Trinuclear Manganese Research Articles

Synthesis and structure of a trinuclear manganese(II) complex containing low-spin metal

The reaction of α-phenylazobenzaldehyde oxime, HL, with manganese(II) salts has afforded the first known mixed-spin trinuclear complex [MnII3L6]. The structure of the benzene solvate [Mn3L6]·2C6H6 has been determined by X-ray crystallography. The Mn3 fragment is exactly linear with the terminal low-spin (S=½) metal(II) atoms tris-chelated by azo- and oxime-nitrogen functions into facial pseudo-octahedral MnN6 dispositions. Two such [MnL3]– moieties sequester the central high-spin (S=5//2) manganese(II) atom into an O6 environment using oximato oxygen donors. The average Mn ⋯ Mn, Mn–N, and Mn–O distances are 3.577(7), 1.956(18), and 2.146(15)A respectively. It is proposed that oximato nitrogen co-ordination is primarily responsible for the low-spin configuration of the terminal manganese(II) atoms.

Dinuclear Cobalt(II), Iron(II), and Manganese(II), and Trinuclear Manganese(II) Complexes with Tridentate Ligands of NNS-Donor Set Derived from 2-Aminoethanethiol

Abstract Thiolate-bridged dinuclear cobalt(II), iron(II), and Manganese(II) complexes and trinuclear manganese(II) complexes of thiolic ligands, 2-[(2-aminoethyl)amino]ethanethiol, 2-[(3-aminopropyl)amino]ethanethiol, 2-[(2-pyridylmethyl)amino]ethanethiol, and 2-[[(2-pyridylethyl]amino]ethanethiol, were prepared and their magnetic properties were examined in the temperature range 80–300 K. The results indicated a significant antiferromagnetic spin-exchange interactions through the bridging sulfur atom for all the complexes.

ChemInform Abstract: Isolation of a Mixed‐Valence Trinuclear Manganese Complex Potentially Relevant to the Photosynthetic Oxygen‐Evolving Complex.

AbstractThe title complex (I) is obtained by refluxing a methanolic solution of the Schiff base ligand with Mn(OAc)2 followed by air oxidation.

Isolation of a mixed-valence trinuclear manganese complex potentially relevant to the photosynthetic oxygen evolving complex

In order to better understand the mechanism of the oxygen-evolving complex (OEC) in the photosynthesis process, a manganese compound Mn/sup II/Mn/sup III/(SALADHP)/sub 2/(O/sub 2/CCH/sub 3/)/sub 4/(CH/sub 3/OH)/sub 2/, H/sub 2/SALADHP = 2-(salicylideneamino)-1,3-dihydroxy-2-methylpropane, has been prepared and characterized. This complex is the first reported multinuclear manganese species that has a ground state and a low-lying excited state and gives rise to a low field EPR signal. This illustrates that such a trinuclear formation could generate the nuclear behavior previously reported for the OEC. 32 refs., 3 figs.

Discrete oxidation states and X-ray crystal structure of the trinuclear manganese carboxylate [Mn3(3-ClC5H4N)3O(O2CMe)6

The antiferromagnetic MnII,III,III complex [Mn3(3-Clpy)3O(O2CMe)6], prepared by the reaction of 3-chloropyridine with [Mn(H2O)2(O2CMe)3], possesses a molecular structure, determined by X-ray methods, in which a manganese(II) atom can be clearly distinguished from two manganese(III) atoms.