Coordination chemistry especially of the transition metals is an important area of chemical research as it shows tremendous interdisciplinary relevance, e.g. for catalysis and for bioinorganic chemistry including even aspects of medicine regarding therapy as well as diagnosis. In this context, coordination chemistry studies under confined conditions seem to be of special importance. One unique class of the coordination chemistry is presented by the polyoxometalates which can be considered as soluble metal-oxide fragments with an enormous structural variety and a multitude of interesting properties. The present thesis is dealing with self-assembly processes of polyoxomolybdates but also with performing well-defined reactions at well-defined sites of the structurally well-defined but very complex metal oxide-based nanoobjects.