Synthesis and photoswitching behavior of donor-acceptor type dithienylethene derivatives modified by diestervinyl moieties

Abstract

Developing novel dithienylethenes (DTEs) with excellent photochromic performance has attracted wide attention due to the potential applications in the field of photoelectric functional materials. Herein, two new donor-acceptor type DTE derivatives (1a and 1b) have been developed, which were decorated by electron-donating dimethylaminobenzene (or anisole) and electron-withdrawing diestervinyl moieties on DTE core. Their chemical structures were well characterized by 1H NMR, 13C NMR and HRMS (ESI). As expected, they presented solvent-dependent photochromic behaviors with good fatigue resistance in the different polar solvents (toluene, chloroform and dimethyl sulfoxide) upon irradiation with UV and visible light. Moreover, these results implied a significantly enhanced solvent dependence of photochromism with increasing electron donor capacity in this D-DTE-A system. Furthermore, they also displayed excellent photochromism and fluorescence switching behavior in the PMMA film upon the same irradiation conditions. The corresponding experimental results were further validated by DFT calculations. In view of the above, they can be utilized as a novel D-A type DTE derivatives integrated into the future smart photoelectric materials.