反应详情

5.5 g (15.8 mmole) 1,3,3a,4,7,7a-hexahydro-4-(2-nitrophenyl)-1,3-dioxo-7-phenyl-2H-isoindole and 9.1 g (40.1 mmole) 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) are heated under reflux for 16 hours in 100 ml t-butylbenzene. The solvent is removed in a vacuum and the residue chromatographed on silica gel with toluene/ethyl acetate 3:1. The fraction with the Rf of 0.4 is isolated, stirred with a little hot ethanol, and the crystals formed after cooling are filtered off. After recrystallization from ethyl acetate, one obtains 1,3-dihydro-4-(2-nitrophenyl)-1,3-dioxo-7-phenyl-2H-isoindole in the form of colorless crystals of the mp 224°-226° C.

1. customThe solvent is removed in a vacuum
2. customthe residue chromatographed on silica gel with toluene/ethyl acetate 3:1
3. customThe fraction with the Rf of 0.4 is isolated
4. customthe crystals formed
5. temperatureafter cooling
6. filtrationare filtered off
7. customAfter recrystallization from ethyl acetate, one