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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Halogen Bonding Helicates Encompassing Iodonium Cations
Alan Vanderkooy1, Arvind Kumar Gupta2, Tamás Földes3,4
1Department of Chemistry-BMC, Uppsala Universitet, Husargatan 3, 752 37, Uppsala, Sweden.
Abstract:
The first halonium-ion-based helices were designed and synthesized using oligo-aryl/pyridylene-ethynylene backbones that fold around reactive iodonium ions. Halogen bonding interactions stabilize the iodonium ions within the helices. Remarkably, the distance between two iodonium ions within a helix is shorter than the sum of their van der Waals radii. The helical conformations were characterized by X-ray crystallography in the solid state, by NMR spectroscopy in solution and corroborated by DFT calculations. The helical complexes possess potential synthetic utility, as demonstrated by their ability to induce iodocyclization of 4-penten-1-ol.
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