반응 #1964662

반응 방정식

[2-trifluoromethylpyridin-5-yl]boronic acid

caesium carbonate

dichloromethane

4-trifluoromethanesulphonyloxycarbazole

→

4-[6-(trifluoromethyl)pyridin-3-yl]-9H-carbazole

수율 49.6%

용매

dioxane

water

반응 조건

후처리

1. 1
   온도The reaction mixture is refluxed for 5 hours
2. 2
   여과filtered through celite and
3. 3
   농축concentrated under reduced pressure
4. 4
   기타The residue is subsequently purified by silica gel chromatography, elution
5. 5
   workup.ADDITIONbeing carried out with a mixture of cyclohexane and ethyl acetate (85/15 by volume) so as

실험 절차

0.96 g of [2-trifluoromethylpyridin-5-yl]boronic acid, 4.55 g of caesium carbonate and 0.13 g of 1,1′-bis(diphenylphosphino)ferrocenepalladium(II) dichloride as a complex with dichloromethane (1/1) [PdCl2(dppf).CH2Cl2] are successively added, under argon, to a solution of 1.1 g of 4-trifluoromethanesulphonyloxycarbazole, obtained in stage 1 of Example 1, in a mixture of 50 ml of dioxane and 17 ml of water. The reaction mixture is refluxed for 5 hours, filtered through celite and concentrated under reduced pressure. The residue is subsequently purified by silica gel chromatography, elution being carried out with a mixture of cyclohexane and ethyl acetate (85/15 by volume) so as to give 0.54 g of 4-[6-(trifluoromethyl)pyridin-3-yl]-9H-carbazole in the form of a pale yellow oil, the characteristics of which are the following:

출처