Monodentate anionic

Many analogs of [Rh(NO)Cl2(PPh3)2] are known since other group V ligands may replace PPh3, and other monodentate anions the chloro ligands. However, the latter are not derivatives of [Rh(NO)Cl2(PPh3)2] since they have all been obtained from other sources. 

In general, given that symmetric bidentate, asymmetric bidentate, and even monodentate anion configurations are seen in the various lactoferrin structures, it seems likely that it is changes of this nature that are detected spectroscopically. 

Hou, Z.M. and Wakatsuki, Y. (2002) Lanthanide(ll)complexes bearing mixed linked and unlinked cyclopentakienyl-monodentate-anionic ligands. Journal of Organometallic Chemistry, 647, 61. 

Generally a monodentate anionic ligand like alkoxide, amide, halide (unless otherwise indicated)... 

Although it is obvious that anions do react in the same way as metal cations with water, the anions are treated merely as monoprotonated species that may either compete with the water (HX) or with the hydroxyl ions (monodentate anion X ) in the coordination sphere. The electronegativity can be... 

FIGURE 8.16 Electronegativity vs. pH diagram for the complexation of by monodentate anions as a function of the number of anions other than the hydroxyl in the coordination sphere. For example, the acidity range for complexation by chloride ions is determined by the x(Cl) and x(HCl) values. (From Jolivet, J.-R, Metal Oxide Chemistry and Synthesis, John Wiley Sons, Chichester, U.K., 2000, 206. With permission.)... 

In addition to the nickel complexes discussed above the interaction of complexes Cu° [H4](X )l1, Cu [H4](X )l2, Fe°I [H4](Me)Ll Y and Cr [H4](Me)Ll Y (Y = monodentate anion) with dioxygen in aerated acetone was also studied. It was found that these complexes are obviously not dehydrogenated, since the vis spectra were stable for long periods of time. 

Structural distortions and associated high lability often prevent kinetic data on substitution reactions of four-coordinate copper(II) compounds being obtained. Slightly distorted square-planar coordination is found for the copper complexes [CuXL] (L is AT-(2-(diethylamino)ethyl)salicylaldiminate, 6 X are monodentate anionic ligands or water), confirmed by X-ray analysis for X = NCS . The... 

Platinum co-ordination complexes share the common formula PtA2X2 with only the a s-isomers displaying an anti-tumour activity. The active X ligands are monodentate anions of intermediate leaving ability, whereas the amine A ligands influence... 

Compounds with Other Ligands The Ni(I)-Ni(I) bond can be bridged by a monodentate anionic/neutral ligand to form a diamond-shape NijXj core (X = monodentate anionic/neutral ligand) or a triangular Ni2X core (Scheme 10.20). 

The ascorbate complexes give highly water soluble species and were first synthesized with monodentate anionic ascorbate. The coordinated ligand is, however, very reactive and the complex rearranges in solution to a unique 0,C-bound chelate. Figure 3.4 [72]. The monodentate O-bound form is considered to be the most active form of the ligand but will not apparently persist in solution. Mechanistic studies on the formation of the C-bound species have been reported [121]. The nature of active species reported is therefore in some doubt [73], and the biological data are impossible to interpret since no correlation with the known chemistry was made. The observed chemistry does underline the need to examine carefully the stability of apparently active complexes and for full characterization of these complexes. All complexes should be characterized as fully as possible, which in many instances has not been the case. 

Reactions of Sm(Cp )2(THF)2 Sm(Cp )2 with organomercury reagents Reaction of Sm(Cp )2(THF)2 with monodentate anionic ligands Reactions of SmCp 2 and Sm(Cp )2-(THF)2 with alkenes, alkynes, and related unsaturated compounds... 

Aqueous cobalt(II) ions usually form tetrahedral complexes with monodentate anionic ligands such as Ch, SCN- and OH-. 

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