Synthesis and theoretical investigation of phenanthrodithiophene diimide

Construction of a phenanthrodithiophene diimide core has been accomplished through photo-induced 6π electrocyclization. It is generated with the formation of anthradithiophene diimide. The product distribution is illuminated by the help of DFT calculations. The discrepancy in the optical and electrochemical properties between both compounds is identified. Time-dependent DFT calculations are carried out, yielding theoretical UV-vis spectra, which agree well with the experimental patterns. Electronic transitions for the two compounds can be clarified. Overall, this study provides a new synthetic approach to accessing phenanthrodithiophene diimide and elucidates the reaction mechanism and optical and electrochemical properties.