Photophysical properties of monocyano-(2-, 3-, and 4-cyano) and dicyano-(3, 4-, 3, 5-, 2, 3-, 2, 4-, 2, 5-, and 2, 6-dicyano) anilines are investigated by fluorescence measurements. All the monocyanoanilines are virtually nonfluorescent in water (quantum yield< 0.01); however, in nonaqueous solvents (cyclohexane, acetonitrile and ethanol), the fluorescence quantum yield is enhanced substantially. In contrast, dicyanoanilines investigated are ...
