Transition metal centres offer an obvious way for the introduction of charge centres or charge-carrying centres into new materials. The coordination of metal centres to ligands containing two or more distinct metal-binding domains provides a phenomenological and methodological approach to the assembly of designed novel materials. The limitations of this approach are currently being probed, and this chapter will provide an overview of the area. The emphasis will be upon synthesis rather than the properties of the materials and, in particular, the controlled assembly of materials of known nuclearity and topology.In order to keep this chapter to a reasonable length, the coverage will be restricted in a number of ways. Firstly, materials which are 'truly' polymeric will only be discussed if there are good solid state structural data to support their formulation and structural integrity. Secondly, the emphasis will be placed upon systems in which the ligand predisposes the assembly towards a particular structure. This latter restriction means that little will be said about halide. oxy and hydroxy bridged systems. Furthermore, it will be assumed for the most part that the ligands involved play some r61e in the electronic communication between metal centres and 'insulating' spacers will not be discussed in detail. In particular, the design of extended molecular materials will be discussed.The methods adopted involve the use of bridging ligands containing two or more metal-binding domains. A metal-binding domain is usually readily recognized as a conventional ligand type (for example, a phosphine, carboxylate, thiolate or oligopyridine). The linking together of the domains utilises conventional organic synthetic methods. In an ideal case, simply mixing the bridging ligand with an appropriate metal source, usually, but not necessarily in homogeneous solution, results in the formation of the desired oligomeric system. This process is shown in Fig. 1 [l].It is immediately apparent that a number of features need to be carefully controlled if the desired assembly process is to occur.The stability of the desired assembly must be maximised in order to drive the system towards the correct (i.e. wanted) product. The simplest way to achieve this is by the use of multidentate chelating ligands rather than monodentate donors. For this reason, systems based upon chloride, oxy or hydroxy bridges are not covered in detail in this article, because, although they possess extremely interesting properties, it is not usually possible, n priori, to predict exactly what material, morphology and topology will be obtained.The metal-binding domain can be tailored to the desired metal centre. This may be at a gross structural level by simply matching up the number of donor atoms to

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Im Rahmen erneuter Untersuchungen von Synthesewegen für sulfonierte 2,2′‐Bipyri‐ 136 dyl(bipy)‐Derivate wurden (II) und (V) (Gesamtausb.

ChemInform Abstract The Cu complex (I) and its Ni and Zn analogues are prepared from the title ligand and the metal acetates in boiling MeOH and isolated as PF6 salts (60-80% yield). Heating a MeOH solution of the ligand and (Cu(MeCN)4)PF6 in air to reflux gives (II) (60-70% yield). (I) crystallizes in P1 with Z=2, (II) in P21/c with Z=2. None of the copper complexes shows activity as a catalyst for the oxidation of phenol by O2.

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