Crystal Structure and Magnetic Property of the Binuclear Manganese(III) Complex with /u-Acetate and Di-ji-Alkoxo Bridges

Multinuclear manganese sites that are involved in the catalysis of reactions vital to biological systems are being steadily recognized and studied. Besides the photosynthetic water-oxidizing complex, which is known to utilize 4 Mn ions for the oxidation of water to molecular oxygen [1], evidence has accumulated that the Mn site of the pseudo-catalase from Lactobacillus planatrum is comprised of two Mn ions per protein subunit [2]. Thus there is compelling interest in the characterization of multinuclear manganese complexes in various oxidation states in order to unravel the more complex behaviour of the biological sites by serving as models of the structural, spectral, of functional properties. In the previous papers, Nishida et al. have studied the catalytic function of binuclear Mn(III) complexes for the decomposition of H 2 0 2 [3], and the ESR spectra of binuclear Mn(II) [4], and Mn(III) [5] complexes. In this article we wish to report the preparation, crystal structure, and magnetic properties of the binuclear manganese(III) complex, [Mn2L(/*-0CH3)(//-CH3C00)(0HCH3)]C104 where H3L represents the Schiff base derived from salicylaldehyde and 1.5-diamino-3-pentanol.