Synthesis and Characterization of Mononuclear (Mn(II) and Mn(III)) and Dinuclear (Mn(II)Mn(II) and Mn(II)Mn(III)) Complexes with 2,6-Bis[N-(2-pyridylethyl)iminomethyl]-4-methylphenol

Abstract

Mononuclear and dinuclear manganese complexes with2,6-bis[N-(2-pyridylethyl)iminomethyl]-4-methylphenol (HL), [MnII2(L)(CH3COO)2(CH3OH)](ClO4) (1), [MnII2(L)(CH3COO)2(NCS)] (2), [MnII(HL)(NCS)2(H2O)] (3), [MnIIMnIII(L)(CH3COO)2(CH3OH)2](ClO4)2 (4), [MnIIMnIII(L)(CH3COO)2(NCS)2] (5), [MnIIMnIII(L)(CH3COO)2(N3)2]·2CH3OH (6), and [MnIII(HL)(N3)3] (7), have been prepared and characterized by infrared, electronic, and ESR spectra, as well as the temperature dependence of the magnetic susceptibilities (80—300 K). The molecular structures of 1, 2, 3, 6, and 7 were determined by single-crystal X-ray structure analyses. Complexes 1 and 2 have a μ-phenoxo-di-μ-acetato-bridged dinuclear structure, in which one manganese atom is five-coordinated and the other six-coordinated. Complex 6 is a μ-phenoxo-di-μ-acetato-bridged dinuclear molecule comprising an octahedral Mn(II) atom and an elongated-octahedral Mn(III) atom. The manganese atoms of 3 and 7 are six-coordinated in a distorted octahedral environment. The spectral and magnetic properties are discussed in relation to the crystal structures.

Polynuclear MnII Complexes with Chloroacetate Bridge − Syntheses, Structure, and Magnetic Properties

“…When a third bridging ligand is present, e.g. another carboxylate,9,16−18 aqua,5−7 hydroxo,8,9 or phenoxo10−13 group, the Mn ··· Mn distance becomes smaller (4.03−3.35 Å).…”

“…Some dinuclear complexes with carboxylate bridges are reported in the literature, with [Mn 2 (μ‐H 2 O)(μ‐RCOO) 2 ] 2+ ,5−7 [Mn 2 (μ‐OH)(μ‐RCOO) 2 ] + ,8,9 and [Mn 2 (μ‐OR)(μ‐RCOO) 2 ] + cores 10−14. There are also some dinuclear compounds which only have carboxylate bridges, e.g.…”

Synthesis, Crystal Structures and Magnetic Properties of Mixed-Valent Tetranuclear Complexes with Y-Shaped MnII2MnIII2 Core

“…All of the J values except for J 5 are negative, in accord with overall antiferromagnetic couplings in 1, 2, 3, and 4. Larger −J 1 values are understandable, because antiferromagnetic coupling between Mn III and Mn III is usually stronger than that between Mn II and Mn III or Mn II [17,19]. A ferromagnetic coupling was observed for J 5 .…”

“…Many kinds of tetranuclear Mn II 2 Mn III 2 complexes have appeared in the literature, and butterfly-shaped tetranuclear Mn II 2 Mn III 2 complexes have remarkable magnetic properties with ferromagnetic couplings and SMM behavior [13][14][15]. Based on this background, we have focused on the synthesis of manganese complexes with multidentate organic ligands [16][17][18][19][20][21][22][23][24][25][26][27][28]. We and other researchers have studied coordination compounds based on a multidentate Schiff-base, 1,3-bis(salicylideneamino)-2-propanol, as a dinucleating ligand to make mononuclear, dinuclear, tetranuclear, and polynuclear manganese complexes [16, [29][30][31][32].…”

μ-Phenolato-μ-chlorido-bridged Dinuclear Manganese(II) Complex with a Dinucleating Schiff-base Ligand Having Imidazolyl Groups

“…The complex was isolated from the template reaction of 2,6-diformyl-4-methylphenol (9 mg, 0.05 mmol), 10 histamine dihydrochloride (19 mg, 0.1 mmol), manganese(II) perchlorate hexahydrate (37 mg, 0.1 mmol), sodium cyanate (19 mg, 0.3 mmol), and three drops of tetrabutylammonium hydroxide in a mixed solution of methanol (1 cm 3 ) and acetonitrile (3 cm 3 ) as yellow crystals.…”