A new linear trinuclear cobalt complex bearing oximato and azido ligands: synthesis, structure, and magnetic characterization

The reaction of CoCl2 center dot 6H(2)O, mpkoH (methyl 2-pyridyl ketone oxime), NEt3, and NaN3 in a 1 : 1 : 2 : 1 molar ratio affords a linear trinuclear complex, [(Co2CoII)-Co-III(mpko)(4)(N-3)(4)(H2O)(2)] (1). Complex 1 has been characterized by single-crystal X-ray diffraction, elemental analysis, and infrared spectrum. Three cobalt ions are in the center of distorted octahedra, which are connected by two mu-1,1 azides and two oxime oxygen atoms to form a linear trinuclear structure. Discrete units of 1 are connected to form a stable 3-D supramolecular network by C-H center dot center dot center dot O and C-H center dot center dot center dot N weak interactions. Variable temperature magnetic susceptibility measurements reveal that 1 exhibits antiferromagnetic behavior.