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Updated: Jul 28, 2025

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Brominated [20]silafulleranes: pushing the limits of steric loading
Marcel Bamberg1, Thomas Gasevic2, Michael Bolte1
1Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany. matthias.wagner@chemie.uni-frankfurt.de.
Abstract:
Starting from the perhydrogenated silafullerane [nBu4N][Cl@Si20(SiH3)12H8], treatment with BBr3 leads to partially and exhaustively brominated clusters, [nBu4N][Cl@Si20(SiBr2H)12Br8] (120 eq. BBr3, room temperature, 30 min) and [nBu4N][Cl@Si20(SiBr3)12Br8] (300 eq. BBr3, 130 °C, 3 d). Perbromination is accompanied by a massively increased steric strain on the cluster surface, which explains why our approach achieves regioselective derivatization of the Si32 framework when mild conditions are maintained. Partial Br/H exchange on [nBu4N][Cl@Si20(SiBr2H)12Br8] (30 eq. iBu2AlH, room temperature, 16 h) affords [nBu4N][Cl@Si20(SiH3)12Br8].
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