1,8-Diazabicyclo(5.4.0)undec-7-ene → (Z)-2,2-Dimethyl-5-(tert-butyldimethylsilyloxycarbonyl-methylene)-1,3-dioxolane

HRID 2181086Notes

Reaction equation

HRID 2181086 reaction equation
Br[C:2]1([CH2:10][C:11]([O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])=[O:12])[C:6](=O)[O:5][C:4]([CH3:9])([CH3:8])[O:3]1.N12CCCN=C1CCCCC2>C(Cl)(Cl)(Cl)Cl.O1CCCC1>[CH3:8][C:4]1([CH3:9])[O:5][CH2:6]/[C:2](=[CH:10]/[C:11]([O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:15])[CH3:16])=[O:12])/[O:3]1

Participants

5

Reactant 2

HCID 811841,8-Diazabicyclo(5.4.0)undec-7-eneHCID 235191444-Bromo-2,2-dimethyl-5-oxo-1,3-dioxolane-4-acetic acid, tert-butyldimethylsilyl ester

Product 1

HCID 69656326(Z)-2,2-Dimethyl-5-(tert-butyldimethylsilyloxycarbonyl-methylene)-1,3-dioxolane

Reagents, catalysts & solvents 2

HCID 5943Carbon TetrachlorideSolventHCID 8028TetrahydrofuranSolvent

Procedure

The solution of crude 4-bromo-2,2-dimethyl-5-oxo-1,3-dioxolane-4-acetic acid, tert-butyldimethylsilyl ester (72.4 mmol) in carbon tetrachloride (˜220 ml) was cooled to 0-5° C. and treated dropwise over 10 minutes and under good stirring with a solution of 1,8-diazabicyclo (5,4,0) undec-7-ene (12.1 g, 79.6 mmol) in dry tetrahydrofuran (125 ml). A heavy precipitate was formed which gradually became a granular solid. After 1 h, the solid obtained was filtered and washed with a small amount of tetrahydrofuran. The filtrate was concentrated under reduced pressure to give a light orange oil which was used as such for the next step.

Workup

  1. additiontreated dropwise over 10 minutes
  2. customA heavy precipitate was formed which
  3. customthe solid obtained
  4. filtrationwas filtered
  5. washwashed with a small amount of tetrahydrofuran
  6. concentrationThe filtrate was concentrated under reduced pressure
  7. customto give a light orange oil which

Sources & evidence

ORD record
ord-eba46ea695e84d93806b7fb123e49392
Source dataset
uspto-grants-2005_05
Patent number
US06890942B2

Reaction notes

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