In the course of this thesis, two chemically very different topics are going to be discussed. The first part will cover the chemistry of borophosphonate and borophosphate cages, with regard to their application as building blocks for network structures or dendritic molecules. In the second part, the application of imidazolin- and imidazolidin-2-imines as ligands for the complexation of ruthenium and rhodium are going to be in the focus of the discussion. Borophosphonates and borophosphates represent a so far neglected compound class in the field of supramolecular chemistry. The synthesis of molecular well defined borophoshonates, as well as their incorporation into extended three-dimensional structures by the aid of supramolecular strategies, will be described. Borophosphonates show dynamic behavior on the molecular level, which was investigated by kinetic NMR experiments. Attempts to generate other derivatives, based on arsenic or thiophosphonic acids, will be presented as well. Furthermore, we will demonstrate the synthesis and isolation of borophosphate cages. In the second part, we are going to discuss the synthesis of chloro-bridged half-sandwich complexes that have been prepared by a newly developed protocol, which uses microwave heating. These compounds were used to synthesise new ruthenium and rhodium complexes based on imidazolin- and imidazolidin-2-imines, which show interesting behavior in solution and can be transformed by UV light or the addition of strong bases.