Abstract EN:

Catenanes, topologically non trivial molecules used to represent mostly synthetic challenges. Whereas the preparation of catenanes synthesised by forming stable covalent bonds in the last ring-forming step is much documented, the formation of such compounds using non-covalent bonds is much less common. The work presented in this thesis consists in the synthesis of [2]catenanes assembled via coordination bonds. Several bis-porphyrins and bis-pyridines were synthesized. Various metallic cations were inserted into the porphyrins: zinc (II), ruthenium (II) and rhodium (III). Catenanes were formed in two steps, from a bis-porphyrin and a dipyridyl unit, by using Cu(I)-N bonds to assemble acyclic complexes and interactions between pyridines and the metal complexed by the porphyrin to generate rings. Different aspects influencing on the stability of these non trivial molecules were studied. The choice of the metal inserted in the porphyrin determines the strength of the interaction. Moreover it determines if the formation of the assembly is either under thermodynamic or kinetic control. If the ring’s formation is under thermodynamic control, the geometrical complementarity between the ligands influences on the thermodynamic stability of the molecular structure. Better the geometrical fit, higher the association constant. Some rings, assembled via inerte coordination bonds are interesting precursors for the synthesis of asymmetric [2]catenanes or [2]polycatenanes.