反应详情

Toluene (20 ml) was added to 3-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-6-(4-propylcyclohexyl)tetrahydropyran-2-one (11) (2.35 g) prepared in the ninth step. A toluene solution of diisobutylaluminum hydride (0.99 M; 9.6 ml) was added dropwise at −50° C. or lower, and the stirring was continued for 3 hours. The reaction mixture was poured into a 10% aqueous solution of formic acid (50 ml) to give two layers. The water layer was extracted with toluene (20 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 to leave 3-(4′-ethoxy-2,2′,3,3′-tetrafluorobiphenyl-4-yl)-6-(4-propylcyclohexyl)tetrahydropyran-2-ol (12) (2.29 g) in 99% yield.

1. customprepared in the ninth step
2. customto give two layers
3. extractionThe water layer was extracted with toluene (20 ml) twice
4. washthe combined organic layer was washed with water
5. dry with materialdried over anhydrous magnesium sulfate
6. distillationThe solvent was distilled off under reduced pressure