Solvatomorphism and Electronic Communication in FeIII N,N-Bis(salicylidene)-1,3-propanediamine Dimers

2015 ◽  
Vol 68 (5) ◽  
pp. 766 ◽  
Author(s):  
Jitnapa Sirirak ◽  
David J. Harding ◽  
Phimphaka Harding ◽  
Lujia Liu ◽  
Shane G. Telfer

The reaction of H2salpn (H2salpn = N,N′-bis(salicylidene)-1,3-propanediamine) with Fe(ClO4)3 in a ratio of 1 : 1 and 3 : 2, leads to dark red crystals of the solvatomorphs [(salpn)Fe(μ2-salpn)Fe(salpn)]·0.5MeOH (1) and [(salpn)Fe(μ2-salpn)Fe(salpn)]·MeOH (2), respectively. X-Ray crystallographic studies reveal a slightly distorted octahedral geometry and meridional configuration of the N and O donor atoms with one of the salpn ligands acting as a bridge between the two FeIII atoms to create a dimer. The Fe–N/O bond distances for both dimers indicate that the Fe centres are high spin. Supramolecular dimeric pairs are formed in both structures from C–H···π and/or C–H···O interactions. However, the degree of solvation significantly impacts the arrangements of these dimeric pairs with tightly packed 1D chains in 2 and more loosely packed chains in 1. In addition, electrochemical studies reveal weak communication between the two Fe atoms despite the large distance between them and the lack of conjugation across the bridge.

2003 ◽  
Vol 58 (9) ◽  
pp. 916-921 ◽  
Author(s):  
Amitabha Datta ◽  
Samiran Mitra ◽  
Georgina Rosair

Two new bimetallic complexes [Zn(phen)3][Fe(CN)5(NO)] · 2 H2O · 0.25 MeOH, (1) and [(bipy)2(H2O)Zn(μ-NC)Fe(CN)4(NO)] · 0.5 H2O, (2), have been isolated (where phen = 1,10-phenanthroline and bipy = bipyridyl) and characterised by X-ray crystallography [as the 2 H2O · 0.25 CH3OH solvate for (1) and hemihydrate for (2)] infrared spectroscopy and thermogravimetric analysis. Substitution of phenanthroline for bipyridyl resulted in a cyano-bridged bimetallic species rather than two discrete mononuclear metal complexes. The bond angles of Fe-N-O were shown to be practically linear for both 1 [179.2(7)°] and 2 [178.3(3)°], and the Zn atoms have distorted octahedral geometry. The solvent molecules in both crystal lattices take part in forming hydrogen-bonded networks.


1992 ◽  
Vol 45 (11) ◽  
pp. 1933 ◽  
Author(s):  
PR Traill ◽  
AG Wedd ◽  
ERT Tiekink

The characterization of two MoVI complexes, cis -[MoO2(2-pymS)2] and cis -[MoO2(2-pyS)2] (where 2-pymSH is pyrimidine-2-thiol and 2-pySH is pyridine-2-thiol), and their reaction with Ph3P are reported. The X-ray structure of cis -[MoO2(2-pymS)2] shows the molybdenum atom to exist in a distorted octahedral geometry defined by two mutually cis oxygen atoms and two chelating 2-pymS ligands so that the two sulfur atoms occupy approximate trans positions. Crystals of cis -[MoO2(2-pymS)2] are monoclinic, space group P 21/n, with unit cell dimensions: a 9.301(3), b 12.121(2), c 11.303(3) �, β 112.62(3)�, V 1176.3 �3, Z 4. The structure was refined by a full-matrix least-squares procedure to R 0.067 for 1858 reflections with I ≥ 2.5 (I).


2012 ◽  
Vol 67 (3) ◽  
pp. 192-196
Author(s):  
Bao Lin Liu ◽  
Yan Xia Wang ◽  
Ruo Jie Tao

Two new copper(II) complexes, [(CuL)2(μ1,1-N3)2]・2H2O (1) and [Cu(HL)(2,2ʹ-bipy)- (CH3COO)]・ClO4・H2O (2), have been synthesized using the tridentate NNO Schiffbase ligand 2- [(2-aminoethylimino)methyl]-6-methoxyphenol (HL). They have been characterized by elemental analysis, IR spectroscopy, thermal analysis, and single-crystal X-ray analysis. The copper environment is distorted square pyramidal in complex 1: two nitrogen atoms and one oxygen atom from the ligands and two nitrogen atoms from two azido ligands build the coordination polyhedron around the copper atom. The Cu-Nazide-Cu angle in complex 1 is 85.6°. This is unusually small in comparison with the same angle in other end-on doubly azido-bridged dimers. Complex 2 is mononuclear with the Cu atom having a slightly distorted octahedral geometry. Magnetic measurements of 1 have been performed in the temperature range from 2 to 300 K. The experimental data indicate an antiferromagnetic exchange interaction between copper(II) ions bridged by the azido ligand. The best-fit parameters for complex 1 are g = 2.18 and J = −1.31 cm−1.


