Реакция #2028906

Уравнение реакции

2-(trans-4-propyl-cyclohexyl)-oxetane

THF

THF

2-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)acetic acid

n-butyllithium

→

3-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-6-(4-propylcyclohexyl)tetrahydropyran-2-one

Выход 87.0%

Растворители

formic acid

Условия реакции

Обработка

1. 1
   Другоеprepared in the eighth step
2. 2
   workup.ADDITIONAfter the addition
3. 3
   Другоеwas returned to room temperature
4. 4
   ТемператураThe solution was then cooled to −65° C.
5. 5
   workup.ADDITIONAfter the addition
6. 6
   Другоеwas returned to room temperature
7. 7
   Другоеto give two layers
8. 8
   ЭкстракцияThe water layer was extracted with toluene (20 ml) three times
9. 9
   Промывкаthe combined organic layer was washed with water
10. 10
    Сушкаdried over anhydrous magnesium sulfate
11. 11
    workup.DISTILLATIONThe solvent was distilled off under reduced pressure
12. 12
    ДругоеThe residue was purified by silica gel chromatography (silica gel: 200 g, eluent: heptane/ethyl acetate=90/10 by volume)

Методика

THF (50 ml) was added to 2-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)acetic acid (10) (2.0 g) prepared in the eighth step. The solution was cooled to −5° C., and n-butyllithium (1.59 M in n-hexane; 7.66 ml) was added dropwise. After the addition had been completed, the reaction mixture was returned to room temperature, and the stirring was continued for 30 minutes. The solution was then cooled to −65° C., and 2-(trans-4-propyl-cyclohexyl)-oxetane (5) (1.0 g) in a THF (5 ml) solution and a boron trifluoride-diethyl ether complex (0.86 g) were added dropwise. After the addition had been completed, the reaction mixture was returned to room temperature, and a 10% aqueous solution of formic acid (100 ml) was added to give two layers. The water layer was extracted with toluene (20 ml) three times 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 purified by silica gel chromatography (silica gel: 200 g, eluent: heptane/ethyl acetate=90/10 by volume) to give 3-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-6-(4-propylcyclohexyl)tetrahydropyran-2-one (11) (2.35 g) in 86.1% yield.

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