scholarly journals Synthesis, Structure, and Magnetic Properties of Linear Trinuclear CuII and NiII Complexes of Porphyrin Analogues Embedded with Binaphthol Units

Symmetry ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1610
Author(s):  
Jun-ichiro Setsune ◽  
Shintaro Omae ◽  
Yukinori Tsujimura ◽  
Tomoyuki Mochida ◽  
Takahiro Sakurai ◽  
...  
Keyword(s):  
Variable Temperature ◽  
Macrocyclic Ligand ◽  
Optical Purity ◽  
Antiferromagnetic Coupling ◽  
Central Metal ◽  
Nmr Study ◽  
Square Planar ◽  
Aromatic Components ◽  
Porphyrin Analogues ◽  
Paramagnetic Shifts

A porphyrin analogue embedded with (S)-1,1′-bi-2-naphthol units was synthesized without reducing optical purity of the original binaphthol unit. This new macrocyclic ligand provides the hexaanionic N4O4 coordination environment that enables a linear array of three metal ions. That is, it provides the square planar O4 donor set for the central metal site and the distorted square planar N2O2 donor set for the terminal metal sites. In fact, a CuII3 complex with a Cu(1)–Cu(2) distance of 2.910 Å, a Cu(1)–Cu(2)–Cu(1′) angle of 174.7°, and a very planar Cu2O2 diamond core was obtained. The variable-temperature 1H-NMR study of the CuII3 complex showed increasing paramagnetic shifts for the naphthyl protons as temperature increased, which suggests strong antiferromagnetic coupling of CuII ions. The temperature dependence of the magnetic susceptibility indicated antiferromagnetic coupling both for the CuII3 complex (J = −434 cm−1) and for the NiII3 complex (J = −49 cm−1). The linear (L)M(µ-OR)2M(µ-OR)2M(L) core in a rigid macrocycle cavity made of aromatic components provides robust metal complexes that undergo reversible ligation at the apical sites of the central metal.

Synthesis, structural and magnetic properties of macrocyclic aza-amido binuclear copper(II) complexes

1989 ◽  
Vol 67 (4) ◽  
pp. 662-670 ◽  
Author(s):  
Sanat K. Mandal ◽  
Laurence K. Thompson ◽  
Michael J. Newlands ◽  
Amal K. Biswas ◽  
Bibhutosh Adhikary ◽  
...  
Keyword(s):  
Variable Temperature ◽  
Complex Iii ◽  
Azomethine Nitrogen ◽  
X Ray Diffraction ◽  
Binuclear Copper ◽  
Magnetic Studies ◽  
Monoclinic System ◽  
Space Group ◽  
Pyramidal Geometry ◽  
Square Planar

Binuclear, antiferromagnetically coupled, macrocyclic copper(II) complexes, [Cu2(C28H32N4O4)]•H2O (II) and [Cu2(C36H32N4O4)]•CH3CN•H2O (III), involving asymmetric ligands with two deprotonated amide, two azomethine nitrogen, and two phenoxide donors at the binuclear centre, have been synthesized and characterized by single-crystal X-ray diffraction and variable temperature magnetic studies. Complex II crystallizes in the monoclinic system, space group P21/n, with a = 16.4854(9) Å, b = 7.6005(13) Å, c = 21.1617(11) Å, β = 104.090(5)°, Z = 4, Rf = 0.068 for 2062 significant reflections. The two copper(II) centres have square planar N2O2 donor sets with two phenoxide oxygen atoms bridging the copper centres with a copper–copper separation of 2.898(2) Å. A long copper–oxygen (amide) contact (2.808(10) Å) forms a weak dimer association. Complex III crystallizes in the triclinic system, space group [Formula: see text], with a = 8.7771(9) Å, b = 12.3983(16) Å, c = 15.7299(16) Å, α = 85.003(11)°, β = 84.574(8)°, γ = 76.838(10)°, Z = 2, Rf = 0.041 for 2966 significant reflections. The two copper(II) centres have distorted square-pyramidal geometry involving an N2O2 in plane donor set and two phenoxide oxygen bridges with a copper–copper separation of 3.018(1) Å. The fifth coordination site at each copper centre involves an amide oxygen from a neighbouring molecule (Cu(1)—O 2.371(4), Cu(2)—O 2.413(3) Å) in a staggered intermolecular array. Very strong antiferromagnetic exchange is observed in both cases (−2J = 689 ± 7 cm−1 (II), −2J = 816 ± 8 cm−1 (III)). Keywords: macrocycles, binuclear copper(II) complexes.

