Host–Guest Complexation-Induced Aggregation Based on Pyrene-Modified Cyclodextrins for Improved Electronic Circular Dichroism and Circularly Polarized Luminescence

Abstract

Several γ-cyclodextrin (CD) derivatives mono- or di-substituted by pyrenes at the primary rim of the CD were demonstrated to aggregate into nano-strips in aqueous solutions, with the pyrene moieties interpenetrating into γ-CD cavities. The hydrophobic complexation-induced aggregation provides a rigid chiral environment for the pyrenes and leads to significant electronic circular dichroism (ECD) and circularly polarized luminescence (CPL) activities, giving unprecedently high gabs and glum values up to 4.3×10−2 and 5.3×10−2, respectively. The aggregates lead to excimer emission with high quantum yields and show BCPL and BiCPL up to 338. 6 M−1 cm−1 and 169.3 M−1 cm−1, respectively.