The First Azide(μ_1,1)-Bridged Binuclear Cobalt(II)−Imino Nitroxide Complex with Ferromagnetic Behavior

Abstract

The first azide(mu1,1)-bridged binuclear cobalt(II) complex with a chelated imino nitroxide radical, [Co2(immepy)2(N3)(4)].2EtOH, was structurally and magnetically characterized, where immepy = 4,4,5,5-tetramethyl-2-(6'-methyl-2'-pyridyl) imidazoline-1-oxyl. Five nitrogen atoms complete the coordination sphere of the Co(II) ion, showing a distorted trigonal bipyramid geometry. Two N(3)(-) anions act as bridges between cobalt ions in the mu1,1 coordination mode, resulting in a binuclear structure with an inversion center. Magnetic studies show that ferromagnetic couplings occurred between the adjacent cobalt(II) ions through N3(-)(mu1,1)) bridges, and antiferromagnetic couplings between the cobalt(II) ions and organic radicals.

Crystal structure of bis(2-{2'-[(l'-methyl)benzimidazolyl]}-4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide)manganese(II) dichloride, Mn(C15H19N4O2)2Cl2

“…Nitronyl nitroxide radicals (NITR), stable organic radicals, have played aprominent role in the design and construction of molecular magnetic materials [2,3]. Up to now, there have been alarge number of investigations with regard to the crystal structures of transition metal complexes with NITR [4][5][6][7]. Therefore, design and syntheses of metalradical compounds may lead to ab etter understanding of magneto-structural correlations.…”

Crystal structure of diazido-tetra(2-(4-pyridyl)4,4,5,5-tetramethyl-imidazoline- 1-oxyl-3-oxide)copper(II), Cu(N3)2(C12H16N3O2)4

“…The design and synthesis of transition metal complexes with organic free radicals is one of the major challenges in the field of molecular magnetic materials [2,3]. Nitronyl nitroxide radicals (NITR), stable organic radicals, have been widely employed as molecular units in the design and synthesis of molecular magnetic materials [4,5].…”

Crystal structure of diaquabis(dicyanamide)-bis(2-(4-pyridyl)- 4,4,5,5-tetramethyimidazoline-1-oxyl-3-oxide)zinc(II), Zn(H2O)2(C2N3)2(C12H16N3O2)2

“…Nitronyl nitroxide radicals (NITR), have played aprominent role in the design and construction of molecular magnetic materials [1,2]. In this field, they have been successful used in conjunction with transition metal ions [3][4][5]. These radicals are especially attractive due to their donor atoms and their ability to assemble extended arrangement with changing magnetic coupling.…”