Synthesis And Properties Study Of Donor-Acceptor Molecules Based On Asymmetrical Perylene Diimides

Perylene diimide derivatives (PDI) with large rigid planes and π-π conjugated structures exhibit excellent photochemical and thermal stabilities, high fluorescence quantum yields, as well as good electron affinity and electron accepting ability, which have received significant attentions and have been widely used in many fields, such as organic solar cells, photoconductor, electroluminescence, supramolecular self-assembly and biological fluorescent probes. However, especially in organic photovoltaic fields, the poor solubility have restricted the applications of PDI. The introduction of alkyl chains to the imide position of perylene derivatives, which can be used to synthetise asymmetrical perylene monoanhydride monoimide, the key intermediats to synthetise asymmetrical perylene diimides, could keep the plane structures and enhance the solubility of PDI.In this paper, we have designed and synthesized two donor-acceptor asymmetrical perylene diimides, PDI-ATPA and PDI-TATPA, using branched alkyl chain substituted asymmetrical perylene monoanhydride monoimide (AsPDA-I) as the electron-accepting species and different functional triphenylamines, ATPA and TATPA, as the electron-donating moieties, respectively. PDI-ATPA and PDI-TATPA exhibit high molar extinction coefficients, different color and luminescence behaviors in solution. In addition, compared to the structure of linear asymmetrical perylene diimide PDI-ATPA, PDI-TATPA shows a propeller-shaped structure with highly regularity, which has caused the self-assembly behavior of PDI-TATPA easily occur in solution. Besides, molecular simulations were carried out to elucidate the electronic structures, molecular orbitals, energy levels and dipole moments of our synthesized asymmetrical perylene diimides.Star-shaped molecule PDI-TATPA provides a new monomer for supramolecular self-assembly and has the potential applied value in organic photoelectric devices.