반응 #539539

반응 방정식

water

lithium bromide

N-ethyl-3-bromocarbazole

benzene

→

N-ethyl-3-(3-bromophenyl)carbazole

수율 29.2%

용매

diethylether

ether

반응 조건

후처리

1. 1
   기타was flame-dried
2. 2
   workup.ADDITION2.4 ml of n-butyl lithium (2.64M hexane solution) was added dropwise
3. 3
   온도After raising the temperature to 0° C.
4. 4
   온도it was cooled again to −78° C.
5. 5
   기타an ether solution of magnesium bromide prepared from magnesium 0.4 g and 1,2-dibromoethane 0.8 g
6. 6
   workup.ADDITIONwas added dropwise
7. 7
   온도After raising the temperature to room temperature
8. 8
   workup.STIRRINGstirring for 12 hours
9. 9
   workup.ADDITIONthis reaction solution was added dropwise into a solution which
10. 10
    기타was prepared
11. 11
    온도cooled at 0° C
12. 12
    workup.STIRRINGAfter stirring for 7 hours
13. 13
    기타partitioned
14. 14
    추출The aqueous phase was extracted twice with 40 ml toluene
15. 15
    세척the combined aqueous phase was washed with water and saturated NaCl aqueous solution
16. 16
    농축concentrated
17. 17
    기타1.61 g of crude product was obtained
18. 18
    기타It was purified with silica gel column chromatography (eluent, hexane:ethyl-acetate=25:1)

실험 절차

1.00 g of N-ethyl-3-bromocarbazole was dissolved in 3.2 ml of dehydrated ether in a Schrenck tube which was flame-dried and argon gas-replaced. This solution was cooled to −78° C., and 2.4 ml of n-butyl lithium (2.64M hexane solution) was added dropwise. After raising the temperature to 0° C., and stirring for 1 hour, it was cooled again to −78° C., an ether solution of magnesium bromide prepared from magnesium 0.4 g and 1,2-dibromoethane 0.8 g was added dropwise. After raising the temperature to room temperature and stirring for 12 hours, this reaction solution was added dropwise into a solution which was prepared by suspending lithium bromide 0.28 g, 3-trifluoromethanesulfoxybromo benzene 0.82 g, and dichloro[1,3-bis(diphenylphosphino)propane]palladium(II) 0.09 g in dehydrated diethylether 2 ml, and cooled at 0° C. After stirring for 7 hours, 20 ml water was added dropwise and partitioned. The aqueous phase was extracted twice with 40 ml toluene, and the combined aqueous phase was washed with water and saturated NaCl aqueous solution, then concentrated, and 1.61 g of crude product was obtained. It was purified with silica gel column chromatography (eluent, hexane:ethyl-acetate=25:1), 0.33 g of N-ethyl-3-(3-bromophenyl)carbazole was obtained.

출처