反应详情

A mixture of 3-(ethylamino)-5-(pyridin-4-yl)thiophene-2-carboxylic acid (0.415 g, 1.67 mmol), ammonium chloride (0.893 g, 16.7 mmol), triethylamine (2.35 mL, 16.7 mmol) and DMF (10 mL) was stirred for 5 min. Then, 1-hydroxybenzotriazole (0.676 g, 5.00 mmol) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (0.956 g, 5.00 mmol) were added and stirring was continued for 3 days. The mixture was then poured into sat. aqueous sodium hydrogen carbonate (100 mL) and water (60 mL). Extraction with ethyl acetate-tetrahydrofuran (3:1, 2×100 mL), washing with sat. aqueous sodium hydrogen carbonate and brine, drying over magnesium sulfate, filtration and concentration at reduced pressure gave a yellow solid. This solid was triturated with dichloromethane, and the precipitate was collected by filtration to afford the title compound (0.258 g, 62%) as a yellow solid:

1. stirringstirring
2. waitwas continued for 3 days
3. extractionExtraction with ethyl acetate-tetrahydrofuran (3:1, 2×100 mL)
4. washwashing with sat. aqueous sodium hydrogen carbonate and brine
5. dry with materialdrying over magnesium sulfate, filtration and concentration at reduced pressure
6. customgave a yellow solid
7. customThis solid was triturated with dichloromethane
8. filtrationthe precipitate was collected by filtration