An antiferromagnetically coupled dimeric Ni(II) complex anion and its counter cationic monomeric Ni(II) complex, and some other mononuclear transition metal compounds using some neutral ligands

Synthesis and single crystal X-ray diffraction studies of four transition metal complexes [Mn(L1)](ClO4)2 (1), [Cu(L1)](ClO4)2 (2), [Ni2(L2)(NCS)6][Ni(L1)] (3) and [Mn(bzpy)(NCS)2] (4) with neutral ligands [L1 = N-(1-pyridin-2-yl-phenylidene)-N′-[2-({2-[(1-pyridin-2-yl phenylidene)amino]ethyl}amino)ethyl]ethane-1,2diamine, L2 = N-(1-pyridin-2-yl-phenylidene)-N′-[2-({2-[(1-pyridin-2-ylphenylidene)amino]ethyl}piperazine-1yl)ethyl]amine, bzpy = 2-benzoylpyridine] are reported. The trinuclear nickel(II) complex 3 is made of a dinuclear anion and a mononuclear cation. Variable-temperature magnetic susceptibility and variable-field magnetisation studies performed on 3 suggest weak antiferromagnetic coupling (J = −0.7 cm−1) between the two metals of the dinuclear entity, but no magnetic interaction between the anionic and cationic counterparts.

Graphical abstractSynthesis and single crystal X-ray diffraction studies of four transition metal complexes [Mn(L1)](ClO4)2 (1), [Cu(L1)](ClO4)2 (2), [Ni2(L2)(NCS)6][Ni(L1)] (3) and [Mn(bzpy)(NCS)2] (4) with neutral ligands [L1 = N-(1-pyridin-2-yl-phenylidene)-N′-[2-({2-[(1-pyridin-2-yl phenylidene)amino]ethyl}amino)ethyl]ethane-1,2diamine, L2 = N-(1-pyridin-2-yl-phenylidene)-N′-[2-({2-[(1-pyridin-2-ylphenylidene)amino]ethyl}piperazine-1yl)ethyl]amine, bzpy = 2-benzoylpyridine] are reported. The trinuclear nickel(II) complex 3 is made of a dinuclear anion and a mononuclear cation. Variable-temperature magnetic susceptibility and variable-field magnetization studies performed on 3 suggest weak antiferromagnetic coupling (J = −0.7 cm−1) between the two metals of the dinuclear entity, but no magnetic interaction between the anionic and cationic counterparts.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthetic coordination chemistry. ► Chemistry of Schiff bases as ligands. ► Molecular magnetism.