Chloride as supramolecular glue:: Anion-directed assembly of a 2D network of MnIII complexes

The Schiff base H4L [where H4L = N,N'-bis(3-hydroxysalicylidene) ethane-1, 2-diamine], containing six potential donor atoms, is able to induce the formation of a novel [Mn-III(H2L)(CH3OH)(2)]Cl (1) complex, which was characterized by elemental analysis, FAB mass spectrometry, IR, H-1 NMR and electronic spectroscopy, magnetic measurements, X-ray diffraction techniques and conductivity measurements. The study of its redox properties by cyclic and normal pulse voltammetry is also reported. The crystal structure of 1 is formed by monomeric cationic Mn-III complexes, where the manganese ion is in an octahedral environment and is coordinated in the equatorial plane to the N2O2 donor set of the inner Schiff-base compartment. The neutral condition of the complex is achieved with the presence of the chloride counterion, which behaves as a multiple acceptor of hydrogen bonds. The chloride is involved in four O-(HCl)-Cl-... bonds, connecting three neighbouring cationic complexes. To the best of our knowledge, this constitutes the first example of self-assembly of discrete units of Mn-III complexes in a 2D network in the solid state through hydrogen bonding, where the anion is acting as a supramolecular glue.