Anionic structure ligands

Cinellu, M.A., Minghetti, G., Pirma, M.V., Stoccoro, S., Zucca, A. and Manassero, M. (2000) Gold(lll) derivatives with anionic oxygen ligands mononuclear hydroxo, alkoxo and acetato complexes. Crystal structure of [Au(bpy)(OMe)2][Pp6]. Journal of the Chemical Society, Dalton Transactions, (8), 1261. 

In case of [M(edt)2] based salts, the size of the small anion is similar to the size of the CsMes ligand of the cation and only type I structural motives (D+ A D+ A-chains) were observed. For the intermediate size anionic complexes, [M(tdx)2], [M(mnt)2] and [Ni(a-tpdt)2], the most common structural motive obtained in salts based on those anions is also of type I. For the larger anionic complexes, [M(bdx)2] and [M(dmix)2], types III and IV chain arrangements were observed. In both cases anion molecules (type IV) or face-to-face pair of anions (type III) alternate with side-by-side pairs of cations. The complexes [M(mnt)2] and [M(dmix)2] (M = Ni, Pd and Pt) frequently present dimerization in the solid state [19], and they are the only anions where the chain arrangements present face-to-face pairs of anions (structural motives II and III). The variety of structural... 

The role of electronic structure in Mn and Co site preference and mobility can to some extent be understood through ligand-field theory (LFT). LET qualitatively explains how the degeneracy of the 3d orbitals is broken when a free TM ion is surrounded by coordinating anions. The ligand-field splitting of d orbitals in octahedral and tetrahedral coordination is pictured in Figure 6. ... 

Since these intermediates were characterized (10) as monomeric PBP complexes of Fe(III) with a dianionic acyclic pentadentate ligand, it was the intention to isolate and structurally characterize some of them, since no examples of such structures have been reported in the literature. With this aim, the [Fe(dapsox)(H20)2]C104 complex 12 was synthesized, which is analogous to the intermediate [Fe(dapsox)Cl(H20)]. The results of an X-ray structural analysis (Fig. 6) confirmed the PBP structure of the complex and double deprotonation of the ligand. This structure is the first example of a monomeric structure of Fe(III) with an anionic pentadentate ligand and confirms previously suggested hydrolytic processes (10) which led to the production of complex 10. 

Analogous to the work on dipicolinic acid reported in Section 31.5.2, a range of titanium(IV) peroxo complexes (35) have been prepared which encompass an oxygen-nitrogen anionic chelating ligand and hexamethylphosphortriamide.171 The crystal structure of... 

Substituted dithioformate anions as ligands R C(S)S are usually called dithiocarbamates (R = R2N), alkyl and aryl dithiocarbonates or xanthates (R = RO), alkyl and aryl trithiocar-bonates or thioxanthates (R = RS). Dithioacid anions (R = alkyl, aryl) have been rarely used as ligands of nickel(II) because of their instability. Structural properties of selected nickel(II) complexes with substituted dithioformate, dithiolene and related ligands are shown in Table 90. 

In order to introduce more flexibility into the structure of dinuclear copper(II) complexes, bridging ligands of type Y, such as p-XYLpy2 (261),595 have been combined with simple anion bridging ligands, such as Cl-, OH-, (CN)-, (OPh)- and (N3)-, to produce very asymmetric... 

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