Mixed donor chelate ligands

Thioether ligand complexes are not very common, however, studies since the mid 1990s have dramatically increased the number of structurally characterized examples. Almost all of these compounds are with chelate or macrocyclic ligands that will stabilize thioether coordination. Mixed donor multidentate ligands containing thioether donors will be discussed in Section 6.8.11. 

Mixed donor didentate ligands containing selenium are less well known than their sulfur analogues. A typical example of an Se,N donor is (41), which coordinates as a didentate chelate another is (42), a selective analytical reagent for platinum group metals. The monoanionic (43) forms neutral ML2 complexes (M = Zn, Cd, Hg) with an overall N2Sc2 donor set, with the imine N selected as a much better donor than the alternate ether However, Se,0 donor chelation is displayed by the butane-2,4-dionate analogue... 

Mixed O, N donor molecules are truly extensive and structurally diverse, and only a few selected examples will be presented. In line with other 2-substituted pyridine analogs reported in this chapter, it is worthwhile noting the chemistry of 2-pyridone (or 2-hydroxypyridine, Hopy), which can form O-bonded monodentate complexes such as Co(Hopy)4(N03)2, but as the monoanion is an effective chelate ligand, forming Co(opy)2 and Co(bpy)(opy)2 compounds.454 An unusual solid state melt reaction with Co(OAc)2 yields the dodecanuclear cluster Co12 (OH)6(OAc)6(opy )12.455... 

Organozinc Alkoxides Bearing Chelating Mixed Donor Ligands 375... 

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