Jonathan D. Crane

Manganese(II) and iron(III) complexes of the tridentate ligands bis(benzimidazol-2-ylmethyl)-amine (L1) and -methylamine (L2). Crystal structures of [MnL1(CH3CO2)2], [FeL2Cl3], and [Fe2L12(µ-O){µ-(CH3)3CCO2}2][ClO4]2

The preparation and characterisation of [MnL1(CH3CO2)2](1), [Mn6(µ4-O)2(C6H5CO2)10(H2O)4](9), [FeL1Cl3](10), [FeL2Cl3](2), and [Fe2L12(µ-O){µ-(CH3)3CCO2}2][ClO4]2(3) are reported where L1 and L2 are bis(benzimidazol-2-ylmethyl)amine and bis(benzimidazol-2-ylmethyl)methylamine. The molecular structures of (1), (2), and (3) were determined by X-ray diffraction. Complex (1) exists as a discrete, neutral, mononuclear species in the solid state. The manganese(II) ion is five-co-ordinate with the tridentate ligand bound in a meridional manner. Both acetates are monodentate with Mn–O distances of 2.076(5) and 2.158(5)A. Complex (9) contains a [Mn6(µ-O)2]10+ core, formally 4MnII :2MnIII. Complex (2) is neutral, mononuclear, distorted octahedral. The ligand co-ordinates in a similar manner to that seen in (1) and the chlorides occupy the three remaining meridional sites, with Fe–Cl(equatorial) 2.318(5)A and Fe–Cl(axial) 2.322(5) and 2.433(5)A. The Mossbauer spectrum of (10) at room temperature comprises a quadrupole doublet: δ= 0.40(1), ΔEQ= 0.33(2) mm s–1. Complex (3) is a dinuclear iron(III) species containing the triply bridged [Fe2(µ-O)(µ-RCO2)2]2+ core. The Fe ⋯ Fe distance is 3.075(5)A and the Fe–O(oxo)–Fe angle is 117.0(6)°. The high-spin iron(III) centres are antiferromagnetically coupled with J=–116 cm–1. The Mossbauer spectra of (3) at room temperature and 70 K consist of doublets with δ= 0.44(1), ΔEQ= 1.37(2), and δ= 0.55(1), ΔEQ= 1.30(2) mm s–1 respectively.

Preparation and characterisation of C60(ferrocene)2

C60cocrystallises with ferrocene to give black C60(ferrocene)2, which contains discrete C60 and ferrocene molecules; the ferrocene does not reduce C60, but the structure appears to be stabilised as a result of weak intermolecular charge-transfer interactions.

A linear trinuclear mixed oxidation state cobalt(III/II/III) complex with pyrazolate bridging ligands

A linear, trinuclear Co complex with pyrazolate bridges, Co3L2(py)4.6H2O (H4L = 1,3-bis(5-methylpyrazole-3-carboxamido)propane), was prepd. and structurally characterized. The outer Co center is low spin, octahedral Co(III) and is coordinated by a tetra-anionic tetradentate ligand. Two of these outer Co(III) complexes act as bidentate chelating ligands to the central Co(II) ion, which adopts a distorted, flattened, tetrahedral geometry. [on SciFinder(R)]

Homoleptic cobalt(II) and cobalt(III) complexes of the sterically demanding bidentate ligand N-ethyl-2-(2′-hydroxy-3′-methylphenyl)benzimidazole

Abstract Homoleptic cobalt(II) and cobalt(III) complexes of the sterically demanding bidentate ligand N-ethyl-2-(2′-hydroxy-3′-methylphenyl)-benzimidazole (H-ehmpb) are reported. The bis-ligand cobalt(II) complex Co(ehmpb)2 has a distorted tetrahedral geometry with Co–N bond lengths of 1.982(3) and 1.976(3) A, and Co–O bond lengths of 1.915(2) and 1.930(2) A. The tris–ligand cobalt(III) complex Co(ehmpb)3 has a distorted mer-octahedral geometry with Co–N bond lengths of 1.879(6), 1.897(6), and 1.895(6) A, and Co–O bond lengths of 1.923(7), 1.937(7), and 1.937(7) A.

