scholarly journals Synthesis, characterization and spectroscopic studies of the dihydrobis(1,2,3-benzotriazolyl)borate anion and its complexes with MCl2·py2

2006 ◽  
Vol 71 (11) ◽  
pp. 1137-1145 ◽  
Author(s):  
Khwaja Siddiqi ◽  
Ahmad Umar ◽  
Shahab Nami ◽  
Sadaf Khan
Keyword(s):  
Sodium Borohydride ◽  
Elemental Analysis ◽  
Spectroscopic Studies ◽  
Molar Conductance ◽  
Ligand Field ◽  
Conductivity Measurements ◽  
Ligand Field Parameters

The preparation of sodium dihydrobis(1,2,3-benzotriazolyl)borate was realised by refluxing one mole of sodium borohydride with two moles of 1,2,3-benzotriazole in toluene over a period of 12 h. Its complexes with MCl2?py2 [where M= Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and py = Pyridine] were characterized by elemental analysis as well as magnetic, spectroscopic and conductivity measurements. On the basis of these studies, it is proposed that the geometry of all the complexes is octahedral. The ligand field parameters 10 Dq, B and ? show extensive overlap between the M-L orbital. The molar conductance of 10-3Msolutions of the complexes in DMSO suggest them to be non-ionic in nature.

scholarly journals Spectroscopic studies of benzoxazole-2-thione complexes. Derivatives of cobalt(II) and nickel(II) halides

1976 ◽  
Vol 54 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Carlo Preti ◽  
Giuseppe Tosi
Keyword(s):  
Magnetic Susceptibility ◽  
Ir Spectra ◽  
Electronic Spectra ◽  
Spectroscopic Studies ◽  
Ligand Field ◽  
Conductivity Measurements ◽  
Derivatives Of ◽  
Ligand Field Parameters ◽  
Cobalt And Nickel

The preparation of some complexes of benzoxazole-2-thione with halides of cobalt(II) and nickel(II) is reported. The complexes of cobalt(II) and nickel(II) are tetrahedral of the type ML2X2 with the exception of NiLBr2. The complexes have been studied by means of magnetic susceptibility measurements, infrared and far ir spectra, electronic spectra, and conductivity measurements. The ligand behaves as monodentate N-bonded. The various ligand field parameters, Dq, B′, and β show about 60 and 80% of covalency in the cobalt(II) and nickel(II) complexes respectively and suggest a medium strong ligand field. The spectroscopy parameters of cobalt and nickel derivatives confirm the presence of CoN2X2 and NiN2X2 chromophores.

N,N′-Bis(phenylaminomethyl)parabanic add as a complexing agent. Complexes of some bivalent first row transition metals

1977 ◽  
Vol 55 (2) ◽  
pp. 344-349 ◽  
Author(s):  
Antonio Costantino Fabretti ◽  
Gian Carlo Franchini ◽  
Carlo Preti ◽  
Giuseppe Tosi
Keyword(s):  
Nmr Spectra ◽  
Far Infrared ◽  
Complexing Agent ◽  
Ligand Field ◽  
Conductivity Measurements ◽  
B Values ◽  
Nitrogen Bonds ◽  
Ligand Field Parameters ◽  
Far Infrared Spectra ◽  
Metal Ligand

The preparation of some complexes of N,N′-bis(phenylaminomethyl)parabanic acid with halides of cobalt(II), nickel(II), and copper(II) is reported. The complexes of the type MLX2 seem to have pseudo-tetrahedral and pseudo-octahedral symmetry. The complexes have been studied by means of magnetic susceptibility measurements, infrared and far infrared spectra, electronic and nmr spectra, and conductivity measurements. The ligand behaves as bidentate N-bonded. The various ligand field parameters, Dq, B', and β have been evaluated. The B' values suggest a strong covalency in the metal–ligand σ bond and Dq values show a medium strong ligand field. The presence of metal–nitrogen bonds is suggested. The possible stereochemistries of the complexes are discussed in the light of the experimental results.

scholarly journals Synthesis, Spectral, Magnetic and Thermal Studies of the Complexes of CoIIand NiIIWith Some Bidentate and Tridentate Hydrazone Ligands

2005 ◽  
Vol 2 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Chetan K. Modi ◽  
Ashwin S. Patel ◽  
Bharat T. Thaker
Keyword(s):  
Magnetic Moments ◽  
Picolinic Acid ◽  
Thermal Studies ◽  
Acid Hydrazide ◽  
Spectral Studies ◽  
Ligand Field ◽  
Conductivity Measurements ◽  
Octahedral Structure ◽  
Hydrazone Ligands ◽  
Ligand Field Parameters

