反应详情

温度

70 °C

To conc. sulfuric acid (3 ml) is added sodium nitrite (0.3 g). The mixture is stirred at 70° C. for 10 minutes and then cooled to below 40° C. and thereto a solution of 2,3,5-trifluoro-4-methylaniline (0.48 g) in acetic acid (5 ml) is added dropwise below 40° C. After stirring for 30 minutes, the reaction mixture is added dropwise to a solution of copper (I) chloride (1.04 g) in conc. hydrochloric acid (10.4 ml) and the mixture is stirred at 80° C. for 30 minutes and then cooled. The resultant mixture is poured into ice-water, extracted with dichloromethane, and the extract is washed with water and dried. The solvent is distilled off under reduced pressure and purified by silica-gel column-chromatography (eluent; dichloromethane: n-hexane=1:4) to give 2,3,6-trifluoro-4-chlorotoluene (0.22 g).

1. temperaturecooled to below 40° C.
2. stirringAfter stirring for 30 minutes
3. stirringthe mixture is stirred at 80° C. for 30 minutes
4. temperaturecooled
5. extractionextracted with dichloromethane
6. washthe extract is washed with water
7. customdried
8. distillationThe solvent is distilled off under reduced pressure
9. custompurified by silica-gel column-chromatography (eluent; dichloromethane: n-hexane=1:4)