Dinuclear Manganese(III) Complex with a Schiff-base Having a Di-μ-acetato-μ-alkoxido-bridged Core

The chemistry of mononuclear, dinuclear, and tetranuclear manganese complexes with organic ligands is interesting, having relevance to some active centers in biological systems, such as superoxide dismutase, catalase, and the oxygen-evolving complex (OEC) of photosystem II (PSII) in green plants.1 So far, mononuclear, dinuclear, tetranuclear, and polynuclear manganese complexes with dinucleating Schiff-base ligands having a bridging alkoxido-oxygen, 1,3-bis(salicylideneamino)2-propanol (H3sap) and its substituent derivatives, have appeared in the literature.2–8 In this study, we isolated a new dinuclear manganese complex with 1,3-bis(3-methoxysalicylideneamino)2-propanol (H3msap) and determined the crystal structure, which shows a dinuclear core with one alkoxido-oxygen and two-μ-acetato bridges, as shown in Fig. 1. This paper describes the synthesis, crystal structure and electronic spectra of [Mn2(msap)(μ-CH3COO)2(CH3COO)(CH3OH)] (1). The ligand H3msap was synthesized by a method described in the literature.7 The complex was prepared by a 1:2 reaction of H3msap and manganese(II) salt. To an acetonitrile solution (2 cm3) of H3msap (18.0 mg, 0.05 mmol) was added an absolute methanol solution (1 cm3) of 24.9 mg (0.1 mmol) of manganese(II) acetate tetrahydrate, and then three drops of 2020 © The Japan Society for Analytical Chemistry