反应详情

A mixture of N-(2-(4-aminophenoxy)ethyl)phthalimide (4.2 g), methylpropionylacetate (1.94 g) and p-toluenesulphonic acid (100 mg) in benzene (95 ml) was stirred and heated at reflux for 3 hours with azeotropic removal of water. Volatile material was then removed by evaporation and the residue was added to a refluxing eutectic mixture of 26.5% v/v diphenyl and 73.5% v/v diphenyl oxide (25 ml). The mixture was heated at reflux for 15 minutes and then cooled to ambient temperature. Hexane (80 ml) was added to the mixture which was triturated to give a solid. The solid was collected by filtration and washed with hexane. Ethyl acetate (70 ml) was added to the solid and the mixture was heated at reflux for 5 minutes and then cooled in an ice-bath. The undissolved solid was collected by filtration and washed with ethyl acetate to give 2-ethyl-6-(2-phthalimidoethoxy)-4-quinolone (2.5 g) as an off white solid, m.p. 168°-171° C.; NMR (d6 -DMSO): 1.24(t, 3H), 2.59(q, 2H), 4.0(t, 2H), 4.28(t, 2H), 5.87(s, 1H), 7.18(dd, 1H), 7.45(m, 2H), 7.84(m, 4H), 11.4(br s, 1H).

1. temperatureheated
2. customVolatile material was then removed by evaporation
3. additionthe residue was added to a refluxing eutectic mixture of 26.5% v/v diphenyl and 73.5% v/v diphenyl oxide (25 ml)
4. temperatureThe mixture was heated
5. temperatureat reflux for 15 minutes
6. additionHexane (80 ml) was added to the mixture which
7. customwas triturated
8. customto give a solid
9. filtrationThe solid was collected by filtration
10. washwashed with hexane
11. additionEthyl acetate (70 ml) was added to the solid
12. temperaturethe mixture was heated
13. temperatureat reflux for 5 minutes
14. temperaturecooled in an ice-bath
15. filtrationThe undissolved solid was collected by filtration
16. washwashed with ethyl acetate