Synthesis, thermal analysis, spectroscopy and magnetic properties of some transition metals complexes derived from new azo compound

A new Azo compound (C-17 H13ClN2O4S) (E)-4-chloro-5-((2-hydroxynaphthalen-1-yl)diazenyl)-2-methyl benzenesulfonic acid (L) was synthesized. The prepared compound was used as a ligand to prepare monomeric transition complexes [M(L)(H2O)(2)Cl-2 via reaction of ligand (L) with hydrate metal salts M (II) where [M = Manganese (II), Cobalt(II), Nickel(II), Copper (II)] in a (1:1) ratio. The data were obtained from C-13 NMR, UV-VIS and FT-IR studies, elemental microanalysis, TGA, molar conductance, metal content, magnetic moment measurements and thermal analysis confirmed the formation of ligand and their complexes and all the prepared complexes have octahedral geometrical structures. The FTIR spectra revealed that ligand to the metals in a uninegative bidentate, with N donor sites of azo group and the deprotonated naphtholic O. The data of thermal analysis shows that the water molecules (coordinated & hydrated) and anions are removed in a successive one or two steps immediately followed by decomposition of ligand in the consecutive steps. The magnetic moment values at room temperature of synthesized complexes are 5.2, 4.3, 3.2 and 1.3 B.M for complexes Mn(II), Co(II), Ni(II) and Cu(II), respectively, suggesting that the complexes are paramagnetic. (C) 2019 Elsevier Ltd. All rights reserved.