Homogeneous catalysts based on transition metals are of high industrial relevance. An important goal for this purpose is the light-induced start of the catalytic reaction. The electronic and steric influence of the olefin ligand upon the spectroscopic properties, stability and reactivity of bistriphenylphosphine-cinnamate and related complexes of group 10 were studied in this thesis. By means of these findings a direct prediction of the reactivity was possible based on the NMR-spectroscopic behaviour. Thus a specific design of photo-switchable complexes was possible, in which the olefin ligand could be cleaved from the metal via a selective light-induced intra-ligand cyclisation. This ring closure was examined with the ligand itself as well as in the complexes, concerning electronic and steric influences.