Synthesis, characterization, and magnetic properties of new homotrinuclear bis(oxamato) copper(II) complexes with an asymmetric central N, N′-bridge

• Published in: Inorganica Chimica Acta Vol. 360; no. 12; pp. 3777 - 3784
• Main Authors: Rüffer, Tobias, Bräuer, Björn, Eya’ane Meva, François, Walfort, Bernhard, Salvan, Georgeta, Powell, Annie K., Hewitt, Ian J., Sorace, Lorenzo, Caneschi, Andrea
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2007
• Subjects: Copper; Flexidentate ligands; Magnetochemistry; Oxamato ligands; X-ray diffraction; Flexidentate ligands; Magnetochemistry; X-ray diffraction; Oxamato ligands; Copper
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/j.ica.2007.05.043

The new mononuclear bis(oxamato) complex [ n-Bu 4N] 2[Cu(obbo)] ( 1) (obbo = o-benzyl-bis(oxamato)) has been synthesized as a precursor for trinuclear oxamato-bridged transition metal complexes. Starting from 1 the homotrinuclear complexes [Cu 3(obbo)(pmdta) 2(NO 3)](NO 3)·CH 2Cl 2·H 2O ( 2) and [Cu 3(obbo)(tmeda) 2(NO 3) 2(dmf)] ( 3) have been prepared, where pmdta = N, N, N′, N″, N″-pentamethyldiethylenetriamine, tmeda = N, N, N′, N′-tetramethylethylenediamine and dmf = dimethylformamide. The crystal structures of 1– 3 were solved. The magnetic properties of 2 and 3 were studied by susceptibility measurements versus temperature. For the intramolecular J parameter, values of −111 cm −1 ( 2) and −363 cm −1 ( 3) were obtained. The new mononuclear bis(oxamato) complex [ n-Bu 4N] 2[Cu(obbo)] ( 1) (obbo= o-benzyl-bis(oxamato)) has been synthesized as a precursor for trinuclear oxamato-bridged transition metal complexes. Starting from 1 the homotrinuclear complexes [Cu 3(obbo)(pmdta) 2(NO 3)](NO 3)·CH 2Cl 2·H 2O ( 2) and [Cu 3(obbo)(tmeda) 2(NO 3) 2(dmf)] ( 3) have been prepared, where pmdta = N, N, N′, N″, N″-pentamethyldiethylenetriamine, tmeda = N, N, N′, N′-tetramethylethylenediamine and dmf = dimethylformamide. The crystal structures of 1– 3 were solved. The magnetic properties of 2 and 3 were studied by susceptibility measurements versus temperature. For the intramolecular J parameter values of −111 cm −1 ( 2) and −363 cm −1 ( 3) were obtained.