Polypyridyl coordination polymers

Impressive results in terms of the synthesis and characterization of soluble linear Ru-polypyridyl coordination polymers were reported in 1997 [10]. Reaction of tetrapyridylphenazine (tppz) with impure ruthenium precnirsors [Ru(R2bpy)Q3]x was found to give fairly low molecular weight polymers 7.3 with M 16,000 (DPn 15) (Eq. 7.2). However, when stoichiometric balance was possible due to... 

The generation of dendrimeric coordination polymers has also been an area of significant activity. Imaginative routes to novel Ru- or Pt-polypyridyl systems (eg, 65) (197) have been reported and many other ligand systems have been exploited (117,118,198-201). These materials are of interest with respect to their photophysical and electrochemical properties and possibly their catalytic behavior. 

Many PSPs are composed of probe dyes, such as polycyclic aromatic hydrocarbons (e.g., pyrene) and coordination compounds (e.g., platinum por-phryins and ruthenium(II) polypyridyl complexes) immobilized in various gas permeable polymer films such as silicon polymer, organic glassy polymers (e.g., poly(methylmethacrylate), polystyrene), fluorinated polymers, or cellulose derivatives such as ethyl cellulose [9,10]. As probe molecules interact with polymer matrices directly, the properties of PSPs strongly depend on the properties of polymer matrices. The oxygen permeability of polymer matrix is an especially important factor for highly sensitive PSP. 

The coordination compounds are widely used as luminescent probes for polymer-based PSP. The coordination compounds are classified into two categories. One is the transition metal polypyridyl complex. In this group, transition metals are Ru2+, Os+ and Ir3+ as shown in Fig. 10. The second group comprises the metalloporphyrins as shown in Fig. 11. Pt2+ and Pd2+ porphyrins are especially used as PSP probes. 

One of the more important aspects of complexes of the type cw-[Os(bipy)2(L2)] + (L = vinylpyridine) is then-use as derivatives to form electroactive polymer films. Thus polypyridine films containing redox-active Os centers can be generated by electropolymerization of the coordinated vinylpyridine ligands of the parent complex from homogeneous solution. Importantly, these polypyridyl films contain redox-active Os fragments at each unit. 

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