Mixed ligand system

Hahde ligands are found in homoleptic complexes as well as in mixed ligands systems. HaUde complexes of Ir(IV) such as [IrCy [16918-91-5] are readily reduced to Ir(III) species, eg [IrCy [14648-50-1], in neutral or basic solution, or in the presence of reducing agents such as KI, oxalate, or photochemical activation (173). 

Chiral MOFs have to cope with two kinds of challenges when they are used as catalysts. First, in those cases where chirality is induced via sp carbon centers, the incorporation of such centers may confer a degree of flexibility to the framework that eventually impairs the stability after desolvation. Such problems can be circumvented, for instance, using mixed ligand systems where a rigid nonchiral backbone ensures the stability of the structure [82], MOFs with large and flexible chiral ligands... 

When N-acetylcysteine and thiomalate were studied in a mixed ligand system, the respective activation entropies were found to be AS = —141 and —151J mol ... 

The LFMM parameterization was based only on the homoleptic systems but was able to reproduce DFT for all the mixed-ligand systems. The spin state changes from high to low already for [CoF5(CN)]3. However, the interelectron repulsion was an additive correction and could not play a role in determining the structures. 

Although the foregoing reactions are quite facile, they are not competitive with the very well-established conventional methods for synthesis of metallocenes. Cyclopentadiene, nevertheless, can be a useful substrate in metal atom synthesis as part of a mixed-ligand system (6, 110, 136, 140), e.g.,... 

Gamble, D.S. and Langford, C.H. (1988) Complexing equilibria in mixed ligand systems tests of theory with computer simulations. Environ. Sci. Technol, 22, 1325-1336. 

Fig. 16 Structures of the redox catalyst tris(l,10-phenanthroline-5,6-dione) ruthenium(II) perchlorate 1 and the mixed ligand system consisting of l,10-phenanthroline-5,6-dione and one N,N, A-tris(aminoethyl)amine ligand 2...

Other mixed ligand systems studied include the troponeiminates (43) and 8-hydroxyquinoline in both cases [MnL2L ] and [MnLL2] have been characterized. [Mn(acac)(salen)] represents a non-planar form of the salen ligand, related to the well-characterized Co111 compounds.610... 

Other Mixed-Ligand Systems. From the smaller number of sulfato-fluorometalates, two recent examples are given. 

For many AD reactions, the bisalkaloid systems (cf. Figure 3.1), in particular the (DHQ)2PHAL and (DHQD)2PHAL systems, provide good asymmetric induction. Studies with mixed ligand systems showed that the (DHQD)2PHAL complex was... 

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