Date Published: August 01, 2012
Publisher: International Union of Crystallography
Author(s): Akbar Ghaemi, Saeed Rayati, Kazem Fayyazi, Seik Weng Ng, Edward R. T. Tiekink.
Two distinct coordination geometries are found in the binuclear title complex, [Ni2(C13H19N2O2)2(N3)2(CH3OH)], as one Schiff base ligand is pentadentate, coordinating via the anticipated oxide O, imine N and amine N atoms (as for the second, tridentate, ligand) but the oxide O is bridging and coordination also occurs through the methoxy O atom. The NiII atoms are linked by a μ2-oxide atom and one end of a μ2-azide ligand, forming an Ni2ON core. The coordination geometry for the NiII atom coordinated by the tridentate ligand is completed by the methoxy O atom derived from the pentadentate ligand, with the resulting N3O3 donor set defining a fac octahedron. The second NiII atom has its cis-octahedral N4O2 coordination geometry completed by the imine N and amine N atoms of the pentadentate Schiff base ligand, a terminally coordinated azide N and a methanol O atom. The arrangement is stabilized by an intramolecular hydrogen bond between the methanol H and the oxide O atom. Linear supramolecular chains along the a axis are formed in the crystal packing whereby two amine H atoms from different amine atoms hydrogen bond to the terminal N atom of the monodentate azide ligand.
For background to azido derivatives of tridentate Schiff base NiII complexes, see: Ribas et al. (1999 ▶); Koner et al. (2009 ▶); Biswas et al. (2011 ▶). For a related structure, see: Ghaemi et al. (2012 ▶).