反应详情

A mixture of 4-hydroxy-3-methylacetophenone (14.5 g, 96 mmol), K2CO3 (17.5 g, 144 mmol), and 1,3-dibromopropane (30 g, 144 mmol) in acetonitrile (400 ml) was heated at reflux for 6 hours. At the end of the reaction, the solvent was removed on a rotary evaporator, and the crude solid was extracted into dichloromethane (750 ml). The insoluble inorganics were filtered off. The dichloromethane solution was concentrated again to a crude oil (34.5 g). Purification was effected by flash chromatography over a silica gel column (SiO2, 150 g; eluted with 7:3 hexane:dichloromethane, 2 1; and dichloromethane 2 1). The material thus purified weighed 14.6 g (56%) and was recrystallized from ethanol. Recrystallization again from ethanol gave analytically pure 1-[4-(3-bromopropoxy)-3-methylphenyl]ethanone, m.p.=59°-61° C.

1. temperaturewas heated
2. temperatureat reflux for 6 hours
3. customAt the end of the reaction
4. customthe solvent was removed on a rotary evaporator
5. extractionthe crude solid was extracted into dichloromethane (750 ml)
6. filtrationThe insoluble inorganics were filtered off
7. concentrationThe dichloromethane solution was concentrated again to a crude oil (34.5 g)
8. customPurification
9. washwas effected by flash chromatography over a silica gel column (SiO2, 150 g; eluted with 7:3 hexane:dichloromethane, 2 1; and dichloromethane 2 1)
10. customThe material thus purified
11. customwas recrystallized from ethanol
12. customRecrystallization again from ethanol