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Updated: Nov 8, 2025

Interactive Molecular Model Assembly with 3D Printing
Published on: August 13, 2020
Carbo-mer of Barrelene: A Rigid 3D-Carbon-Expanded Molecular Barrel
Chongwei Zhu1, Albert Poater2, Carine Duhayon1
1LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France.
Abstract:
After extensive studies of 1D and 2D skeletal carbo-mers based on C8 π-conjugating dialkynylbutatriene units (DABs: ∼C≡C-(R)C=C=C=C(R)-C≡C∼) bridging sp or sp2 centers in carbo-butene, carbo-xylylene or carbo-benzene derivatives, 3D versions are envisaged through carbo-barrelenes and partially reduced derivatives thereof where two or three DAB blades span a bridge between sp3 carbinol vertices or ether thereof. For R=Ph, stable representatives were synthesized through a pivotal [6]pericyclynedione, and extensively characterized by spectroscopic, electrochemical and crystallographic methods. Density functional theory calculations allow detailed analysis of structural and electronic features of the 7 Å high C26 barrel-shaped molecules, and show that they can behave as cages for ionic species. Beyond aesthetical concerns, the results could open prospects of applications in host-guest supramolecular chemistry and single molecule charge transport.
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