Structure and magnetic characterization of some bicompartmental [N6O2] divalent metal(II) complexes using bis(phenolato) ligands bearing two pendant bis(pyridyl) amine arms

Reactions of the bicompartmental bis(phenolato) compound 6,6'-methylenebis(2-((bis(pyridin-2-ylmethyl)amino)methyl)-4-chlorophenol)hemihydrate (H2L 1/2 H2O) with 3d metal(II) ions afforded novel fully structurally characterized bridged acetato dinuclear complexes [Mn-2(HL)(mu(1,2)-OAc)(2)]PF6 (1) [Zn-2(HL)(mu(1,2)-OAc)(H2O)(0.75)-(MeOH)(0.25)](PF6)(2)center dot 0.45(H2O) (5) and [Cd-2(HL)(mu(1,1,2)-OAc)(OAc)(H2O)]PF6 center dot H2O (6) as well as the polymeric bridged-azido tetranuclear catena-[Cu-4(HL)(2)(mu(1,1)-N-3)(2)(mu(1,3)-N-3)(2)](NO3)(2 center dot)5H(2)O (4). The complex [Cu-4(HL)(2)(ClO4)(3)(H2O)(5)](ClO4)(3)center dot 5H(2)O (2) was partially characterized. In addition, three more dinuclear complexes [Cu-2(H2L)(NO3)(2)(H2O)(2)](NO3)(2) (3), [Cu-2(HL)(OAc)(CH3OH)](PF6)(2) (7) and [Cu-2(HL)(NCS)(2)]NO3 center dot 2H(2)O (8) were also isolated. All complexes were characterized by CHN elemental analysis, IR and UV-Vis spectroscopy, ESI-MS, conductivity measurements and X-ray single crystal crystallography for compounds 1, 4, 5 and 6, where the bis(phenolato) ligand displayed different deprotonation (H2L, HL- and L2-). The magnetic susceptibility measurements over the temperature range 2-300 K revealed very weak antiferromagnetic coupling in dimanganese(II) 1 (J = -1.64(1) cm(-1)) and almost negligible magnetic interaction in dicopper(II) 2 (J = 0(3) cm(-1)). In the azido catena[Cu-4(HL)(2)(mu(1,1)-N-3)(2)(m(1,3)-N-3)(2)](NO3)(2 center dot)5H(2)O (4) complex, the J value of -133(3) cm(-1) was obtained upon moderate-to-strong antiferromagnetic coupling through the di-mu(1,3)-N-3-bridged dicopper(II) unit with no magnetic interaction between the two copper(II) ions in the di-mu(1,1)-N-3-bridged unit.