Synthesis of polypridyl complexes of ruthenium(II) containing three different bidentate ligands

A general synthetic method has been developed for the synthesis of heteroleptic tris(polypyridyl) complexes of ruthenium(II), [Ru(pp)(pp[prime])(pp[double prime])][sup 2+]. This method opens new avenues for the preparation of molecular assemblies and for the systematic variation of excited-state properties. For example, the results of a study on the ground- and excited-state properties of a series of these complexes reveal a strategy for the preparation of black chromophores which will absorb light strongly throughout the visible region of the spectrum.