The title compound was synthesized by the reaction between a manganese(II) carboxylate and the tetradentate Schiff base ligand, 5-Br-salpnH2 [N,N′-bis(5-Br-salicylidene)-1,3-diaminopropane] produced in situ. The complex crystallizes in the P21/c space group with unit cell dimensions (10), (10), (3), , (10), and . The manganese(III) ion is in a distorted octahedral environment with longer axial bonds. 1. Introduction Recent advances in the coordination chemistry of manganese has been intimately connected to diverse fields such as, asymmetric catalysis [1, 2], molecular magnetism [3–5], and bioinorganic modeling [6–8]. With its accessible oxidation states of (II), (III), (IV), and (V), manganese plays several important roles in biological systems like the oxygen-evolving complex (OEC) of photosystem II [9, 10] and enzymes like superoxide dismutase, catalase, and arginase [11, 12]. Active sites of most of these systems contain manganese ligated mainly by N and O-donor atoms from the amino acid residues of the metalloproteins. Inorganic model complexes have made significant contributions to the progress in delineating the structural and functional aspects of the active sites of these systems [13–16]. Ligands such as aliphatic, cyclic Schiff bases, polypyridyl systems, and carboxylic acids can stabilize manganese in its various oxidation states [17, 18]. Schiff base ligands with nitrogen and oxygen donor atoms may provide a chemical environment which can mimic the coordination spheres of manganese in biological systems better than any other ligand type. A whole host of manganese Schiff base complexes have been reported in this context during the last few decades [19–27]. Among these, there is a sizeable number of complexes of the salpn [salpnH2 = -bis (salicylidene)-1, 3-diaminopropane] and substituted salpn ligands [19–22]. We have been interested in the coordination chemistry of higher oxidation states of manganese for some time, and herein, we report the isolation of a new manganese(III) complex, [ (5-Br-salpn)(DMF)2][B(C6H5)4]. 2. Experimental 2.1. Materials and Physical Measurements All chemicals were purchased from E-Merck and used without further purification. IR spectrum was recorded on a Nicolet 6700 spectrophotometer (KBr pellets, 4000–400？cm？1) while UV-Vis spectrum was taken on a Cary 100 Bio UV-Vis spectrophotometer. Elemental analyses were performed using a Perkin-Elmer 2400？CHNS analyzer. 2.2. Synthesis of [MnIII(5-Br-salpn)(DMF)2][B(C6H5)4] The starting material, [Mn2(Hsal)4(H2O)4], was prepared as reported earlier or alternatively by mixing
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