scholarly journals Bis phenylene flattened 13-membered tetraamide macrocyclic ligand (TAML) for square planar cobalt(III)

2018 ◽  
Vol 71 (11-13) ◽  
pp. 1822-1836
Author(s):  
W. Chadwick Ellis ◽  
Alexander D. Ryabov ◽  
Andreas Fischer ◽  
Joshua A. Hayden ◽  
Longzhu Q. Shen ◽  
...  
Keyword(s):  
Macrocyclic Ligand ◽  
Square Planar

scholarly journals Variable-Temperature Multinuclear Solid-State NMR Study of Oxide Ion Dynamics in Fluorite-Type Bismuth Vanadate and Phosphate Solid Electrolytes

2019 ◽  
Vol 31 (5) ◽  
pp. 1704-1714 ◽  
Author(s):  
Matthew T. Dunstan ◽  
David M. Halat ◽  
Matthew L. Tate ◽  
Ivana Radosavljevic Evans ◽  
Clare P. Grey
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Solid Electrolytes ◽  
Variable Temperature ◽  
Bismuth Vanadate ◽  
Ion Dynamics ◽  
Nmr Study ◽  
Fluorite Type ◽  
Oxide Ion

Synthesis and Properties of a New Kind of One-Dimensional Conductors. 1. General Aspects

1979 ◽  
Vol 34 (8) ◽  
pp. 983-985 ◽  
Author(s):  
Michael Hanack ◽  
Friedrich Franz Seelig ◽  
Joachim Strähle
Keyword(s):  
Experimental Studies ◽  
Bidentate Ligand ◽  
Central Metal Atom ◽  
Central Metal ◽  
Bridging Ligands ◽  
One Dimensional ◽  
Bridging Ligand ◽  
Linear Chains ◽  
Square Planar ◽  
General Aspects

AbstractA model for a new kind of one-dimensional conductors is presented. The compounds consist of square-planar metal complexes MX4 which are polymerised via bridging ligands L to linear chains. The bidentate ligand L, e.g. C22-, leads to the formation of a linear π-system along the chain, which is essential for the conductivity. The square-planar complex can be, for example, a metal phthalocyanine. MO-calculations show that this kind of polymer gives rise to a suitable energy band structure. An advantage of the new one-dimensional conductors is their flexibility; different combinations of the square-planar ligand system, the bridging ligand, and the central metal atom can be used. First experimental studies show that the preparation of the proposed conductors is possible.

ChemInform Abstract: A VARIABLE TEMPERATURE NMR STUDY OF CARBONYLDIPHENYLACETYLENE TRIS(PI-CYCLOPENTADIENYLRHODIUM) AND ITS BIS(PENTAFLUOROPHENYL)DERIVATIVE

1973 ◽  
Vol 4 (48) ◽  
pp. no-no
Author(s):  
T. YAMAMOTO ◽  
A. R. GARBER ◽  
G. M. BODNER ◽  
L. J. TODD ◽  
M. D. RAUSCH ◽  
...  
Keyword(s):  
Variable Temperature ◽  
Nmr Study

Antiferromagnetic Coupling In A (μ-Hydroxo)(μ-Pyrazolato)Dicopper(II) Complex. Synthesis, Crystal Structure, Magnetic Properties, And Theoretical Studies

2001 ◽  
Vol 56 (8) ◽  
pp. 719-727 ◽  
Author(s):  
H. Kara ◽  
Y. Elerman ◽  
K. Prout
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Variable Temperature ◽  
Magnetic Behaviour ◽  
Antiferromagnetic Coupling ◽  
Theoretical Studies ◽  
Powdered Sample ◽  
Structural Factors ◽  
Binuclear Copper ◽  
Ligand Orbital

Preparation, crystal structure and magnetic properties of a 3,5-dimethylpyrazolate bridged binuclear copper(II) complex [Cu2(L1)(3,5 prz)] (L1 = 1,3-Bis(2-hydroxy-1-napthylideneamino) propan-2-ol) (1) are reported. Variable-temperature magnetic susceptibility measurements for a powdered sample of the complex were carried out in the temperature range 5 - 350 K and analysed to obtain values of the parameter J in the exchange Hamiltonian H = -2JS1·S2 . In the dicopper(II) complex [Cu2(L2)(3,5 prz)], (L2 = l,3-Bis(2-hydroxy-5-chlorosalicylideneamino) propan-2-ol) (2) reported recently the antiferromagnetic interaction is much less than that of 1 (-27 = 440 cm-1 ), as result which is difficult to explain in terms of structural factors on the basis of widely accepted criteria. The differences in the magnetic behaviour now have been rationalized using the “ligand orbital complementary” concept

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