2014 ◽  
Vol 70 (12) ◽  
pp. 1101-1104 ◽  
Author(s):  
Eduard B. Coropceanu ◽  
Ana Dreab ◽  
Lilia Croitor

Two new mononuclear coordination compounds, bis{4-[(hydroxyimino)methyl]pyridinium} diaquabis(pyridine-2,5-dicarboxylato-κ2N,O2)zincate(II), (C6H7N2O)2[Zn(C7H3NO4)2(H2O)2], (1), and (pyridine-2,6-dicarboxylato-κ3O2,N,O6)bis[N-(pyridin-4-ylmethylidene-κN)hydroxylamine]zinc(II), [Zn(C7H3NO4)(C6H6N2O)2], (2), have been synthesized and characterized by single-crystal X-ray diffractometry. The centrosymmetric ZnIIcation in (1) is octahedrally coordinated by two chelating pyridine-2,5-dicarboxylate ligands and by two water molecules in a distorted octahedral geometry. In (2), the ZnIIcation is coordinated by a tridentate pyridine-2,6-dicarboxylate dianion and by twoN-(pyridin-4-ylmethylidene)hydroxylamine molecules in a distortedC2-symmetric trigonal bipyramidal coordination geometry.


1986 ◽  
Vol 41 (4) ◽  
pp. 523-526 ◽  
Author(s):  
Dieter Fenske ◽  
Kay Jansen ◽  
Kurt Dehnicke

Green crystals of the title compound are formed in the reaction of (PPh4)2 [Mo2(O2C -Ph)4Cl2] ·2 CH2Cl2 with dimethyl formamide/carbon tetrachloride in the presence of water. According to the structural investigations by X-ray methods PPh4[MoCl4(O CHNMe2)] crystallizes orthorhombically in the space group C2221 with four formula units per unit cell (3132 observed, independent reflexions, R - 0.068). The cell dimensions are a = 792.1 pm, b = 1656.8 pm, c = 2211.3 pm. The structure consists of PPh4⊕ cations and anions [MoOCl4(OCHNMe2)]⊖, in which the coordination sphere of the molybdenum atom is of distorted octahedral geometry. The ligands are four equatorial chlorine atoms, one terminal O atom (Mo = O 165 pm) and the O atom of the dimethyl formamide molecule (MoO 232 pm). The IR spectrum is reported


2010 ◽  
Vol 65 (9) ◽  
pp. 1106-1112
Author(s):  
Amitabha Datta ◽  
Sébastien Pillet ◽  
Nien-Tsu Chuang ◽  
Hon Man Lee ◽  
Jui-Hsien Huang

Two new cyano-bridged trinuclear heterometallic complexes [Ca2(phen)4(ClO4)(H2O)3- Fe(CN)6]・H2O (1) and [Ca2 (phen)4(CH3COO)(H2O)3Fe(CN)6]・2H2O (2) (where phen = 1,10- phenanthroline) have been synthesized and characterized by single-crystal X-ray diffraction techniques, IR spectroscopy and thermogravimetric analysis. The structure of complex 1 features a central [Fe(CN)6]3− unit that links a monocation [Ca(phen)2(H2O)(ClO4)]+ and a dication [Ca(phen)2- (H2O)2]2+ via two trans cyanide bridges. Similarly, complex 2 also features a central [Fe(CN)6]3− unit that links a monocation [Ca(phen)2(H2O)(CH3COO)]+ and a dication [Ca(phen)2(H2O)2]2+ via two trans cyanide bridges. In 1 and 2, both Ca centers are seven-coordinated and achieve a pentagonal- bipyramidal geometry whereas the Fe center in both the complexes possesses a distorted octahedral geometry. Intra- and intermolecular hydrogen bonding networks are present in 1 and 2 that impart the overall molecular stability to both the systems.


2016 ◽  
Vol 71 (8) ◽  
pp. 869-874 ◽  
Author(s):  
Gao-Feng Wang ◽  
Xiao Zhang ◽  
Shu-Wen Sun ◽  
Hong Sun ◽  
Xia Yang ◽  
...  

