反应详情

To 1 g (5.2 mmol) of compound 3, dissolved in 10 ml of MeOH, was added 0.1 ml of piperidine, 0.1 ml of acetic acid and 3 ml of an aqueous formaldehyde solution (37% formaldehyde in water). The mixture was heated to reflux for 48 hour. The mixture was cooled and concentrated in vacuo. Ethyl acetate was added and the organic layer was washed with a 5% NaHCO3 solution, dried (Na2SO4), filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography (diethyl ether/PE 1/1) to give compound 4 as an oil (1.05 g, 95%). 1H-NMR (200 MHz, CDCl3): δ 8.94 (d, J=2 Hz, 1H), 8.76 (d, J=5 Hz, 2 Hz, 1H), 8.05 (dt, J=8 Hz, 2 Hz, 1H), 7.46-7.35 (m, 1H), 5.94 (s, 1H), 5.64 (s, 1H), 2.48 (bt, J=7 Hz, 2H), 1.60-1.25 (m, 6H), 0.99-0.82 (m, 3H).

1. temperatureThe mixture was heated
2. temperatureto reflux for 48 hour
3. temperatureThe mixture was cooled
4. concentrationconcentrated in vacuo
5. additionEthyl acetate was added
6. washthe organic layer was washed with a 5% NaHCO3 solution
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe resulting residue was purified by flash chromatography (diethyl ether/PE 1/1)