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Updated: Sep 25, 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
Synthesis and fluorescence properties of butadiyne-linked linear and cyclic carbazole oligomers
Kazuya Ogawa1, Shohei Tanaka1, Kyosuke Shimura1
1Graduate Faculty of Interdisciplinary Research, University of Yamanashi 4-3-11 Takeda, Kofu Yamanashi 400-8511 Japan kogawa@yamanashi.ac.jp.
Abstract:
Butadiyne-linked linear and cyclic carbazole oligomers were successfully synthesized. The intensity of the emission band in the 0-0 band of the highly planar macrocyclics decreased compared to that of the 0-1 band. Contrary to this, for larger macrocycles having reduced planarity, the intensity of the emission of the 0-0 band increased as in the cases of the linear compounds. This suggests that the emission color of the π-conjugated molecule can be controlled not only by the difference between the cyclic and chain structures but also by the control of the planarity, and is expected to be a new principle for molecular design in the development of fluorescent materials.
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