反应详情

A mixture of 1-pyridin-2-ylpiperazine (16 mg, 0.1 mmol, Aldrich), paraformaldehyde (30 mg, 1 mmol), 3,5-dimethoxybenzamide (91 mg, 0.5 mmol, Lancaster), and 42 mg of potassium carbonate (0.3 mmol) in 2 mL absolute ethyl alcohol was heated to reflux under nitrogen overnight. The mixture was cooled to room temperature, filtered, and the solvent was removed under reduced pressure. The residue was purified by flash column chromatography on silica gel (10% methanol:ethyl acetate) to give 38.5 mg (72%) pure compound. 1H NMR (500 MHz, DMSO-d6) δ 2.59 (t, J=4 Hz, 4H), 3.48 (t, J=4 Hz, 4H), 3.78 (s, 6H), 4.20 (d, J=5 Hz, 1H), 6.62 (m, 2H), 6.81 (d, J=6 Hz, 1H), 7.03 (s, 2H), 7.50 (t, J=6 Hz, 1H), 8.10 (d, J=5 Hz, 1H), 8.78 (t, J=5 Hz, 1H); MS (ESI/APCI−) m/e 355 (M−H)+.

1. temperaturewas heated
2. temperatureto reflux under nitrogen overnight
3. filtrationfiltered
4. customthe solvent was removed under reduced pressure
5. customThe residue was purified by flash column chromatography on silica gel (10% methanol:ethyl acetate)