反应详情

温度

20 °C

A solution of 2,3,4-trifluoro-N-[1-ethoxy-2-(ethoxycarbonyl)ethylidene]aniline (122 g) in phenyl ether (120 cc) is introduced dropwise in the course of 25 minutes and with stirring into phenyl ether (600 cc) at a temperature in the region of 250° C. while the ethanol formed is removed by distillation. After stirring for 15 minutes at the same temperature, the solution is cooled to approximately 20° C. and treated with n-hexane (750 cc). The precipitate formed is drained and washed with n-hexane (3×200 cc). 2-Ethoxy-6,7,8-trifluoro-4-hydroxyquinoline (69.5 g) is obtained in the form of a beige solid, m.p. 171° C., which is used without further purification for the subsequent steps.

1. customformed
2. customis removed by distillation
3. additiontreated with n-hexane (750 cc)
4. customThe precipitate formed
5. washwashed with n-hexane (3×200 cc)