The reaction of Co(NO3)2.6H2O and Ni(NO3)2.6H2O with hydrazones derived from 1-phenyl-3-methyl-4-acyl-5-pyrazolone (where acyl = acetyl, propionyl, butyryl and benzoyl) with 2-picolinic acid hydrazide have been studied and characterized on the basis of elemental analysis, magnetic moments, molar conductivity measurements, IR and electronic spectral studies and thermogravimetric analysis. Various ligand field parameters have been calculated. Electronic spectral data and the magnetic moment values suggest an octahedral structure for all cobalt(II) and nickel(II) complexes.

scholarly journals Biological Active Cobalt(II) and Nickel(II) Complexes of 12-Membered Hexaaza [N6] Macrocyclic Ligand Synthetic and Spectroscopic Aspects

2010 ◽  
Vol 7 (4) ◽  
pp. 1238-1245 ◽  
Author(s):  
Umendra Kumar ◽  
Sulekh Chandra
Keyword(s):  
Thermal Analysis ◽  
Magnetic Susceptibility ◽  
Metal Ion ◽  
Macrocyclic Ligand ◽  
Pathogenic Fungi ◽  
Spectroscopic Studies ◽  
Molar Conductance ◽  
Octahedral Geometry ◽  
Conductivity Measurements ◽  
Macrocyclic Schiff Base

New cobalt(II) and nickel(II) complexes of 12-membered macrocyclic Schiff - base ligand containing thiosemicarbazone moiety as a part of ring have been prepared having general composition [MLX2] where M = Co(II) or Ni(II), L=3,4,9,10–tetra-2-furanyl-1,2,5,6,8,11- hexaazacyclododeca-7,12- dithione - 2,4,8,10 – tetraene, X = Cl-, NO3-, NCS-. The complexes have been characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, spectral (IR, electronic, EPR) techniques and thermal analysis. Spectroscopic studies suggested a six coordinated octahedral geometry for all the complexes. The IR spectra of complexes suggest that ligand is coordinated to the metal ion through its four imines nitrogen. Conductivity measurements supported the non electrolytic nature of the complexes. The antifungal activities of complexes have been studied against a number of pathogenic fungi under laboratory conditions. The complexes showed good antifungal results. Thermal analysis of reported complexes suggests the absence of water molecule either in or outside the coordination sphere.

In vitro antifungal and antibacterial properties of thiodiamine transition metal complexes

2009 ◽  
Vol 63 (5) ◽  
Author(s):  
Ajay Mishra ◽  
Shivani Mishra ◽  
Narender Kaushik
Keyword(s):  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Elemental Analysis ◽  
Binding Sites ◽  
Antibacterial Properties ◽  
Spectroscopic Studies ◽  
Molar Conductance ◽  
Azomethine Nitrogen ◽  
Biological Studies

AbstractSynthesis, characterization and biological studies of some thiodiamine metal complexes are described. Cobalt(II) and copper(II) complexes of type [Cu(L)2Cl2] and [Co(L)2SO4], where L = (cyclohexyl-N-thio)-1,2-ethylenediamine (L1) and (cyclohexyl-N-thio)-1,3-propanediamine (L2), were synthesized. The synthesized copper and cobalt thiodiamine complexes were characterized by elemental analysis, IR, mass, UV-VIS and 1H NMR spectroscopic studies. Thiodiamines coordinate as a bidentate N-S ligand. The binding sites are azomethine nitrogen and thioamide sulfur. Molar conductance values in dimethylsulfoxide indicate non-electrolyte nature of the complexes. In vitro-antimicrobial screening shows promising results against both bacterial and fungal strains.

Some Organoperoxo Complexes of Tin(IV)

1997 ◽  
Vol 50 (3) ◽  
pp. 229 ◽  
Author(s):  
M. Tofazzal H. Tarafder ◽  
Wan M. Z. W. Yunus ◽  
Sidik Silong
Keyword(s):  
Elemental Analysis ◽  
Oxygen Transfer ◽  
Oxidative Addition ◽  
Spectroscopic Studies ◽  
Triphenylphosphine Oxide ◽  
Kinetic Stability ◽  
Transfer Reactions ◽  
Conductivity Measurements ◽  
Infrared Spectroscopic

