反应 #62567

反应方程式

NH4Cl

2-Bromofluorobenzene

furan

dioxolanyl furan

magnesium

→

1-(1,3-dioxolan-2-yl)-1,4-epoxy-1,4-dihydronaphthalene

收率 77.1%

溶剂

THF

THF

反应条件

后处理

1. 1
   workup.ADDITIONAfter the addition
2. 2
   温度refluxing
3. 3
   其他the organic layer separated
4. 4
   萃取the aqueous layer re-extracted with ether
5. 5
   萃取The combined organic extract
6. 6
   洗涤was washed with saturated NH4Cl solution
7. 7
   干燥dried over anhydrous K2CO3 -Na2SO4
8. 8
   浓缩concentrated in vacuo
9. 9
   其他The residue was purified on the Waters Prep 500 HPLC
10. 10
    洗涤eluting with EtOAc/hexane (1:4)

实验过程

2-Bromofluorobenzene (36.0 g, 0.222M) in THF (200 ml) was added dropwise over one hour to a refluxing mixture of the above furan (28.0 g, 0.200M) and magnesium turnings (5.4 g, 0.206M) in dry THF (200 ml) under nitrogen. After the addition was complete, refluxing was continued for one hour. The cooled mixture was then poured onto saturated NH4Cl solution (250 ml), the organic layer separated and the aqueous layer re-extracted with ether. The combined organic extract was washed with saturated NH4Cl solution, dried over anhydrous K2CO3 -Na2SO4 and concentrated in vacuo. The residue was purified on the Waters Prep 500 HPLC using two columns and eluting with EtOAc/hexane (1:4). A total of 33.3 g of 1-(1,3-dioxolan-2-yl)-1,4-epoxy-1,4-dihydronaphthalene was obtained as a pale yellow oil. Crystallization of the oil from hexane gave 32.5 g (75% yield) as white crystals, mp 48°-49° C.

来源