反应详情

1-(3-Methoxyphenyl)-2-pyridin-4-ylethane-1,2-dione (1.93 g, 8.0 mmol), 4-formylpiperidine-1-carboxylic acid tert-butyl ester (1.7 g, 8.0 mmol) and ammonium acetate (6.2 g, 80 mmol) were dissolved in acetic acid (20 mL) and heated to reflux for 2 hours, then allowed to cool to ambient temperature. The reaction mixture was poured over an ammonium hydroxide (50 mL) and ice mixture, extracted with ethyl acetate (3×125 mL) and the combined organic layers dried over anhydrous magnesium sulfate, filtered and concentrated at reduced pressure. The resulting oil was chromatographed on silica gel eluting with ethyl acetate to give the imidazole as a foam (1.2 g), which was used without further purification.

1. temperatureheated
2. temperatureto reflux for 2 hours
3. extractionextracted with ethyl acetate (3×125 mL)
4. dry with materialthe combined organic layers dried over anhydrous magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated at reduced pressure
7. customThe resulting oil was chromatographed on silica gel eluting with ethyl acetate