Platinum n Polypyridine Systems

Besides the platinum and palladium diphosphine systems, platinum polypyridine complexes have also attracted attention in recent years [130-162). Their changes in spectroscopic and luminescence properties brought about by Pt Pt and n-n interactions are of particular interest [138-142). For instance, the square planar platinum(ii) diimine complex [Pt(bpy)Cl2) exhibits polymorphic behavior and rich photophysical properties [142-144). These, together with the recent growing development of platinum alkynyl systems [98, 122, 125, 145-147), mainly due to the 

Apart from the platinum(ii) diimine system, analogous platinum(ii) systems with planar tridentate ligands are also hot topics in current chemical research. Their useful physical and biological properties, such as interaction with DNA and proteins, were first reported by Lippard and coworkers [150, 151]. Subsequent reports by Che and coworkers described the luminescence properties of a series of platinum(ii) complexes with terpyridine ligands, [Pt(trpy)X] (X = Cl, Br, I, N3, 

n = 1 X = NH3, n = 2) [152]. McMillin and coworkers recently reported the photophysical properties of a series of platinum] n) terpyridyl complexes with different counter ions [153]. These classes of platinum]n) complexes have also been found to exhibit rich polymorphic properties and have been studied by Gray and coworkers [154]. 

The use of this synthetic route was analogous to that for the preparation of 

The monoynyl complex was found to emit at a longer wavelength compared to that of the diynyl complex (Table 10.3), which is similar to the trend observed in 

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