Reaktion #687282

Reaktionsgleichung

magnesium

2-bromo-9-fluorenone

2-bromobiphenyl

→

9-(biphenyl-2-yl)-2-bromo-9-fluorenol

Ausbeute 90.0%

Lösungsmittel

diethyl ether

diethyl ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe flask was evacuated
2. 2
   Temperaturof heating
3. 3
   workup.ADDITION5 mL of diethyl ether and several drops of dibromoethane were added
4. 4
   Temperaturthe mixture was refluxed for 3 hours
5. 5
   Temperaturthe mixture was refluxed for 2 hours
6. 6
   workup.STIRRINGstirred at room temperature for about 12 hours
7. 7
   Waschenthe solution was washed twice with saturated ammonia chloride solution
8. 8
   ExtraktionAn aqueous layer was extracted twice with ethyl acetate
9. 9
   Waschenthe solution was washed with a saturated saline solution
10. 10
    TrocknenAfter drying with magnesium sulfate, suction filtration and concentration

Vorschrift

1.26 g (0.052 mol) of magnesium was put in a 100 mL three-necked flask to which a dropping funnel and a Dimroth condenser were connected, and the flask was evacuated. The magnesium was activated by 30 minutes of heating and stirring. After cooling to room temperature, the flask was placed under a nitrogen gas flow. 5 mL of diethyl ether and several drops of dibromoethane were added, and 11.65 g (0.050 mol) of 2-bromobiphenyl dissolved in 15 mL of diethyl ether was slowly delivered from the dropping funnel by drops into the mixture. After the dropping was complete, the mixture was refluxed for 3 hours and made into a Grignard reagent. 11.7 g (0.045 mol) of 2-bromo-9-fluorenone and 40 mL of diethyl ether were put in a 200 mL three-necked flask to which a dropping funnel and a Dimroth condenser were connected. To this reaction solution, the synthesized Grignard reagent was slowly delivered by drops from the dropping funnel. After the dropping was complete, the mixture was refluxed for 2 hours, and then stirred at room temperature for about 12 hours. After the reaction was complete, the solution was washed twice with saturated ammonia chloride solution. An aqueous layer was extracted twice with ethyl acetate and combined with an organic layer, and the solution was washed with a saturated saline solution. After drying with magnesium sulfate, suction filtration and concentration were conducted, and a solid of 9-(biphenyl-2-yl)-2-bromo-9-fluorenol was obtained, weighing 18.76 g in a yield of 90%.

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