Facile synthesis and characterization of new photochromic trans-dithienylethenes functionalized with pyridines and fluorenes.

Three symmetrical and unsymmetrical trans-dithienylethenes functionalized with pyridines and fluorenes have been synthesized by a facile one-pot procedure, and their characteristics and photochromism were investigated. Their fluorescent intensity was efficiently regulated by a photochromic switch using alternative irradiation with UV light and visible light. Moreover, by protonation and complexation, the pyridyl-substituted compounds also showed excellent photoswitching properties with distinguishable color changes. These characteristics are expected to be applicable to potential multi-addressable photoswitch and erasable optical data processing technologies.