Bridging ligands synthesis

Stang and coworkers also reported the synthesis of platinum-acetylide dendrimers using 1,3,5-triethynylbenzene as the bridging ligand [27]. Their strategy was very similar to the above, and they prepared dendrimers up to the second generation. 

Barnard, P.J., Baker, M.V., Bemers-Price, S.J., Skelton, B.W. and White, A.H. (2004) Dinudear gold(I) complexes of bridging bidentate carbene ligands Synthesis, structure and spectroscopic characterisation. Dolton Transactions, 1038-1047. 

Synthesis of the Bridging Ligand 2,2 ,3,3 -tetra-2-pyridyl-6,6 -biquinoxaline, tpbq... 

The synthesis and properties of [ Os(bpy)2 3(/r-181)] have been reported the formal oxidation state of the Os centers is +3. In contrast, [ Ru py)2 3(/i-181)] + contains Ru° with the bridging ligand possessing three semiquinone domains. The complex undergoes three reversible ligand-centered oxidations taking it ultimately to [ Ru(bpy)2 3(/i-181)]°" with (181) in a tris(quinone) form. The wavelength of the intense NIR absorption (MLCT) that the complex exhibits varies with oxidation state. " ... 

The synthesis of [RuL] where H2L = 2,3-naphthalocyanine has been reported. Reactions with suitable bridging ligands lead to oligomers, electrical conductivity data for which have been compared with those of related compounds. The tetrakis(tert-butyl) derivative [Ru ( BU4L)] has been prepared by the thermal decomposition of the [Ru( Bu4L)(Lax)2] (Lax = NH3, 3-Clpy). ... 

In the past few years we have concentrated our efforts on the N-N bischelating bridging ligands 2,3- and 2,5-bis(2-pyridyl)pyrazine (2,3- and 2,5-dpp), respectively (Figure 1). As we will see later, for the synthesis of dendrimers we have mainly used 2,3-dpp since one of its two chelating sites can be protected by methylation. The methylated form of 2,3-dpp, 2,3-Medpp+, is also shown in Figure 1. 

Recently the divergent iterative approach, welt known in oiganic synthesis, has been successfully extended to prepare polynuclear dendrimer-type complexes containing up to 22 metal centers using 2,3-dpp as bridging ligand. The two... 

Rasmussen, S.C., Richter, M.M., Yi, E., Place, H. and Brewer, KJ. (1990) Synthesis and characterization of a series of novel rhodium and iridium complexes containing polypyridyl bridging ligands Potential uses in the development of multimetal catalysts for carbon dioxide reduction. Inorg. Chem., 29, 3926—3932. 

Figure 4.6 Synthesis of chiral molecular squares 6a-d based on enantiopure linear l,l -binaphthyl-derived bipyridyl bridging ligands and /ac-Re CO)3CI corners.

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