反应详情

In a dry round bottom flask, 1,2,3-benzotriazin-4(3H)-one (50 g), ethyl 4-bromobutanoate (86.2 g) and potassium carbonate (141 g) were taken and dissolved in dimethylformamide (350 mL) and heated to 60° C. to 70° C. for 3 to 4 hours. After cooling to room temperature, water was added to the reaction mixture and extracted with ethyl acetate. The combined organic layer was washed with water and brine and dried over anhydrous sodium sulfate. Solvents were evaporated under reduced pressure and the crude product was purified by silica gel flash column chromatography over silica gel using 20% ethylacetate in hexane as eluant to afford the title compound (68 g).

1. temperatureheated to 60° C. to 70° C. for 3 to 4 hours
2. extractionextracted with ethyl acetate
3. washThe combined organic layer was washed with water and brine
4. dry with materialdried over anhydrous sodium sulfate
5. customSolvents were evaporated under reduced pressure
6. customthe crude product was purified by silica gel flash column chromatography over silica gel using 20% ethylacetate in hexane as eluant