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Updated: Sep 21, 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
Inducing Curvature to Pyracylene upon π-Expansion
John Bergner1,2, Christian Walla1,3, Frank Rominger1
1Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Abstract:
We disclose a successive π-expansion of pyracylene towards boat-shaped polycyclic scaffolds. The unique structural features of the resulting compounds were revealed by X-ray crystallographic analysis. Depending on the extent of π-expansion the compounds display intense bathochromically shifted absorption bands in their UV/Vis spectra and are prone to several redox events as documented by cyclic voltammetry. The experimental observations are in line with the computational studies based on density functional theory, suggesting progressive narrowing of the HOMO-LUMO gap and distinct evolution of the electronic structure and aromaticity.
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