Nitridotechnetium(V) Complexes with N-Heterocyclic Carbenes and Unexpected (OSiMe<sub>2</sub>OSiMe<sub>2</sub>O)<sup>2</sup><sup>-</sup> Coligands
作者:Henrik Braband、Ulrich Abram
DOI:10.1021/om050245q
日期:2005.7.1
Reactions of [TcNCl2(PPhR2)3] complexes (R = Me, Et) with 1,3-diethyl-4,5-dimethylimidazol-2-ylidene yield air-stable nitridotechnetium(V) complexes with N-heterocyclic carbenes with up to four of these bulky ligands and, depending on the reaction conditions applied, 1,1,3,3-tetramethyldisiloxane-1,3-diolato coligands which were abstracted from silicon-based grease.
Gemischtligandkomplexe des Technetiums. XVI. Darstellung und Struktur von (1,2-Dicyanoethen-1,2-dithiolato)bis(dimethylphenylphosphan)nitridotechnetium (V), [TcN(Me2PhP)2(mnt)]
作者:S. Ritter、U. Abram、J. R. Dilworth
DOI:10.1002/zaac.19966221127
日期:1996.11
Abstract[TcN(Me2PhP)2(mnt)] entsteht bei der Reaktion von [TcNCl2(Me2PhP)3] mit dem Natriumsalz des 1,2‐Dicyanoethen‐1,2‐dithiolats (Na2mnt), wenn ein äquivalent des Liganden eingesetzt wird. Bei Verwendung eines Na2mnt‐überschusses und Reaktionszeiten von mehreren Stunden bildet sich das Komplexanion [TcN(mnt)2]2−, das in Form seiner Tetraalkylammonium‐ bzw. Tetraphenylarsoniumsalze isoliert werden kann.[TcN(Me2PhP)2(mnt)] kristallisiert triklin (Raumgruppe P1; a = 10,000(5); b = 14,182(6); c = 17,77(1) Å; α = 98,77(3); β = 103,77(3); γ = 104,55(3)°; Z = 4). Das Koordinationspolyeder ist eine quadratische Pyramide, in der das Metall um 0,56 Å über der durch die Schwefel‐ und Phosphoratome gebildeten Grundfläche angeordnet ist.
[Tc(NBCl2Ph)Cl2(Me2PhP)3] und [Tc(NBH3)Cl2(Me2PhP)3] - die ersten Technetium-Komplexe mit Nitridobrücken zwischen Technetium und Bor
[TcNCl2(Me2PhP)(3)] reacts with BCl2Ph or BH3 THF at low temperatures under formation of complexes containing a nitrido bridge between technetium and boron. The compounds are instable and decompose at room temperature under cleavage of the N-B bonds.The pale-purple [Tc(NBCl2Ph)Cl-2(Me2PhP)(3)] crystallizes in the orthorhombic space group Fdd2. The Tc=N bond is only slightly lengthened by the formation of the N-B bond of 1.564(4) Angstrom. However, a considerable lengthening of the Tc-Cl bond in trans position to the nitrido ligand is observed which can be attributed to an decreasing of the structural trans influence of the nitrido moiety. A similar structural feature can be found in [Tc(NBH3)Cl-2(Me2PhP)(3)] which is the first structurally characterized transition metal complex containing a nitrido bridge to unsubstituted borane.
The title compound, [TcCl2(C4H10O2PS2)(C8H11P)(2)], is formed during the reaction of [TcNCl2(Me(2)PhP)(3)] with excess sodium diethyldithiophosphate involving cleavage of the technetium-nitrido bond. The Cl ligands are trans with respect to each other, with a mean TcCl distance of 2.3545 (6) Angstrom. The diethyldithiophosphate is bonded as a chelate ligand with Tc-S bond lengths of 2.4639(7) and 2.4787(6) Angstrom.