Reaktion #2467933

Reaktionsgleichung

3,5-dibromobenzaldehyde

potassium t-butoxide

ammonium chloride

→

3,5-dibromostyrene

Ausbeute 79.3%

Lösungsmittel

Tetrahydrofuran

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

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

Vorschrift

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).

Quelle