反应详情

温度

-20 °C

To a mixture of 91.1 g (0.5 mole) of xanthene, 176.3 g (1.25 moles) of 4-chlorobutyryl chloride and 3 liters of dry methylene chloride, chilled to -20° C., is slowly added over a 30 minute period 146.7 g (1.1 moles) of aluminum chloride, during which the temperature is maintained below -10° C. Following the addition, the reaction temperature is slowly permitted to rise to room temperature and then refluxed for an additional 4 hours. Upon cooling, the mixture is decomposed by cautiously pouring into 2 liters of an ice-water mixture. The liquid layers are separated and the aqueous layer extracted with methylene chloride. The combined organic layers are evaporated to a small volume and cooled. The resulting 2,7-bis(4-chlorobutyryl)xanthene so obtained is recrystallized from acetone to yield the desired product having a m.p. 131°-2° C.

1. temperatureduring which the temperature is maintained below -10° C
2. additionthe addition
3. customto rise to room temperature
4. temperaturerefluxed for an additional 4 hours
5. temperatureUpon cooling
6. customThe liquid layers are separated
7. extractionthe aqueous layer extracted with methylene chloride
8. customThe combined organic layers are evaporated to a small volume
9. temperaturecooled