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Updated: Jun 29, 2025

Determination of Thermodynamic Properties of Alkaline Earth-liquid Metal Alloys Using the Electromotive Force Technique
Published on: November 3, 2017
From alkaline earth to coinage metal carboranyls
Kyle G Pearce1, Louis J Morris1, Thomas P Robinson1
1Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK. a.l.johnson@bath.ac.uk.
Abstract:
The β-diketiminato calcium and magnesium complexes, [(BDI)MgBu] and [(BDI)CaH]2 (BDI = HC{C(Me)NDipp}2; Dipp = 2,6-di-isopropylphenyl), react with ortho-carborane (o-C2B10H12) to provide the respective [(BDI)Ae(o-C2B10H11)] (Ae = Mg or Ca) complexes. While the lighter group 2 species is a monomer with magnesium in a distorted trigonal planar environment, the heavier analogue displays a puckered geometry at calcium in the solid state due to Ca⋯H-B intermolecular interactions. These secondary contacts are, however, readily disrupted upon addition of THF to provide the 4-coordinate monomer, [(BDI)Ca(THF)(o-C2B10H11)]. [(BDI)Mg(o-C2B10H11)] was reacted with [NHCIPrMCl] (NHCIPr = 1,3-bis(isopropyl)imidazol-2-ylidene; M = Cu, Ag, Au) to provide [NHCIPrM(o-C2B10H11)], rare C-bonded examples of coinage metal derivatives of unsubstituted (o-C2B10H11)- and confirming the alkaline earth compounds as viable reagents for the transmetalation of the carboranyl anion.
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