Synthesis, structure and magnetic properties of two end-on double azido bridged nickel(II) dinuclear entities incorporating N,N,N-coordinating tridentate reduced Schiff base ligands

Complexes of the general formula [Ni2L2(μ1,1-N3)2(N3)2] have been synthesised in good yields by reacting Ni(NO3)2 · 6H2O with L in the presence of excess of sodium azide in methanol at room temperature. Here L is N,N-bis(2-pyridylmethyl)amine (L1) and N-(2-pyridylmethyl)-N′,N′-diethylethylenediamine (L2). The X-ray structures of both compounds reveal that the N,N,N coordinating reduced Schiff bases are ligated facially. The Ni–Nazido–Ni angle is ∼100° and the Ni⋯Ni separation is ∼3.2 Å. The variable temperature magnetic susceptibility measurements of the two complexes show ferromagnetic behavior.

Graphical abstractThe reaction of Ni(NO3)2 · 6H2O with N,N,N-coordinating reduced Schiff base ligands in methanol in the presence of excess azide afforded μ1,1-N3 bridged dinuclear nickel(II) complexes in excellent yields. Variable temperature magnetic susceptibility measurements confirm the ferromagnetic behavior of the complexes.Figure optionsDownload full-size imageDownload as PowerPoint slide