反应详情

To a mixture of 2-Amino-4-methylpyridine (21.6 g, 0.2 mol) and phthalic anhydride (29.6 g, 0.2 mol) in toluene (160 ml), was added triethylamine (2.8 ml, 0.02 mol). The mixture was refluxed for 5 hr. After cooling to room temperature, the mixture was evaporated in vacuo and the residue was suspended in acetic anhydride (250 ml). The mixture was then heated to reflux for 4 hr until the solid dissolves completely. After cooling to room temperature, white precipitate was collected by filtration and washed with acetic anhydride and hexane, and dried in high vacuo to give 26.6 g (56%) of 2-(4-methyl-pyridin-2-yl)-isoindole-1,3-dione as a white solid. 1H NMR (200 MHz, CDCl3) δ 2.45 (3H, s), 7.18 (1H, d, J=5.0 Hz), 7.25 (1H, s), 7.76-7.99 (4H, m), 8.53 (1H, d, J=5.0 Hz). m/z (EI) 238 (M+).

1. temperatureThe mixture was refluxed for 5 hr
2. customthe mixture was evaporated in vacuo
3. temperatureThe mixture was then heated
4. temperatureto reflux for 4 hr until the solid
5. dissolutiondissolves completely
6. temperatureAfter cooling to room temperature
7. filtrationwhite precipitate was collected by filtration
8. washwashed with acetic anhydride and hexane
9. customdried in high vacuo