title: Bismuth Undecahydro-closo-dodecaborane: A Retainable Intermediate of B-H Bond Activation by Bismuth(III) Cations.
abstract: The [B12 H12](2-) anion shows an extensive substitutional chemistry based on its three-dimensional aromaticity. The replacement of functional groups can be attained by electrophilically induced substitution caused by Brønsted or Lewis acidic electrophiles (e.g. Pt(2+)). Until now, it was impossible to structurally characterize a metal-substituted [B12 H12](2-) cage. When an aqueous solution containing both Bi(3+) cations and [B12 H12](2-) anions was heated, the charge-neutral bismuth undecahydro-closo-dodecaborane BiB12 H11 was obtained, representing a new class of metalated [B12 H12](2-) clusters. The title compound was characterized by single-crystal X-ray diffraction and NMR spectroscopic methods. Compared to the typical B-H bond, the short B-Bi single bond (230 pm) exhibits inverted polarity.
authors.affiliation: Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Lucas W
authors.initials: LW
authors.lastname: Zimmermann
authors.affiliation: Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Nguyen-Duc
authors.initials: ND
authors.lastname: Van
authors.affiliation: Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Dietrich
authors.initials: D
authors.lastname: Gudat
authors.affiliation: Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany. schleid@iac.uni-stuttgart.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schleid
keywords: B−H activation; bismuth; boranes; borates; umpolung