Trinuclear and mononuclear nickel(II) complexes incorporating tridentate 2-[(pyridine-2-ylimine)methyl]phenol ligand: Syntheses, crystal structures and magnetic properties

[Ni-3(Pymp)(4)(pya)(2)](NO3)(2)(CH3OH)(2) (1). [Ni-3(Pymp)(4)(pya)(2)]Cl-2(CH3OH)(2) (2) and [Ni(Pymp)(2)(Py)(2)] (3) (Hpymp = 2-1(pyridine-2-ylimine)methyl]phenol, pya = pyridin-2-amine and py = pyridine) were synthesized and characterized. Crystal structures reveal that I and 2 contain phenoxo-bridged and N-C-N bridged linear trinuclear cores (uncommon for trinuclear nickel complexes), with the central Ni(II) being coordinated in a NiO4N2 fashion while the two terminal Ni(II) atoms adopt a NiO2N4 coordination mode. Two novel coordination modes of Hpymp ligand are presented in 1 and 2. Complex 3 displays a NiO2N4 coordination mode with the Ni(II) in a slightly distorted octahedral environment. Magnetic measurements of 1 indicated that the Ni centers are ferromagnetically coupled. (c) 2008 Elsevier B.V. All rights reserved.