Some novel organoperoxo complexes of tin were prepared by the oxidative addition of dioxygen with Sn 2+. These are the first reported examples of this kind. The complexes isolated have the compositions [Sn(O2)2.2L], [Sn(O2)2L′], [Sn(O2)L′′2], [Sn(O2)C5H3N(COO)2H2O] and [Sn(O2)2L′′′] (L = pyridine, pyridine N-oxide, triphenylphosphine oxide, aniline; L′ = ethylenediamine, 2-aminopyridine, o-phenylenediamine; L′′ = pyridine-2-carboxylato, 2-aminophenolato, quinolin-8-olato, glycinato; L′′′ = diethylenetriamine and triethylenetetramine). The complexes were characterized by elemental analysis, conductivity measurements and infrared spectroscopic studies. None of these complexes showed oxygen transfer reactions. The ν1(O-O) stretching frequencies appear at 805-820 cm-1 , and are significantly insensitive to the choice of the coligands used. Extensive pp-dp bonding in the complexes renders absolute kinetic stability to the complexes.

The Coordination Chemistry of Phosphoryl Compounds Containing the — N(CH3)2 Group, Part VIII

1972 ◽  
Vol 27 (7) ◽  
pp. 759-763 ◽  
Author(s):  
M. W. G. De Bolster ◽  
W. L. Groeneveld
Keyword(s):  
Coordination Chemistry ◽  
General Formula ◽  
Ligand Field ◽  
Chemical Analyses ◽  
X Ray ◽  
Physical Measurements ◽  
Ligand Field Spectra ◽  
Chloride Adduct ◽  
Ligand Field Parameters ◽  
Group Part

A number of new solvates and adducts containing bisphenyldimethylaminophosphine oxide is reported. The solvates have the general formula M[(C6H5)2P(O)N(CH3)2]42+(anion-)2, in which M = Mg, Ca, Mn, Fe, Co, Ni, Cu, Zn and Cd, and the anions are ClO4- and BF4-. The adducts have the general formula M[(C6H5)2P(O)N(CH3)2]2Cl2, where M stands for the same series of metals.The compounds are characterized and identified by chemical analyses and physical measurements.Ligand-field and vibrational spectra have been investigated; values for the ligand-field parameters are reported. It is concluded that coordination takes place via the oxygen atom of the ligand.X-ray powder patterns were used in combination with ligand-field spectra to deduce the coordination around the metal ions.The interesting behaviour of the nickel (II) chloride adduct upon heating is discussed and it is shown that both a square pyramidal and a tetrahedral modification exists.

Ligand Field Parameters

1976 ◽  
Vol 15 (3-4) ◽  
pp. 189-199 ◽  
Author(s):  
Ivano Bertini ◽  
Dante Gatteschi ◽  
Andrea Scozzafava
Keyword(s):  
Ligand Field ◽  
Ligand Field Parameters

scholarly journals Computational Studies of 4-Formylpyridinethiosemicarbazone and Structural and Biological Studies of Its Ni(II) and Cu(II) Complexes

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Mydhili P. Sripathi ◽  
Sireesha Berely ◽  
Chittireddy Venkata Ramana Reddy
Keyword(s):  
Elemental Analysis ◽  
Radical Scavenging ◽  
Molar Conductance ◽  
Computational Studies ◽  
Hydrolytic Cleavage ◽  
Bacterial Strains ◽  
Intercalative Mode ◽  
Biological Studies ◽  
Calf Thymus ◽  
The Stability

To understand the stability, chelation behaviour, and biological activity of 4-Formylpyridinethiosemicarbazone (H4FPT), it is important to recognize its interactive geometry. Hence, computational studies on geometrically optimized structures of thione and thiol forms of H4FPT were performed. Binary metal complexes of the ligand, H4FPT (L) with the Ni(II) and Cu(II) metal ions (M), were synthesized and characterized by various spectroanalytical techniques as elemental analysis, molar conductance, magnetic susceptibility measurements, LC-MS, TGA, IR, UV-Visible, ESR, and powder XRD. Elemental analysis, LC-MS, and TGA studies indicate 1:2 (ML2) composition for mononuclear Ni(II) complex and 1:1 (ML) composition for dinuclear Cu(II) complex. Electronic absorption titrations, fluorescence quenching studies, and viscosity measurements suggest intercalative mode of binding of the complexes with calf thymus DNA (CT-DNA). These complexes also promote hydrolytic cleavage of plasmid pBR322. The ligand (H4FPT) and its complexes showed moderate-to-good activity against Gram-positive and Gram-negative bacterial strains. The DPPH radical scavenging studies showed antioxidant nature of both complexes.

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