concentrated under vacuum at room temperature
  3. dry with materialthe solution is dried over magnesium sulfate
  4. filtrationfiltered off
  5. concentrationconcentrated
  6. customto crystallize by trituration with hexane

Sources & evidence

ORD record
ord-7f63074b83494eb291fe191d514c5e0a
Source dataset
uspto-grants-1985_07
Patent number
US04532236

Reaction notes

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