Tuning of Spin Crossover Properties in a Series of Mononuclear Cobalt(II) Complexes Based on Macrocyclic Tetradentate Ligand and Pseudohalide Coligands

Author(s):  
Subrata Ghosh ◽  
S Selvamani ◽  
Sujit Kamilya ◽  
Sakshi Mehta ◽  
Abhishake Mondal

The three mononuclear cobalt(II) complexes, [Co(L)(NCX)2] (L = N,N'-di-tert-butyl-2,11-diaza[3,3](2,6)pyridinophane, and X = S (1), Se (2), and [C(CN)2] (3)), have been synthesized and characterized using variable temperature single-crystal X-ray crystallography,...

2020 ◽  
Vol 6 (3) ◽  
pp. 29
Author(s):  
Ryuta Ishikawa ◽  
Takeshi Noda ◽  
Shunya Ueno ◽  
Takashi Okubo ◽  
Hirofumi Yamakawa ◽  
...  

Herein, the syntheses, solid-state molecular structures, and characterization of two types of one-dimensional FeIII coordination polymers showing thermally induced spin crossover are reported. The reaction of [Fe(acen)Cl] (acen2− = N,N′-ethylenebis(acetylacetonylideneaminate) with 3,3′-bpy or 4,4′-bpy (bpy = bipyridine) produced zigzag and linear one-dimensional chain complexes, [Fe(acen)(3,3′-bpy)][BPh4] (1) or [NEt3H][Fe(acen)(4,4′-bpy)][BPh4]2·0.5(4,4′-bpy) (2), respectively, as confirmed by single crystal X-ray diffraction analysis. Variable-temperature single crystal X-ray diffraction measurements, continuous-wave X-band electron paramagnetic resonance (EPR) spectra, 57Fe Mössßauer spectra, and DC magnetic susceptibility data revealed that complex 1 exhibited a gradual and complete spin crossover at a transition temperature of 212 K, while complex 2 undergoes an incomplete spin crossover even at 400 K.


2021 ◽  
Vol 7 (5) ◽  
pp. 72
Author(s):  
Scott S. Turner ◽  
Joanna Daniell ◽  
Hiroki Akutsu ◽  
Peter N. Horton ◽  
Simon J. Coles ◽  
...  

Two novel salts containing the anion [Ni(mnt)2]− (mnt = maleonitriledithiolate) have been synthesized. The counter-ions, [Fe(II)(L1 or L2)2], are cationic complexes where L1 and L2 are methylated derivatives of 2,6-bis(pyazolyl)pyridine or pyrazine, which are similar to ligands found in a series of spin-crossover (SCO) complexes. Both salts are characterized by variable temperature single crystal X-ray diffraction and bulk magnetization measurements. Compound 1, [Fe(II)(L1)2][Ni(mnt)2]2 displays an incomplete and gradual SCO up to 300 K, followed by a more rapid increase in the high-spin fraction between 300 and 350 K. Compound 2, [Fe(II)(L2)2][Ni(mnt)2]2.MeNO2, shows a gradual, but more complete SCO response centered at 250 K. For compound 2, the SCO is confirmed by variable temperature Mössbauer spectroscopy. In both cases, the anionic moieties are isolated from each other and so no electrical conductivity is observed.


2021 ◽  
Author(s):  
Qi Zhao ◽  
Jin-Peng Xue ◽  
Zhi-Kun Liu ◽  
Zi-Shuo Yao ◽  
Jun Tao

A mononuclear complex with long alkyl chains, [FeII(H2Bpz2)2(C9bpy)] (1; H2Bpz2 = dihydrobis(1-pyrazolyl)borate, C9bpy = 4,4'-dinonyl-2,2'-bipyridine), was synthesized. Single-crystal X-ray crystallographic studies revealed that - and - forms of the complex...


1983 ◽  
Vol 38 (4) ◽  
pp. 426-427 ◽  
Author(s):  
Arndt Simon ◽  
Karl Peters ◽  
Harry Hahn

Abstract The structure of the title compound has been determined by X-ray crystallography. The title compound is synthesized from the elements at 600 °C. Its crystal structure, derived from powder data [3] is refined by single crystal diffractometer data. The structure is trigonal (P3̅ml, α = 684.1(1), c = 724.4(1) pm); Pd2+ cations and PS43- anions form a network with an anti-Claudetite (AS2O3) type structure. The PS4 units are distinctly distorted from ideal tetrahedral symmetry. The Pd atoms have a planar environment of 4 S atoms.


