Réaction #7292

Équation de réaction

1,4-dibromo-2,5-dimethoxy benzene

phenylacetylene

→

desired product

Rendement 75.7%

1,4-bis(phenylethynyl)-2,5-dimethoxybenzene

Rendement 75.7%

Solvants

piperidine

Conditions de réaction

Traitement

1. 1
   Autreequipped with a stirrer
2. 2
   Températurethe reaction mixture was cooled down to room temperature
3. 3
   Filtrationwas filtered off
4. 4
   AutreThe solvent was removed under a reduced pressure
5. 5
   Extractionthe residue was extracted with methylene chloride
6. 6
   LavageOrganic layer was washed with water several times
7. 7
   Séchagedried with anhydrous magnesium sulfate
8. 8
   Autrethe solvent was removed
9. 9
   Autreto obtain yellow solid
10. 10
    AutreThis solid was recrystallized from ethyl acetate
11. 11
    Autreto obtain yellow crystal, which
12. 12
    Autrewas sufficiently dried in a vacuum oven at 40° C.

Mode opératoire

50 g (160 mmol) of 1,4-dibromo-2,5-dimethoxy benzene, 3.6 g (0.005 mol) of bistriphenylphosphine palladium dichloride and 0.97 g (0.005 mol) of copper iodide were put into a 1 litter 3-neck flask equipped with a stirrer, a thermometer and a reflux condenser under an argon atmosphere, and dissolved in 500 ml of piperidine. 43 g (0.422 mol) of phenylacetylene was then slowly added dropwise at room temperature. The reaction temperature was slowly raised to 80° C. and then the reaction mixture was stirred at the same temperature for 12 hours. When the reaction was completed, the reaction mixture was cooled down to room temperature, and then generated salt was filtered off. The solvent was removed under a reduced pressure, and then the residue was extracted with methylene chloride. Organic layer was washed with water several times and dried with anhydrous magnesium sulfate, and then the solvent was removed to obtain yellow solid. This solid was recrystallized from ethyl acetate to obtain yellow crystal, which was sufficiently dried in a vacuum oven at 40° C. to give 41 g (yield: 72%) of the desired product, and its melting point was 172° C.–174° C.

Source