Synthesis, structure and properties of [ML(NO3)2]: M = Co, Ni, Cu; L = N-(2-pyridylethyl)pyridine-2-carbaldimine

Syntheses of complexes of the type [ML(NO3)2], where M = Co(II), Ni(II), and Cu(II), L = N-(2-pyridylethyl)pyridine-2-carbaldimine, a tridentate ligand, are described. They were characterized by elemental analysis, spectral, magnetic, thermal studies, and X-ray crystallography. In the cobalt (1), nickel (2), and copper (3) complexes, the bivalent metal ion is coordinated by the three nitrogen atoms of the tridentate L with two pyridine-N groups occupying trans positions. Amongst the two nitrates one coordinates in a bidentate fashion while the other adopts a monodentate fashion. The X-band EPR spectra of 1, 2, and 3 in the polycrystalline state and in acetonitrile solution at 77 K are reported. Room temperature vibrating sample magnetometer data of 1, 2, and 3 afforded μeff values respectively of 3.928, 3.897, and 1.952 BM. The thermal stability order is 1 > 2 > 3, showing a reverse Irving-Williams trend.

Graphical abstractComplexes of the type [ML(NO3)2], {M = Co(II), Ni(II), and Cu(II), L = N-(2-pyridylethyl)pyridine-2-carbaldimine} have been synthesized and characterized by spectral, magnetic, and X-ray crystallographic methods. In the cobalt (1), nickel (2), and copper (3) complexes, the bivalent metal ion is coordinated by the three nitrogen atoms of the tridentate L with two pyridine-N occupying trans positions. Amongst the two nitrates one coordinates in a bidentate fashion while the other coordinates in a monodentate fashion.Figure optionsDownload full-size imageDownload as PowerPoint slide