反应详情

温度

-35 °C

To a solution of diisopropylamine (0.28 mL, 2.0 mmol) in dry tetrahydrofuran (3 mL) at 5° C. was added n-butyllithium (2.5 M solution in hexanes, 1 mL, 2.5 mmol). The resulting mixture was allowed to stir for 30 min. Meanwhile, 2-[trans-4-(4-nitro-3-trifluoromethyl-phenylamino)-cyclohexyloxy]-1-[4-(4-trifluoromethyl-phenyl)-piperazin-1-yl]-ethanone (287 mg, 0.5 mmol, prepared in accordance with Example 11) was dissolved in dry tetrahydrofuran (2 mL). The solution was then cooled to −35° C. To the cooled solution was added an aliquot from the freshly prepared lithium diisopropylamide solution (1.8 mL). Stirring was continued for another 30 min. Methyliodide (37 μL, 0.6 mmol) was then added, and the mixture was allowed to attain −10° C. over 1 hr. Saturated ammonium chloride solution was then added (3 mL), and the mixture warmed to room temperature and acidified to a pH of 3 with 1 N HCl. The aqueous solution was then extracted with ethyl acetate (2×15 mL), and the combined organic layers were washed with brine (2×5 mL), dried over magnesium sulfate, and concentrated. Purification by column chromatography (Ethyl acetate/cyclohexanes, 4:1) afforded the desired product as an orange solid (152 mg, 52% yield). The structure was confirmed using Protocol I-B. Calculated mass=589; observed mass=589; HPLC retention time=5.82 min.

1. stirringStirring
2. waitwas continued for another 30 min
3. waitto attain −10° C. over 1 hr
4. temperaturethe mixture warmed to room temperature
5. extractionThe aqueous solution was then extracted with ethyl acetate (2×15 mL)
6. washthe combined organic layers were washed with brine (2×5 mL)
7. dry with materialdried over magnesium sulfate
8. concentrationconcentrated
9. customPurification by column chromatography (Ethyl acetate/cyclohexanes, 4:1)