Réaction #2467933

ord-d1ff980968f943d1a2170927d015c4c1

Équation de réaction

O=Cc1cc(Br)cc(Br)c1
3,5-dibromobenzaldehyde
CC(C)(C)[O-].[K+]
potassium t-butoxide
[Cl-].[NH4+]
ammonium chloride
C=Cc1cc(Br)cc(Br)c1
3,5-dibromostyrene
Rendement 79.3%

Conditions de réaction

Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    Températurecooling
  2. 2
    TempératureThe resultant slurry was cooled to −78° C.
  3. 3
    workup.ADDITIONwas added dropwise
  4. 4
    Températureto warm to room temperature
  5. 5
    workup.STIRRINGstirred for 1 hr
  6. 6
    ExtractionThe product was extracted with ethyl acetate
  7. 7
    workup.DISTILLATIONthe solvent was distilled off under reduced pressure
  8. 8
    Autrethe residue was purified with silica-gel column chromatography

Mode opératoire

Tetrahydrofuran (20 mL) was added to methyltriphenylphosphonium bromide (3.150 g, 8.8 mmol). Then potassium t-butoxide (0.989 g, 8.8 mmol) was added herein small portions with ice-cooling, and the mixture was stirred at room temperature for 1 hr. The resultant slurry was cooled to −78° C. and a tetrahydrofuran (20 mL) solution containing 3,5-dibromobenzaldehyde (1.519 g, 5.8 mmol) was added dropwise. The reaction solution was allowed to warm to room temperature and stirred for 1 hr, and then a saturated ammonium chloride aqueous solution was added to the reaction solution. The product was extracted with ethyl acetate, the solvent was distilled off under reduced pressure, and the residue was purified with silica-gel column chromatography to obtain 3,5-dibromostyrene (1.2 g, 4.6 mmol).

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US08257837B2uspto-grants-2012_09