Syntheses and X-ray structural studies of the novel complexes [Ni(en)2(3-pyt)2] and [Cu(en)2](3-pyt)2 based on 5-(3-pyridyl)-1,3,4-oxadiazole-2-thione

Two novel mononuclear mixed-ligand complexes [Ni(en)2(3-pyt)2] (1) and [Cu(en)2](3-pyt)2 (2), derived from potassium [N′-(pyridine-3-carbonyl)-hydrazinecarbodithioate [K+(H2L)−] and containing en as a co-ligand, have been synthesized. The [K+(H2L)−] undergoes cyclization in the presence of ethylenediamine (en) and is converted to 5-(3-pyridyl)-1,3,4-oxadiazole-2-thione (3-pyt)−. [Ni(en)2(3-pyt)2] and [Cu(en)2](3-pyt)2 have been characterized with the aid of elemental analyses, IR, UV–Vis, magnetic susceptibility and single crystal X-ray studies. The complexes 1 and 2 crystallize in the orthorhombic and monoclinic systems with space groups Pca2(1) and C2/c, respectively. The single crystal X-ray diffraction studies of both complexes indicate that (3-pyt)− adopts a thione form in 1 but is present as a thiolato form in 2.

Graphical abstractTwo novel mononuclear mixed-ligand complexes [Ni(en)2(3-pyt)2] (1) and [Cu(en)2](3-pyt)2 (2), based on 5-(3-pyridyl)-1,3,4-oxadiazole-2-thione (3-pyt)−, have been synthesized and their crystal structures reported. The ligand (3-pyt)− is bonded through the oxadiazole nitrogen in the thione form in 1 and is ionically present in the thiolate form in 2.Figure optionsDownload full-size imageDownload as PowerPoint slide