Реакция #2028902

Уравнение реакции

THF

4-ethoxy-2,2′,3,3′-tetrafluorobiphenyl

sec-butyllithium

→

4-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-carboaldehyde

Выход 70.0%

Растворители

N,N,-dimethylformamide

Условия реакции

Обработка

1. 1
   Другоеprepared by means of a conventional coupling reaction in a reaction vessel under an atmosphere of nitrogen
2. 2
   Температураthe reaction mixture was warmed slowly to room temperature
3. 3
   ДругоеThe reaction mixture was quenched with a saturated aqueous solution of ammonium chloride, and water (500 ml)
4. 4
   workup.ADDITIONwas added
5. 5
   Другоеto give two layers
6. 6
   ЭкстракцияThe water layer was extracted with toluene (200 ml) twice
7. 7
   Промывкаthe combined organic layer was washed with water
8. 8
   Сушкаdried over anhydrous magnesium sulfate
9. 9
   workup.DISTILLATIONThe solvent was distilled off under reduced pressure
10. 10
    workup.ADDITIONThe residue was treated with silica gel chromatography (silica gel: 30 g, eluent: toluene)

Методика

THF (400 ml) was added to 4-ethoxy-2,2′,3,3′-tetrafluorobiphenyl (6) (39.25 g) prepared by means of a conventional coupling reaction in a reaction vessel under an atmosphere of nitrogen. The solution was cooled to −65° C. or lower, and sec-butyllithium (1.08 M in cyclohexane and n-hexane; 141.3 ml) was added dropwise. After the reaction mixture had been stirred at −65° C. for another 1 hour, N,N,-dimethylformamide (21.2 g) was added dropwise, and the reaction mixture was warmed slowly to room temperature. The reaction mixture was quenched with a saturated aqueous solution of ammonium chloride, and water (500 ml) was added to give two layers. The water layer was extracted with toluene (200 ml) twice, and the combined organic layer was washed with water and then dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure. The residue was treated with silica gel chromatography (silica gel: 30 g, eluent: toluene) to give 4-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-carboaldehyde (7) (30 g) in 70% yield.

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