AbstractTwo Mn(II) complexes, {[Mn(BIPMO)2Cl2] · 2(H2O)}n (1) and {[Mn(BIPMO)2(SCN)2] · 2(CH3OH)}n (2) (BIPMO = bis(4-(1H-imidazol-1-yl)phenyl)methanone) with V-shaped BIPMO ligands, were synthesized and characterized by IR spectroscopy and elemental analyses along with their single-crystal X-ray diffraction analyses. The Mn(II) ions in 1 and 2 are both six-coordinated to four nitrogen atoms of four BIPMO ligands and two anions (Cl− for 1, and SCN− for 2) to form a distorted octahedral geometry.


1999 ◽  
Vol 77 (12) ◽  
pp. 2033-2038 ◽  
Author(s):  
Ika A Setyawati ◽  
Steven J Rettig ◽  
Chris Orvig

Iron(III) complexation with potentially hexadentate H2bbpen (N,N'-bis(2-hydroxybenzyl)-N,N'-bis(2-methylpyridyl)ethylenediamine) was studied. The resulting monocationic complex, [Fe(bbpen)]+ as its NO3- and PF6- salts, was characterized by infrared spectroscopy, mass spectrometry, elemental analyses, cyclic voltammetry, and X-ray crystallographic analysis. Crystals of [Fe(bbpen)]NO3·CH3OH are monoclinic, space group P21/c, a = 10.2640(13), b = 14.7526(10), c = 18.3172(5) Å, β = 97.904(1)°, and Z = 4. The structure was solved by heavy-atom Patterson methods and refined to an R factor of 0.039 for 3526 reflections with I > 3σ(I). The structure of the [Fe(bbpen)]+ cation showed that the ligand is bound in a hexadentate fashion to the central Fe(III) ion, resulting in a distorted octahedral geometry. Magnetic susceptibility measurements indicated the presence of a high-spin Fe(III) ion, and the UV-vis spectrum of [Fe(bbpen)]NO3 exhibits absorption maxima, λmax, at 575 nm (ε = 5400 M-1 cm-1), 323 (8900), and 275 (13 500). The cyclic voltammogram of [Fe(bbpen)]NO3 showed a quasi-reversible, one-electron process corresponding to [FeIII(bbpen)]+ + e- <_> [FeII(bbpen)] at -0.47 V vs. SCE.Key words: cationic, iron(III), phenolate, pyridyl, hexadentate.


2020 ◽  
Vol 40 (2) ◽  
pp. 75-89
Author(s):  
Milan Melník ◽  
Marian Koman

AbstractThis review includes 70 monomeric high-spin complexes of the following general compositions: [Fe(II)(η3-pdc)(L)3], [Fe(III)(η3-pdc)(L)3]+, [Fe(II)(η3-pdc)2]2− and [Fe(III)(η3-pdc)2]− (pdc = pyridine-2,6-dicarboxylate (−2)). Each Fe(II) atom has a distorted octahedral geometry. The Fe(III) atoms have a distorted octahedral geometry (most common) and in some examples have a distorted pentagonal-bipyramidal geometry. The chelating donor ligands create varieties of n-membered metallocyclic rings: ONO, OCO, NC2N, OC2N, OC2NO and OC3O. Some cooperative effects between Fe(II) and Fe(III) complexes were found and discussed. There are complexes that are examples of distortion isomerism.


2017 ◽  
Vol 72 (1) ◽  
pp. 83-87 ◽  
Author(s):  
Gao-Feng Wang ◽  
Xiao Zhang ◽  
Zhao-Rong Liu ◽  
Yu-Chun Wang ◽  
Hong-Shi Jiang ◽  
...  

AbstractTwo complexes, {Mn(hfac)2(BIPMO)}n (1), {Cu(hfac)2(BIPMO)}n (2) [hfac=1,1,1,5,5,5-hexafluoro-pentane-2,4-dionato(–), BIPMO=bis(4-(1H-imidazol-1-yl)phenyl)methanone], with the V-shaped ligands were synthesized and characterized by infrared spectroscopy, elemental analyses, along with single-crystal X-ray diffraction analyses. The X-ray diffraction studies have shown that the metal ions in 1 and 2 are both six-coordinated to two nitrogen atoms of two BIPMO ligands and four oxygen atoms of two hfac ligands to form a distorted octahedral geometry. Each BIPMO ligand acts as a bridging ligand to link two adjacent metal(II) atoms to form a helical chain in the crystal structure.


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