反応 #2028902

反応方程式

THF

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

sec-butyllithium

→

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

収率 70.0%

溶媒

N,N,-dimethylformamide

反応条件

後処理

1. 1
   その他prepared by means of a conventional coupling reaction in a reaction vessel under an atmosphere of nitrogen
2. 2
   温度the reaction mixture was warmed slowly to room temperature
3. 3
   その他The reaction mixture was quenched with a saturated aqueous solution of ammonium chloride, and water (500 ml)
4. 4
   workup.ADDITIONwas added
5. 5
   その他to give two layers
6. 6
   抽出The water layer was extracted with toluene (200 ml) twice
7. 7
   洗浄the combined organic layer was washed with water
8. 8
   乾燥dried 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)

実験手順

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.

出典