887511-93-5Relevant articles and documents
Preparation and characterization of CrIII, MnII, FeII, CoII and NiII complexes of a hexaazadithiophenolate macrocycle
Journaux, Yves,Glaser, Thorsten,Steinfeld, Gunther,Lozan, Vasile,Kersting, Berthold
, p. 1738 - 1748 (2006)
The ligating properties of the 24-membered macrocyclic dinucleating hexaazadithiophenolate ligand (LMe)2- towards the transition metal ions CrII, MnII, FeII, Co II, NiII and ZnII have been examined. It is demonstrated that this ligand forms an isostructural series of bioctahedral [(LMe)MII2(OAc)]+ complexes with MnII (2), FeII (3), CoII (4), NiII (5) and ZnII (6). The reaction of (LMe)2- with two equivalents of CrCl2 and NaOAc followed by air-oxidation produced the complex [(LMe)CrIIIH2(OAc)]2+ (1), which is the first example for a mononuclear complex of (L Me)2-. Complexes 2-6 contain a central N3M II(μ-SR)2(μ-OAc)MIIN3 core with an exogenous acetate bridge. The CrIII ion in 1 is bonded to three N and two S atoms of (LMe)2- and an O atom of a monodentate acetate coligand. In 2-6 there is a consistent decrease in the deviations of the bond angles from the ideal octahedral values such that the coordination polyhedra in the dinickel complex 5 are more regular than in the dimanganese compound 2. The temperature dependent magnetic susceptibility measurements reveal the magnetic exchange interactions in the [(L Me)MII2(OAc)]+ cations to be relatively weak. Intramolecular antiferromagnetic exchange interactions are present in the MnII2, FeII2 and CoII2 complexes where J = -5.1, -10.6 and ～-2.0 cm-1 (H = -2JS1S2). In contrast, in the dinickel complex 5 a ferromagnetic exchange interaction is present with J = +6.4 cm-1. An explanation for this difference is qualitatively discussed in terms of the bonding differences. The Royal Society of Chemistry 2006.
