Syntheses, crystal structures and magnetic properties of three new binuclear Ni(II) complexes derived from tripodal tetradentate (N-4) ligands

Three new binuclear Ni(II) complexes [{Ni(L(22py))Cl}(2)](ClO(4))(2) (1), [{Ni(L(23py))Cl}(2)](ClO(4))(2) (2), and [{Ni(L(33py))Cl}(2)](ClO(4))(2) (3), {L(22py) = N-(2-pyridylmethyl)-N-(2-aminoethyl)-1,2-diaminoethane, L(23py) = N-(2-pyridylmethyl)-N-(2-aminoethyl)-1,3-diaminopropane, L(33py) = N-(2-pyridylmethyl)-N-(3-aminopropyl)-1,3-diaminopropane) have been synthesized. Single crystal X-ray structure analysis showed that in each complex two distorted octahedral Ni(II) ions are bridged asymmetrically by a pair of chloride anions. Variable temperature magnetic susceptibility measurements of 1 and 3 revealed dominant ferromagnetic exchange interactions.