反应详情

温度

-40 °C

1-(Diethoxymethyl)imidazole (76.0 g, 446 mmol) and N,N,N,N-tetramethylethylene diamine (67.6 mL, 446 mmol) were dissolved in 2-methyltetrahydrofuran (400 ml) and cooled to −40° C., under nitrogen. n-Butyl lithium (2.5M in hexane, 180 ml, 446 mmol) was added slowly maintaining the reaction temperature at <−25° C. throughout. The reaction mixture was stirred for an hour and allowed to warm to 0° C., after which 2,3-dimethylacetophenone (44.00 g, 297.00 mmol) was added whilst maintaining the reaction temperature at <15° C. throughout. The reaction was stirred at room temperature overnight and then quenched with aqueous hydrochloric acid (2N, 1 l). The mixture was extracted with ethyl acetate (500 ml) and to the aqueous layer was added sodium carbonate. The aqueous layer was further extracted with ethyl acetate (800 ml) and the combined extracts were washed with water (500 ml), dried (MgSO4) and concentrated in vacuo to give the title compound (48.9 g).

1. temperaturemaintaining the reaction temperature at <−25° C. throughout
2. temperatureto warm to 0° C.
3. temperaturewhilst maintaining the reaction temperature at <15° C. throughout
4. stirringThe reaction was stirred at room temperature overnight
5. customquenched with aqueous hydrochloric acid (2N, 1 l)
6. extractionThe mixture was extracted with ethyl acetate (500 ml) and to the aqueous layer
7. additionwas added sodium carbonate
8. extractionThe aqueous layer was further extracted with ethyl acetate (800 ml)
9. washthe combined extracts were washed with water (500 ml)
10. dry with materialdried (MgSO4)
11. concentrationconcentrated in vacuo