Pseudohalide manganese(II) complexes of 2-hydroxymethylbenzimidazole – Synthesis, spectroscopy, X-ray structure and magnetic properties

• Published in: Polyhedron 2014-10, Vol.81, p.465-474
• Main Authors: Palion-Gazda, J., Machura, B., Klemens, T., Kłak, J.
• Format: Article
• Language: English
• Subjects: 2-Hydroxymethylbenzimidazole; Magnetic properties; Manganese(II) complexes; Pseudohalide ligands; X-ray
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2014.06.020

The paper concerns three new manganese(II) complexes of 2-hydroxymethylbenzimidazole [Mn(hmbzim)2(NCS)2] (1), [Mn2(hmbzim)4(μ1,1-N3)2](NO3)2 (2) and [Mn(hmbzim)2(dca)2]n (3) characterised by X-Ray analysis, IR, UV–Vis and magnetic measurements. On the basis of structural data, the influence of pseudohalide ions on a final complex structure and role of weak intermolecular interactions in creation of molecular architecture have been discussed. Magnetic measurements revealed ferromagnetic coupling (J=0.82(1)cm−1) inside the dimer of 2 and weak antiferromagnetic coupling (J=−0.37(1)cm−1) in 2D lattice of 3. The complex 1 indicated a very small antiferromagnetic interaction between MnII ions transmitted in the crystal lattice. [Display omitted] Three new manganese(II) complexes of 2-hydroxymethylbenzimidazole [Mn(hmbzim)2(NCS)2] (1), [Mn2(hmbzim)4(μ1,1-N3)2](NO3)2 (2) and [Mn(hmbzim)2(dca)2]n (3) were synthesized and characterised. On the basis of structural data, the influence of pseudohalide ions on a final complex structure and role of weak intermolecular interactions in creation of molecular architecture have been discussed. The structure 1 consists of the mononuclear molecules [Mn(hmbzim)2(NCS)2] assembled via O–H⋯S and N–H⋯S hydrogen bonds into three dimensional supramolecular network The reaction with using of sodium azide resulted in formation of 0D dimeric structure of 2, whereas the complex 3 incorporating dicyanamide ions displays two-dimensional coordination framework. Magnetic measurements revealed ferromagnetic coupling (J=0.82(1)cm−1) inside the dimer of 2 and weak antiferromagnetic coupling (J=−0.37(1) cm−1) in 2D lattice of 3. The complex 1 indicated a very small antiferromagnetic interaction between MnII ions transmitted in the crystal lattice.