Blue-/near-infrared light-triggered photochromism in a reinforced acceptor-acceptor type dithienylethene with aggregation-induced emission

The development of photochromic dithienylethene (DTE) derivatives activated by visible light, particularly those exhibiting aggregation-induced emission (AIE) properties, is highly sought after for applications in photoelectric functional materials and biological systems. In this study, we rationally designed and successfully synthesized a novel cyanostilbene- and nitro-functionalized DTE derivative (6) featuring a reinforced acceptor (A)-DTEacceptor (A) structural motif. Each of the two cyanostilbene fragments bearing nitrobenzene groups imparts both electron-withdrawing effects and AIE characteristics, thereby ensuring efficient visible light-driven photochromic performance. The chemical structure of compound 6 was characterized using standard techniques, including 1H NMR, 13C NMR, and HRMS. As anticipated, the resulting DTE (6) demonstrates efficient photochromism in various solvents when alternately irradiated with blue light (lambda = 460-470 nm) and near-infrared (NIR) light (lambda = 730-740 nm). Prior to blue light irradiation, the AIE performance and solid-state luminescence behavior were assessed. Furthermore, DTE (6) exhibits enhanced photoswitching behavior within a poly (methyl methacrylate) (PMMA) film. The experimental findings are corroborated by density functional theory (DFT) calculations. Ultimately, this derivative has been successfully employed for information recording and erasing, thereby demonstrating its potential for information storage and encryption.