Reaktion #2028908

Reaktionsgleichung

Dichloromethane

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

Triethylsilane

→

5-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-2-(4-propylcyclohexyl)tetrahydropyran

Ausbeute 36.1%

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared in the tenth step
2. 2
   Sonstigeto give two layers
3. 3
   WaschenThe organic layer was washed with water
4. 4
   Trocknendried over anhydrous magnesium sulfate
5. 5
   workup.DISTILLATIONThe solvent was distilled off under reduced pressure
6. 6
   SonstigeThe residue was purified by silica gel chromatography (silica gel: 200 g, eluent: heptane/ethyl acetate=80/20 by volume)
7. 7
   Sonstigeby recrystallization (heptane/ethyl acetate=90/10 by volume)

Vorschrift

Dichloromethane (30 ml) was added to 3-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-6-(4-propylcyclohexyl)tetrahydropyran-2-ol (12) (2.29 g) prepared in the tenth step. Triethylsilane (1.93 g) and a boron trifluoride-diethyl ether complex (2.37 g) were added dropwise to the solution at −30° C. After 3 hours of stirring, water (30 ml) was added to give two layers. The organic layer was washed with water, 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=80/20 by volume) and then by recrystallization (heptane/ethyl acetate=90/10 by volume) to give 5-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-2-(4-propylcyclohexyl)tetrahydropyran (13) (0.8 g) in 36% yield.

Quelle