tert-Butyl methyl ether → 2-Cyclopenten-1-ol, 4-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-, cis-

HRID 2542

Reaction equation

HRID 2542 reaction equation
[O:1]([CH:9]1[CH2:13][C:12](=[O:14])[CH:11]=[CH:10]1)[Si:2]([C:5]([CH3:8])([CH3:7])[CH3:6])([CH3:4])[CH3:3].[Br-].[Li+].[H-].[Al+3].[Li+].[H-].[H-].[H-].COC(C)(C)C>C1(C)C=CC=CC=1>[Si:2]([O:1][C@@H:9]1[CH2:13][C@H:12]([OH:14])[CH:11]=[CH:10]1)([C:5]([CH3:8])([CH3:7])[CH3:6])([CH3:4])[CH3:3]

Participants

6

Reactant 4

HCID 15413tert-Butyl methyl etherHCID 82050Lithium BromideHCID 41316994-((tert-Butyl(dimethyl)silyl)oxy)cyclopent-2-en-1-oneHCID 21226445Aluminium lithium hydride

Product 1

HCID 101767472-Cyclopenten-1-ol, 4-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-, cis-Yield 69.2%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
-20 °C

Procedure

A mechanically stirred solution of 4-tert-butyldimethylsiloxy-2-cyclopentenone (501 mg, 2.36 mmol) in anhydrous toluene (10 mL) under an atmosphere of argon is treated with lithium bromide (1.06 g, 12.2 mmol). The mixture is cooled to -20° C. with an ice/salt bath and treated with lithium aluminum hydride (92.0 mg, 2.42 mmol) in one portion followed by tert-butyl methyl ether (1.0 mL). The ice/salt bath is replaced with an ice bath and the reaction is then stirred for 2 hours at 0° C. It is then quenched by slow addition of aqueous sodium hydroxide (1N, 7.0 mL) at a rate that maintains the temperature of the reaction below 20° C. The resulting suspension is then filtered through a pad of diatomaceous earth and the pad is subsequently rinsed with toluene. The filtrate phases are separated and the aqueous phase is extracted with toluene. The organic phase and organic extract are combined, rinsed with aqueous sodium hydroxide (1N), brine, dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum (40° C., 20 mmHg). The residue is then purified by Kugelrohr distillation (60°-80° C., 1 mmHg) to provide the title compound (350 mg, 69% yield) as a colorless oil; cis/trans/1-2+1-4 addition, 92.7/6.3/1.0.

Workup

  1. customIt is then quenched by slow addition of aqueous sodium hydroxide (1N, 7.0 mL) at a rate
  2. customthe temperature of the reaction below 20° C
  3. filtrationThe resulting suspension is then filtered through a pad of diatomaceous earth
  4. washthe pad is subsequently rinsed with toluene
  5. customThe filtrate phases are separated
  6. extractionthe aqueous phase is extracted with toluene
  7. extractionThe organic phase and organic extract
  8. washrinsed with aqueous sodium hydroxide (1N), brine
  9. dry with materialdried over anhydrous magnesium sulfate
  10. filtrationfiltered
  11. concentrationconcentrated under vacuum (40° C., 20 mmHg)
  12. distillationThe residue is then purified by Kugelrohr distillation (60°-80° C., 1 mmHg)

Sources & evidence

ORD record
ord-72213fef623a4ce0b58fb21b87067c20
Source dataset
uspto-grants-1998_03
Patent number
US05728899

Linked notes

Loading…