Preparation of the complexes MIIL2·2CH3OH (M = CO, Ni, Cu, Zn) of the bidentate ligand 2-(2′-hydroxy-3′-methylphenyl)-benzimidazole (HL) and the molecular structure of CuIIL2·2CH3OH

Abstract The complexation of the sterically demanding bidentate ligand 2-(2′-hydroxy-3′-methylphenyl)-benzimidazole (HL) with divalent transition metal ions MII (Co, Ni, Cu, Zn), yielded a series of mononuclear complexes of general formula MIIL2·2CH3OH. The crystal structure of the copper(II) complex has been determined and the four coordinate copper(II) centre displays a substantial asymmetric distortion (θ = 39.5°) from a square planar geometry (θ = 0°) towards a tetrahedral geometry (θ = 90°). Crystallographic data: C30H30CuN4O4, Mr = 574.14, triclinic ( P 1 (No. 2))), a = 11.231 (4), b = 15.399 (5), c = 8.194 (4) A , α = 100.68 (3), β = 103.56 (3), γ = 82.96 (3)°, Z = 2, T = 296 K, Dcalc = 1.413 g cm−3, R(Rw) = 0.044 (0.043).

The crystal structure of a µ-phenolato copper(II) dinuclear complex containing two chemically distinct metal co-ordination environments

The crystal structure of [L1Cu2(µ-Br)(µ-HCO2)]2[Cu2Br4](3) is reported, where HL1 is the Schiff base derived from the condensation of 2-aminomethylpyridine and 2-[(N-diethylaminoethyl-N-ethyl)aminomethyl]-4-bromo-6-formylphenol (1); the structure comprises a copper(II) dinuclear cation with phenolate, bromide, and formate bridges in which the metals have different co-ordination environments, and a copper(I) dinuclear dianion with bromide bridges.

Crystallographic characterisation of the lattice structure C60.[Fe4(CO)4(η5-C5H5)4] as the 1/3 benzene solvate

Co-crystallisation of C60 and [Fe4(CO)4(η5-C5H5)4] from benzene solution yields crystals of C60·[Fe4(CO)4(η5-C5H5)4]·3C6H6 containing the ordered lattice structure C60·[Fe4(CO)4(η5-C5H5)4] in which the inter-C60 contacts are resticted to within parrallel double-columnar stacks

Iron(III) and copper(II) complexes of polydentate ligands incorporating benzimidazole and phenolic residues

Abstract The preparation and complexing properties towards iron(III) and copper(II) of the unsymmetric polydentate ligands 1-(2-hydroxy-phenyl)-2-aza-3,5-bis(benzimidazol-2-yl)pentane, H(2), and 1-(2-hydroxy-5-bromo-phenyl)-2-aza-3,5-bis(benzimidazol-2-yl)pentane, H(3), are discussed.

New Chiral Ligands Incorporating Useful Functionality: Racemic Palladium(II) Dichloride Complexes of Bidentate Ligands Containing Two Non-coordinated Ester Groups and Three Chiral Centres of Known Relative Stereochemistry

The cycloaddition of a pyridyl-azomethine to dimethylfumarate produces an approximately equimolar mixture of diastereomeric, C1symmetric, N,N-bidentate ligands. The corresponding palladium(II) dichloride complexes are readily separated by fractional crystallisation and contain non-coordinated ester groups, one of which lies above the plane of the palladium centre. q1999 Elsevier Science S.A. All rights reserved.

Shape selective solvent inclusion within the lattice of bis(N1,N1,N5,N5-tetrabenzyl-2,4-dithiobiureto)nickel(II)

The crystal structure of the stable toluene solvate of bis( N 1 , N 1 , N 5 , N 5 -tetrabenzyl-2,4-dithiobiureto)nickel(II) shows that the solvent molecules are held within lattice cavities of well-defined size and shape. Recrystallisation from a mixture of xylenes was found to yield selectively the p -xylene solvate.