Synthesis and characterization of catalytically active Ni(II) complexes with bis(phenol)diamine ligandsJafari, Zahra (Avtor) Safaei, Elham (Avtor) Wojtczak, Andrzej (Avtor) Zeinalipour-Yazdi, Constantinos D. (Avtor) Kozlevčar, Bojan (Avtor) Jagličić, Zvonko (Avtor) bisphenoldiaminenickel complexesGlaser reactioncoupling of phenylacetyleneferromagnetismgreen procedureA novel N,N’-dimethylethylenediamine derivative of substituted bis(phenol)diamine ligands, namely 2-(tert-butyl)-4-methylphenol in H$_2$L$^1$, was synthesized by a convenient green procedure. Nickel)II) complex [NiL$^1$] 1 has been synthesized and characterized by various methods along with crystal structure determined. Ni(II) coordination center in a mononuclear complex is surrounded by two phenolate oxygen atoms and two amine nitrogen atoms of the ligand in a square planar arrangement. The magnetic susceptibility of the title complex indicates a paramagnetic behavior above 150 K, while strong ferromagnetism below 100 K. Furthermore, the cyclic voltammetry studies show two ligand-centered oxidation of the phenolate groups to phenoxyl radical and the metal-centered reduction of Ni(II) to Ni(0). The Glaser coupling reaction of phenylacetylene was also studied. A strong catalytic activity at room T in THF solvent is observed for 1 in the presence of zinc powder as a reducing agent. A full conversion rate was achieved after 7 h at 25 °C. The DFT analysis corroborates with the square-planar NiO$_2$N$_2$ chromophore of 1 being reduced in catalytically active Ni(0) by applied Zn. The calculated Gibbs free energy of the reaction leading to the formation of the substrate Ni-complex is favorable endothermic. Most of the data for 1 were obtained also for the very similar previously reported [NiL$^2$] 2, with 2,4- di tert-butylphenol in H$_2$L$^2$, which were than compared.20252024-09-12 14:17:30Članek v reviji161611sl