ChemInform Abstract: Synthesis and X-Ray Structures of Tetralithium Derivatives of tert- Butylcalix(4)arene Containing Unique Li-O Cores Based on a Square- Pyramidal Geometry.

ChemInform ◽  
2010 ◽  
Vol 28 (51) ◽  
pp. no-no
Author(s):  
M. G. DAVIDSON ◽  
J. A. K. HOWARD ◽  
S. LAMB ◽  
C. W. LEHMANN
2021 ◽  
Vol 33 (2) ◽  
pp. 359-366
Author(s):  
Habibar Chowdhury ◽  
Chandan Adhikary

Two copper(II) azido complexes of the types mononuclear [Cu(TMEDA)2(N3)2] (1) and dinuclear [Cu(TMEDA)(μ1,1-N3)(N3)]2 (2) [TMEDA = trimethylenediamine; N3 – = azide ion] have been synthesized and characterized. X-ray structural analysis revealed that each copper(II) center in complex 1 adopts a distorted octahedron geometry with a CuN6 chromophore ligated through four N atoms of two different symmetrical TMEDA ligands as bidentate chelator and two N atoms of two terminal azides. In complex 2, each copper(II) center adopts a distorted square pyramidal geometry with a CuN5 chromophore ligated through two N atoms of TMEDA as bidentate chelator and two N atoms of two different azides as μ1,1-N3 bridging mode and one N atom of terminal azide ion. The two copper centers are connected through double μ1,1-N3 bridges affording a dinuclear structure with Cu···Cu separation 3.327(2) Å. In crystalline state, mononuclear units in complex 1 are associated through intermolecular N-H···N and C-H···N hydrogen bonds to form a 2D sheet structure viewed along crystallographic b-axis, whereas dinuclear entities in complex 2 are propagated through intermolecular N-H···N and C-H···N hydrogen bonds to form a 3D network structure viewed along crystallographic a-axis. The Variable-temperature magnetic susceptibility measurement evidenced a dominant antiferromagnetic interaction between the metal centers through μ1,1-azide bridges in complex 2 with J = − 0.40 cm-1. The antibacterial activities of the complexes have also been studied.


1984 ◽  
Vol 57 (6) ◽  
pp. 1454-1458 ◽  
Author(s):  
Yuji Kajikawa ◽  
Tosio Sakurai ◽  
Nagao Azuma ◽  
Shizue Kohno ◽  
Sei Tsuboyama ◽  
...  

2020 ◽  
Vol 42 (6) ◽  
pp. 928-928
Author(s):  
Fouzia Chang Fouzia Chang ◽  
Najma Memon Najma Memon ◽  
Shahabuddin Memon Shahabuddin Memon ◽  
Muhammad Naeem Ahmed Muhammad Naeem Ahmed ◽  
Muhammad Nawaz Tahir Muhammad Nawaz Tahir ◽  
...  

A novel Poly [bis-and#181;-3,5-dinitro-2-oxidobenzoato) (py) Cu II]/(C12H7CuN3O7) was synthesized by a self assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P 2 1/c with lattice parameters of a = 10.2143, b = 5.1651 and c = 26.608, α = 90, β = 99.720, γ = 90, Z = 4, V = 1383.60 (18) and#197;3.Pore size depicted from single crystal XRD data was 47and#197;. The central metal atom Cu (II) is coordinated with oxygen of carboxylates group and nitrogen atom of pyridine. The coordination polyhedron posses square pyramidal geometry is manifested by the N— Cu—O angle of 90o. The structure is composed of monomeric coordination units with the central copper (II) ion is not occupying a centre of symmetry.


1999 ◽  
Vol 54 (9) ◽  
pp. 1170-1174 ◽  
Author(s):  
Arto Maaninen ◽  
René T. Boeré ◽  
Tristram Chivers ◽  
Masood Parvez

The reaction of SeCl4 or SeCl2 with N,N′-bis(trimethylsilyl)-2,6-diisopropylaniline occurs not at the nitrogen atom but by electrophilic aromatic substitution at C-4 of the phenyl ring to give [(CH3)3Si]2NC6H2 (iPr2)SeCl3 , which crystallizes as the chloro-bridged dimer in the triclinic system, space group P1̅, a - 10.2598(17), b = 13.665(3), c = 9.7838(10) Å, a = 90.056(13), ß = 102.439(11), γ = 70.922(14)°, V = 1262.3(4) Å3, Z= 1. The dimer contains an essentially planar Cl2Se(μ-Cl)2SeCl2 unit, with trans apical (Me3Si)2NC6H2(iPr)2 groups, resulting in approximately square pyramidal geometry at Se. The bridging Se-Cl distances are unequal at 2.587(2) and 2.749(2) Å.


