反应详情

4-(4-Trifluoromethylphenyl)tetrahydropyran-2-one (995 mg) derived by the same method as in Preparation Example 2-10 from 4-(trifluoromethyl)phenylboronic acid (5.29 g) and 5,6-dihydro-2H-pyran-2-one was dissolved in tetrahydrofuran (10 mL). The solution was added dropwise at −78° C. to a lithium diisopropylamide solution previously prepared from n-butyllithium (3.91 mL) and diisopropylamine (1.46 mL) in tetrahydrofuran (30 mL). After stirring at the same temperature for 30 minutes, iodomethane (760 μL) and hexamethylphosphoramide (1.77 mL) were added and stirring was continued. After stirring for 30 minutes, the reaction solution was gradually heated to room temperature over three hours and 20 minutes. The reaction was terminated with saturated ammonium chloride aqueous solution. The organic layer was washed with brine and then dried over magnesium sulfate. Removal under reduced pressure gave an oil. The oil was purified by silica gel column chromatography (mobile phase:ethyl acetate/heptane=0 to 50%) to obtain the title compound (500 mg).

1. stirringstirring
2. stirringAfter stirring for 30 minutes
3. customThe reaction was terminated with saturated ammonium chloride aqueous solution
4. washThe organic layer was washed with brine
5. dry with materialdried over magnesium sulfate
6. customRemoval under reduced pressure
7. customgave an oil
8. customThe oil was purified by silica gel column chromatography (mobile phase:ethyl acetate/heptane=0 to 50%)