A photochromic diarylethene dyad based on perylene diimide

A new photochromic diarylethene dyad based on perylene diimide (PDI-DTE) has been synthesized. The photochromic reaction of PDI-DTE induced the significant change of the absorption spectra and fluorescence intensity. The color of PDI-DTE in THF solution was not changed obviously upon ultraviolet irradiation, while the fluorescence intensity is increased unexpectedly with the photochromic cyclization of the diarylethene units. With not visible change of color accompanied to the enhanced fluorescence, PDI-DTE can be potentially applied to anti-counterfeiting technology.