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Updated: Jun 7, 2025

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Construction and Circularly Polarized Luminescence of Thiophene-Based Multiple Helicenes
Lanping Dang1, Wan Xu1, Shuai Qiu1
1Institute of Nanoscience and Engineering, Henan University, Kaifeng 475004, China.
Abstract:
Thiophene-based monohelicene (TS[7]H), triple helicenes (TT[7]H), and hexapole helicenes (TH[7]H) were synthesized via oxidative photocyclization and cascade Suzuki/intramolecular cyclization as the crucial steps. The enantiomers of TS[7]H, TT[7]H-2, and TH[7]H exhibited circularly polarized luminescence (CPL), and the luminescence dissymmetry factors (glum) gradually increased from -5.1 × 10-4 to -2.0 × 10-3 with an increase in multiplicity from TS[7]H to TH[7]H. In addition, TS[7]H, TT[7]H, and TH[7]H displayed a second-level long afterglow at 77 K.
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