Controlled Fabrication and Characterization of Coronene Diimide‐Based Insoluble Thin Films Produced by Photoinduced Cyclization

Abstract An insoluble thin film of a coronene diimide (CDI) derivative was fabricated from a soluble precursor of perylene diimide (PDI) by photoirradiation. We prepared a 1,7‐diarylated PDI ( TP‐PDI ) that can be converted into a coronene diimide ( TP‐CDI ) derivative via a Scholl‐type photocyclization reaction. This reaction was accompanied by structural changes from a twisted structure to a π‐extended planar molecule. It was found that this photoconversion reaction occurs for both solution‐based and thin‐film‐based reactants investigated by the changes of UV‐vis absorption spectra and 1 H NMR spectra. The photocyclization reactions were found to proceed smoothly in polar solvents. In the thin‐film state, the solvent vapor annealing method is a key process for achieving photoconversion reaction. Additionally, the fabrication of multi‐layered thin films was achieved without undesirable dissolution of the underlying layers because of different solubilities of TP‐PDI and TP‐CDI .