2015 ◽  
Vol 71 (9) ◽  
pp. 1100-1104
Author(s):  
Bryan Brautigam ◽  
Chelsea Herholdt ◽  
William Farnsworth ◽  
Ellen Brudi ◽  
Eric McDonald ◽  
...  

The title compound, [CoFe(C5H5)(C16H14N2O2)(C11H9N2O)], was prepared as an air-stable red–brown solid by mixing equimolar amounts of {2,2′-[ethane-1,2-diylbis(nitrilomethanylylidene)]diphenolato}cobalt(II) andN-ferrocenylisonicotinamide in dry dichloromethane under nitrogen and was characterized by ESI–MS, IR, and single-crystal X-ray diffraction. The structure at 100 K has triclinic (P-1) symmetry and indicates that the complex crystallizes as a mixture of λ and δ conformers. It exhibits the expected square pyramidal geometry about Co, and forms hydrogen-bonded dimers through amide N—H groups and phenolate O atoms on an adjacent molecule. The involvement of only half of the salen ring structure in hydrogen-bonding interactions results in slight folding of the salen ring away from the pyridine coordination site in the δ conformer with an inter-salicylidene fold angle of 9.9 (7)°. In contrast, the λ conformer is nearly planar. The dimers pack into an open structure containing channels filled with highly disordered solvent molecules. These solvent molecules' contributions to the intensity data were removed with the SQUEEZE procedure [Spek (2015).Acta Cryst.C71, 9–18] available inPLATON.


1998 ◽  
Vol 63 (3) ◽  
pp. 356-362 ◽  
Author(s):  
Svetlana Pakhomova ◽  
Jan Ondráček ◽  
František Jursík

Single-crystal X-ray diffraction study established the dimeric [Cu2(ohb-(S)-Ala)2] structure (ohb-(S)-Ala = N-(2-hydroxybenzyl-(S)-alaninate). The complex crystallizes in the tetragonal space group P43212 with a = b = 8.849(1) Å, c = 24.913(2) Å, V = 1950.8(3) Å3, Z = 8. The Cu(II) ion has distorted square-pyramidal geometry with the equatorial positions occupied by three oxygen and one nitrogen atom. Each copper atom is weakly coordinated at the apical position by carbonyl oxygen atom of the neighbouring molecule at the distance 2.329(2) Å. The Cu-Cu separation 3.0204(7) Å and the Cu-O3-Cu angle 100.8(1)° lead to antiferromagnetic coupling (at room temperature μeff = 1.35 μB). The O1-Cu-O3 angle (154.9(1)°) indicates distortion of the square pyramid toward a trigonal bipyramid (t = 0.23).


Inorganics ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 37 ◽  
Author(s):  
Kiyoshi Fujisawa ◽  
Tetsuya Ono ◽  
Moemi Okamura

Three catecholato copper(II) complexes, [Cu(catCl4)(L1′)], [Cu(catBr4)(L1′)], and [Cu(catCl4)(L1H)], supported by sterically hindered neutral and anionic N3 type ligands: tris(3,5-diisopropyl-1-pyrazolyl)methane (referred to as L1′) and hydrotris(3,5-diisopropyl-1-pyrazolyl)borate (referred to as L1−), are synthesized and characterized in detail. Their X-ray structures reveal that both [Cu(catCl4)(L1′)] and [Cu(catBr4)(L1′)] complexes have a five-coordinate square-pyramidal geometry and [Cu(catCl4)(L1H)] complex has a four-coordinate square-planar geometry. The L1H is unusual protonated ligand that controls its overall charge. For the three catecholato copper(II) complexes, the oxidation state of copper is divalent, and catechol exists in catecholate as two minus anion. This difference in coordination geometry affects their d-d and CT transitions energy and ESR parameters.


2017 ◽  
Vol 41 (19) ◽  
pp. 10890-10898 ◽  
Author(s):  
Malay Dolai ◽  
Abhishake Mondal ◽  
Jun-Liang Liu ◽  
Mahammad Ali

Single crystal X-ray diffraction studies reveal that complexes 1 and 2 have square pyramidal geometry and 3 has octahedral geometry, which showed a dependence of negative anisotropy (D) values on the electronic, geometry and packing effects.


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