Chloride as Supramolecular Glue: Anion‐Directed Assembly of a 2D Network of Mn^III Complexes

Abstract

Abstract The Schiff base H 4 L [where H 4 L = 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 (H 2 L)(CH 3 OH) 2 ]Cl ( 1 ) complex, which was characterized by elemental analysis, FAB mass spectrometry, IR, 1 H 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 N 2 O 2 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−H ··· 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. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)