title: Organometallic Probe for the Electronics of Base-Stabilized Group 11 Metal Cations.
abstract: A number of trimetalloborides have been synthesized through the reactions of base-stabilized coinage metal chlorides with a dimanganaborylene lithium salt in the hope of using this organometallic platform to compare and evaluate the electronics of these popular coinage metal fragments. The adducts of Cu(I), Ag(I), and Au(I) ions, stabilized by tricyclohexylphosphine (PCy3), N-1,3-bis(4-methylphenyl)imidazol-2-ylidene (ITol), or 1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidin-2-ylidene (CAAC), with [{Cp(CO)2Mn}2B](-) were studied spectroscopically, structurally, and computationally. The geometries of the adducts fall into two classes, one symmetric and one asymmetric, each relying on the combined characteristics of both the metal and ligand. The energetic factors proposed as the causes of the structural differences were investigated by ETS-NOCV (extended transition state-natural orbitals for chemical valence) analysis, which showed the final geometry to be controlled by the competition between the tendency of the coinage metal to adopt a higher or lower coordination number and the willingness of the cationic fragment to participate in back-bonding interactions.
authors.affiliation: Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.chemie.uni-wuerzburg.de/Braunschweig/index.html. h.braunschweig@mail.uni-wuerzburg.de.
authors.forename: Holger
authors.initials: H
authors.lastname: Braunschweig
authors.affiliation: Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.chemie.uni-wuerzburg.de/Braunschweig/index.html.
authors.forename: William C
authors.initials: WC
authors.lastname: Ewing
authors.affiliation: Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.chemie.uni-wuerzburg.de/Braunschweig/index.html.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kramer
authors.affiliation: Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, Sussex (UK).
authors.forename: James D
authors.initials: JD
authors.lastname: Mattock
authors.affiliation: Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, Sussex (UK).
authors.forename: Alfredo
authors.initials: A
authors.lastname: Vargas
authors.affiliation: Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.chemie.uni-wuerzburg.de/Braunschweig/index.html.
authors.forename: Christine
authors.initials: C
authors.lastname: Werner
keywords: boron; carbenes; coinage metals; manganese; metal-metal interactions; structure elucidation