Circularly Polarized Luminescence from π‐Conjugated Chiral Perylene Diimide Luminophores: The Bay Position Effect

Abstract

AbstractThree types of chiral perylene diimide luminophores bearing ethynyl, phenyl, and ethynylphenyl substituents (BPP‐Ethy, BPP‐Ph, and BPP‐EthyPh) at the bay positions were prepared. The chiroptical properties of the compounds in their solution (in CHCl3) and polymethyl methacrylate (PMMA)‐film solid states were investigated. Similar to the chiral BPP molecules bearing no substituents at the bay position, BPP‐Ethy, BPP‐Ph, and BPP‐EthyPh luminophores emitted no clear circularly polarized luminescence (CPL) in CHCl3 solution. In contrast, the chiral BPP‐Ethy, BPP‐Ph, and BPP‐EthyPh luminophores exhibited intense aggregation‐induced enhanced CPL (AIEnh‐CPL) in the PMMA‐film state; BPP exhibited similar properties. Although the four luminophores were of the same absolute configurations, the CPL signs of the chiral BPP‐EthyPh were opposite to those of BPP, BPP‐Ethy, and BPP‐Ph. This could be attributed to the effects of the substituents at the bay position.