Dinuclear manganese(II) complexes of 2,6-Bis[2-(dialkylamino)ethyliminomethyl]-4-methylphenolate(1–): synthesis, structure, and magnetism

Abstract

2,6-Bis[2-(dialkylamino)ethyliminomethyl]-4-methylphenolate(1–)[alkyl = methyl (L1) or ethyl (L2)] forms two types of dinuclear manganese(II) complexes [Mn2L(RCO2)2(NCS)](L = L1 or L2, R = CH3 or C6H5) and [Mn2LCl3](L = L1 or L2). The crystal structure of [Mn2L1(CH3CO2)2(NCS)]·H2O·CH3OH has been determined: monoclinic, space group P21/n, a= 17.700(3), b= 12.516(2), c= 15.263(3)Å, β= 107.16(1)° and Z= 4. The X-ray analysis reveals a dinuclear structure bridged by the phenolic oxygen of L1 and two acetate groups. The thiocyanate group co-ordinates to one Mn, resulting in different co-ordination geometries about the two manganese ions, i.e. trigonal bipyramidal and pseudo-octahedral. Magnetic susceptibility measurements over the temperature range 4.2–300 K indicate weak antiferromagnetic interaction (J=–2 to –5 cm–1) for [Mn2L(RCO2)2(NCS)] and no appreciable interaction for [Mn2LCl3].