Tetrametallic complexes

Tetrametallic complexes of type Pt2Mo2Cp2(CO)6(PEt3)2 can also be prepared. The complex has a triangulated parallelogram core structures (152).1463... 

Three complexes of K+ with monoanionic C[4] and tBuC[4] in the cone conformation have been described with either O- and 7t-bonding or O-bonding alone,26 whereas strong Tt-bonding of K+ has been evidenced in the tetrametallic complex of four-fold deprotonated tBuC[4].27 The comparison of K+, Rb+, and Cs+ complexes of monoanionic C[4] and tBuC[4] is particularly interesting, as Cs+ is always complexed in an endo fashion, whereas Rb+ and K+ can be either exo- or endo-coordinated.28... 

Fig. 91. Tetrametallic complex exhibiting Rn -to-Ln (Ln = Nd, Yb) directional energy transfer (Guo et al., 2004).

Similarly, from a mixed germyl(stannyl)mercury compound, the tetrametallic complex (CgF5)3SnHgM(PPh3)2Ge(C6F5)3 was obtained as a mixture of cis and trans isomers345. 

C,gH220,o, Tetraethyl 2.3-dioxobutane-1,1,4,4-tetracarboxylate, tetrametalate complexes, 29 275... 

In a kind of inversion of this concept, hydrocarbons can also serve as platforms for polycluster systems the tri- and tetrametallic complexes shown in Chart 8 (A and B) were recently prepared in our laboratory and characterized via X-ray crystallography at the University of Heidelberg (59). Compounds of this type are prototypes for extended oligomeric and polymeric networks such as that proposed in Chart 8(C), that are expected to exhibit extensive electron-delocalization between the metal centers (60). Systems of this kind, together with alkynyl-and phenyl-linked polyhedra, and multidecker sandwich-based arrays, are current targets of our research (61). 

An elegant approach to a novel Fe-Ru-Re-Rh tetrametallic complex, based on the 1,3-diethynyl-5-diphenylphosphino benzene core, is given by using a consecutive reaction methodology as presented in Scheme 10 including, dehydrohalogenation and carbon-carbon coupling reactions [64],... 

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