反应详情

5-Bromo-benzofuran-2-carboxylic acid (0.346 g) in THF (7 mL) was treated with carbonyldiimidazole (0.214 g) and stirred at ambient temperature for 2 h whereupon methyl-piperazine (0.129 g) was added. The mixture was stirred at ambient temperature for 18 h and then concentrated under reduced pressure. The residue was dissolved in dichloromethane and washed with saturated sodium bicarbonate solution, whereupon the organic portion was separated out, dried over sodium sulfate and filtered. The solvent was evaporated, and the residue was purified via silica gel chromatography (5% 2 M ammonina in methanol/dichloromethane) to afford the title compound (0.222 g). 1H NMR (400 MHz, CDCl3): δ 7.75 (d, J=1.9 Hz, 1H), 7.45 (dd, J=8.8, 1.9 Hz, 1H), 7.37 (d, J=8.8 Hz, 1H), 3.83 (br s, 4H), 2.48 (t, J=4.8 Hz, 4H), 2.33 (s, 3H). 13C NMR (400 MHz, CDCl3) δ 159.4, 153.4, 150.3, 129.6, 129.0, 124.9, 116.8, 113.5, 111.3, 55.3, 54.9, 46.8, 46.1, 42.9.

1. additionwas added
2. concentrationconcentrated under reduced pressure
3. dissolutionThe residue was dissolved in dichloromethane
4. washwashed with saturated sodium bicarbonate solution, whereupon the organic portion
5. customwas separated out
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. customThe solvent was evaporated
9. customthe residue was purified via silica gel chromatography (5% 2 M ammonina in methanol/dichloromethane)