Mixed ligand compounds

Some typical mixed ligand compounds are substituted carbonyl or halide compounds of the general formula  

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At low temperature, the emission spectra of the complexes are well-structured and assigned to ligand-localised nn phosphorescences , responsible for multiexponential luminescence decays observed with mixed-ligand compounds [125,126],... 

The simplest O-containing ligands are represented by water, alcohols, aldehydes, ketones, dioxane, organic acids, and their ethers. Dissolution of metal salts is used to prepare aqua complexes. Dissolving crystallohydrates of metal salts, aqua-containing coordination (in many cases, mixed-ligand) compounds are formed too. The examples of complexes of alcohols, acids, and dioxane are represented in a monograph [10, p. 95], They could be illustrated by reactions (3.15), (3.16), and (3.17), respectively ... 

Mixed ligand compounds containing a tetraphenylcyclobutadiene ring have been formed in low yield according to Eq. (5) (43). 

The reaction is reversible (equation 3, step a) and, furthermore, a mixture of stannate complexes may undergo disproportionation to establish an equilibrium between homo-and mixed-ligand compounds (equation 3, step b). Moreover, the aryloxy mixed ligand stannates 36-38 are more stable than a 1 1 mixture of the corresponding dichloro- and bis(aryloxy)-stannates. Thus, the stability of the TAS stannates with TBP structures is highly affected by the nature of the equatorial organic groups and apical heteroatom substituents. 

Reaction of the metal ethoxide [M(OEt)2(HOEt)4] with the desired /3-diketone has been used as an anhydrous method to Group 2 /3-diketonates and mixed ligand/3-diketonate-alkoxide compounds. Presumably, the liberated HOR has a lower binding ability compared to liberated H20. Drake et al. have prepared [Sr3(tmhd)6(Htmhd)] and [Ba4(tmhd)8] by the reaction of Eq. (19).177 Equation (20) gives the generalized reaction for formation of mixed ligand compounds of formula [M(X)n(OR)2 ]) .184185... 

The sulfate MnS04 and its hydrates (7, 5, 4, 2 and 1) represent the stable oxidation state under ambient conditions. Compounds are colourless in finely-divided form and pale pink or rose coloured when crystalline. All appear to be examples of high spin octahedral Mn11. Aqueous solutions have been much studied, to define the physical parameters, because of their importance in Mn production from its ores. Stability constants for 1 1, 1 2 and 1 3 species have been defined but detail (structurally) of the labile Mn polyhedra is unclear. Examples of unidentate and bridging sulfato are seen in the known crystal structures, but not bidentate or terdentate to the same metal atom. (However, bidentate function may occur in some of the mixed-ligand compounds described earlier.)... 

A recent report739 describes several mixed ligand compounds [Mn(R2dtc)2X2] (X = Cl, Br). 

Other examples of cyclic oligomers are the mixed-ligand compounds 8-16.49,50 These oligomers are best described as dimers of dimers forming squares and rectangles. Their syntheses stem from the dimeric materials [Cp MCl2]2 (M = Rh, Ir Cp = C5Me5) to which is... 

A few neutral mixed-ligands compounds were also reported. These are cis and fra/ 5-Tc(CO)3Cl(CNrBu)2 and Tc(NO)Br2(CNrBu)3. Two five-coordinate Tc(III) compounds Tc(CA//Eir)(L) where L is a tetradentate ligand containing some P and S atoms have been studied. More recently, three five-coordinate neutral compounds with the formula Tc(S3NC6Hi2)(CNR) where R=cyclohexyl, benzyl or CH2COOEt were also reported. 

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