2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Stergios Zanias ◽  
Giannis S. Papaefstathiou ◽  
Catherine P. Raptopoulou ◽  
Konstantinos T. Papazisis ◽  
Vasiliki Vala ◽  
...  

As part of our interest into the bioinorganic chemistry of gallium, gallium(III) complexes of the azole ligands 2,1,3-benzothiadiazole (btd), 1,2,3-benzotriazole (btaH), and 1-methyl-4,5-diphenylimidazole (L) have been isolated. Reaction of btaH or btd withGaBr3orGaCl3resulted in the mononuclear complexes[GaBr3(btaH)2](1) and[GaCl3(btd)2](2), respectively, while treatment ofGaCl3with L resulted in the anionic complex(LH)2[GaCl4](3). All three complexes were characterized by single-crystal X-ray crystallography and IR spectroscopy, while their antiproliferative activities were investigated against a series of human and mouse cancer cell lines.


2012 ◽  
Vol 16 (01) ◽  
pp. 154-162 ◽  
Author(s):  
Edwin W.Y. Wong ◽  
Daniel B. Leznoff

The reduction of magnesium phthalocyanine (MgPc) with 2.2 equivalents of potassium graphite in 1,2-dimethoxyethane (DME) gives [K2(DME)4]PcMg(OH)(1) in 67% yield. Compound 1 was structurally characterized using single crystal X-ray crystallography and was found to be a monomeric, heterometallic complex consisting of a μ3-OH ligand that bridges a [MgIIPc3-]- anion to two potassium cations solvated by four DME molecules. An absorption spectrum of 1 confirms the Pc ligand is singly reduced and has a 3–charge. The solid-state structure of 1 does not indicate breaking of the aromaticity of the Pc ligand. Compound 1 is only the second Pc3- complex and the first reduced MgPc to be isolated and structurally characterized.


2002 ◽  
Vol 57 (9) ◽  
pp. 1017-1026 ◽  
Author(s):  
Herbert Schumann ◽  
Susanne Stenz ◽  
Frank Girgsdies ◽  
Stefan H. Mühle

Ru3(CO)12 reacts with 1-tert-butyl-2,4-cyclopentadiene (1), 1-trimethylsilyl-2,4-cyclopentadiene (2), 1-tert-butyl-3-methyl-2,4-cyclopentadiene (3), 1,3-di(tert-butyl)-2,4-cyclopentadiene (4), 1-iso-propyl-2,3,4,5-tetramethyl-2,4-cyclopentadiene (5), 1-tert-butyl-2,3,4,5-tetramethyl- 2,4-cyclopentadiene (6), 1-phenyl-2,3,4,5-tetramethyl-2,4-cyclopentadiene (7), 2,5- diphenyl-2,4-cyclopentadiene (8), or 2,3,4,5-tetraphenyl-2,4-cyclopentadiene (9) with formation of the corresponding bis[dicarbonyl(cyclopentadienyl) ruthenium(I)] complexes [RuCp# (CO)2]2 1a to 9a. The 1H and 13C NMR spectra of the new compounds 3a and 5a to 9a as well as the single crystal X-ray structures of 1a, 4a, 5a, 7a, 8a, and 9a are reported and discussed


Crystals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 113
Author(s):  
Younes Hanifehpour ◽  
Babak Mirtamizdoust ◽  
Jaber Dadashi ◽  
Ruiyao Wang ◽  
Mahboube Rezaei ◽  
...  

A novel Bi (III) coordination compound, [Bi(HQ)(Cl)4]n ((Q = pyridine-4-carbaldehyde thiosemicarbazone), was prepared in this research using a sonochemical technique. SEM, infrared spectroscopy (IR), XRD, and single-crystal X-ray analysis were utilized to analyze the Bi(III) coordination compound. The structure determined using single-crystal X-ray crystallography indicates that the coordination compound is a 1D polymer in solid state and that the coordination number of bismuth (III) ions is six, (BiSCl5), with one S donor from the organic ligand and five Cl donors from anions. It is equipped with a hemidirectional coordination sphere. It is interesting that the ligand has been protonated in the course of the reaction with a Cl- ion balancing the charge. This compound’s supramolecular properties are directed and regulated by weak directional intermolecular interactions. Through π–π stacking interactions, the chains interact with one another, forming a 3D framework. Thermolysis of the compound at 170 °C with oleic acid resulted in the formation of pure phase nanosized Bi (III) oxide. SEM technique was used to examine the morphology and size of the bismuth (III) oxide product produced.


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