Fiche publication
Date publication
juillet 2006
Auteurs
Membres identifiés du Cancéropôle Est :
Pr LEHN Jean-Marie
Tous les auteurs :
Barboiu M, Lehn JM
Résumé
We describe here a study of the coordination binding of Co2+, Cu2+ and Pb2+ ions to the ditopic ligand 1, leading to the formation of rack-type and double helical monomers. We report the crystal structures of three such complexes 5-7, which further self-organize into complementary duplex-rack, square and double helical architectures in the solid state. The ligand I discussed in this paper operates under conditions in which the two terpyridine (terpy) coordination sites resulted from Pyridine-Pyridine-Pyridazine connected sequences can be involved in the orthogonal binding events of the octahedral metal ions. In terms of molecular adaptability the formation of rack-type and double helical architectures represents the best coordination frameworks of the rigid ligand 1 presenting unfavorable orientation of coordination vectors. In terms of programmed self-assembly the formation of the different metallo-architectures 5, 6 and 7 underlines the fact that despite the role of the strength of the coordination interactions and of maximal site occupation, other factors like stacking, binding of anions (triflate or tetrafluoroborate anions stabilizing the network of metallic ions) and of solvent molecules may interfere and influence the nature of the favored output species.
Référence
Rev Roum Chim. 2006 Jul-aug;51(7-8):581-8.
