反应详情

温度

-78 °C

To a stirred solution of 4-(1-methylethyl)-5-(4-methylthiophenyl)-1-(α-ethoxyethyl)imidazole (12.0 g, 0.04 mole) in 150 ml of dry tetrahydrofuran was added 6.85 ml of tetramethylethylenediamine (0.045 moles). The reaction was cooled to -78° C. and 39.47 ml of 1.6M n-butyl lithium in hexane was added dropwise. After stirring the mixture for 20 minutes, 15.45 g of [1,1-di(trifluoromethyl)methyleneamino]-trimethylsilane was added dropwise. The reaction mixture was stirred an additional hour, warmed to 0° C. and 140 ml of saturated aqueous sodium bicarbonate solution was added dropwise. The reaction was warmed to room temperature and the layers were separated. The aqueous layer was extracted with ethyl acetate. The organic layers were combined and concentrated and the residue was stirred overnight in 260 ml of ethanol and 260 ml of 2N aqueous hydrochloric acid. The ethanol was evaporated and the aqueous was extracted with ether (3×), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The product was purified by flash chromatography on silica gel (92:8 hexane/ethyl acetate) to afford 2.67 g of a white crystalline solid, m.p. 105°-107° C.

1. stirringThe reaction mixture was stirred an additional hour
2. temperaturewarmed to 0° C.
3. temperatureThe reaction was warmed to room temperature
4. customthe layers were separated
5. extractionThe aqueous layer was extracted with ethyl acetate
6. concentrationconcentrated
7. stirringthe residue was stirred overnight in 260 ml of ethanol
8. customThe ethanol was evaporated
9. extractionthe aqueous was extracted with ether (3×)
10. dry with materialdried over anhydrous magnesium sulfate
11. filtrationfiltered
12. concentrationconcentrated in vacuo
13. customThe product was purified by flash chromatography on silica gel (92:8 hexane/ethyl acetate)