Mono-, di- and trinuclear complexes of bis(terpyridine) ligand: Synthesis, crystal structures and magnetic properties

Application of Stille-coupling protocol allowed for synthesis of new bis(terpyridine) ligand L (6′,6″-(2-phenylpyrimidine-4,6-diyl)bis(6-methyl-2,2′-bipyridine)) which comprises two tridentate N-donor subunits, designed so as to exploit the formation of supramolecular architectures of different nuclearity. Further complexation, while maintaining reaction parameters unaltered, with the following salts: CoCl2 (1), Co(NO3)2 (2), Cu(NO3)2 (3) and Mn(ClO4)2 (4) led to three different classes of compounds: mono-, di- and trinuclear species, the result of self-assembly being contingent on the choice of the metal ion as well as to its corresponding counterion. Single crystal structures of [Co(L)Cl2] (1), [Co2(L)(NO3)4](CH3CN)2 (2), [Cu2(L)(NO3)4](CH3CN)2 (3) and [Mn3(L)2(H2O)2(CH3CN)4](ClO4)6·2H2O (4) are presented, together with description of their magnetic behavior. Delusively simple coordination compounds were found to self-assemble into interesting supramolecular architectures in the solid state: 1D pillar-like constituent arranged in the helical manner (1), sheets of isostructural 2 and 3, hydrogen bonded zig-zag shaped chains (4). Magnetic susceptibility measurements made the determination of both antiferromagnetic interactions and metal ions′ multiplicity possible.

New complexes of bis(terpyridine) ligand L (6′,6″-(2-phenylpyrimidine-4,6-diyl)bis(6-methyl-2,2′-bipyridine) have been synthesized and characterized, what resulted in mononuclear [Co(L)Cl2] (1), dinuclear [Co2(L)(NO3)4](CH3CN)2 (2), [Cu2(L)(NO3)4](CH3CN)2 (3) and trinuclear [Mn3(L)2(H2O)2(CH3CN)4](ClO4)6·2H2O (4) species, the outcome being contingent on the choice of the metal ion and its corresponding salt.Figure optionsDownload as PowerPoint slide