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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Hidden silylium-type reactivity of a siloxane-based phosphonium-hydroborate ion pair
Nicolò Fontana1, Noel Angel Espinosa-Jalapa1, Michael Seidl1
1Institut für Anorganische Chemie, Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitätsstraße 31, Regensburg D-93053, Germany. jonathan.bauer@ur.de.
Abstract:
A new class of siloxane-based cations with hidden silylium-type reactivity is provided, which, in combination with an arylborate counteranion, initiates a highly selective para-C(sp2)-F defunctionalization of a perfluorinated aryl group. The hydrodefluorinated aryl borane is obtained as a crystalline solid via continuous sublimation during the reaction. The heterocyclic six-membered cation could be obtained single-crystalline after dehydrogenative anion exchange. DFT calculations give insight into the bonding within the siloxane-based cation and the mechanism of the ion pair reaction.
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