Electron-Transfer Reduction Properties and Excited-State Dynamics of Benzo[ghi]peryleneimide and Coroneneimide Derivatives

Abstract

A series of benzo[ghi]perylene and coronene derivatives substituted by electron-withdrawing imide and ester groups were systematically synthesized considering (i) number of imide and ester groups, (ii) five- and six-membered imide groups, and (iii) the peripheral positions. The spectroscopic, electrochemical, and photophysical properties of these molecules were investigated in full detail by steady-state and time-resolved spectroscopy, cyclic voltammetry, quantum yield measurements of fluorescence and intersystem crossing, electron spin resonance (ESR), and density functional theory calculations. The synthetic introduction of proper substituents on the polycyclic aromatic hydrocarbon ring therefore enables us to successfully control the electrochemical and photophysical behaviors. The steady-state absorption and fluorescence spectra also become red-shifted and broadened as compared to those of reference unsubstituted benzo[ghi]perylene and coronene. Regarding the electrochemistry, with an increase in the ...