A Star-Shaped Molecule with Low-Lying Lowest Unoccupied Molecular Orbital Level, n-Type Panchromatic Electrochromism, and Long-Term Stability

An electron-deficient star-shaped molecule based on anthraquinone imide was synthesized and characterized. It showed high electron accommodating capacity and strong electron-withdrawing ability with a low-lying lowest unoccupied molecular orbital (LUMO) of -4.10 eV. In addition, it exhibited panchromatic electrochromism attributed to the simultaneous presence of pi*-pi* transitions and intervalence charge transfer (IV-CT) upon one-electron reduction, and revealed long-term stability in electron gain and loss due to the proper LUMO energy level and ordered intermolecular assembly.