Light-Driven Molecular Dynamics in Perylenes with Medium-Controlled Emission

Highly fluorescent light emitters with medium-tunable clear colors were obtained from the skeleton of perylenedicarboximide by the attachment of donor-substituted aryl groups at the peri-position. The 4-methoxynaphthyl derivative 3a is preferred because of its strong solvatochromism in fluorescence where a mechanism of incomplete PLICT is made responsible both for the large Stokes' shift and the strong medium influence on fluorescence, allowing the fine tuning of color.