Pentamethylcyclopentadienyl M(III) Complexes (M = Rh, Ir) Exhibiting 2,3,5,6‐tetra(2'‐pyridyl)pyrazine as Seven‐membered Chelating Ligand

A novel Schiff base containing nitrogen-oxygen-sulfur (NOS) donor atoms formed from the condensation reaction of S-2,4-dichlorobenzyldithiocarbazate (S-2,4BDTC) with 5-fluroisatin has been synthesized. Complexes of cobalt(II), nickel(II), copper(II), zinc(II) and cadmium(II) with this Schiff base have been prepared and characterized using elemental analysis and various physico-chemical techniques. In the cobalt(II) and nickel(II) complexes the Schiff base behaves as a uninegatively charged tridentate nitrogen-oxygen-sulfur (NOS) chelating ligand, bonding through the azomethine nitrogen, thiolate sulfur and carbonylic oxygen of the isatin moiety. However, in the copper(II), zinc(II) and cadmium(II) complexes the Schiff base behaves as a nitrogen-sulfur (NS) bidentate chelating ligand, bonding through the azomethine nitrogen and thiolate sulfur. The Schiff base and the metal complexes were evaluated with respect to antimicrobial activity, which was performed in relation to two selected pathogenic microbials (Bacillus subtilis and Pseudomonas aeruginosa). It was observed that only the zinc Schiff base complex exhibited strong activity against the Bacillus subtilis bacteria with an inhibition zone of 25 mm.

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Synthesis, Characterization and Biological Activity of NitrogenOxygen-Sulfur (NOS) Transition Metal Complexes Derived from Novel S-2,4-dichlorobenzyldithiocarbazate with 5-fluoroisatin

Scientific Research Journal ◽

10.24191/srj.v7i2.5027 ◽

2010 ◽

Vol 7 (2) ◽

pp. 67

Author(s):

Mohd Abdul Fatah Abdul Manan ◽

Hadariah Bahron ◽

Karimah Kassim ◽

Mohd Asrul Hafiz Muhamad ◽

Syed Nazmi Sayed Mohamad

Keyword(s):

Bacillus Subtilis ◽

Schiff Base ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Condensation Reaction ◽

Inhibition Zone ◽

Azomethine Nitrogen ◽

Strong Activity ◽

Chelating Ligand ◽

Physico Chemical

A novel Schiff base containing nitrogen-oxygen-sulfur (NOS) donor atoms formed from the condensation reaction of S-2,4- dichlorobenzyldithiocarbazate (S-2.4BDTC) with 5-fluroisatin has been synthesized. Complexes of cobalt(ll), nickel(ll), copper(ll), zinc(ll) and cadmium(ll) with this Schiff base have been prepared and characterized using elemental analysis and various physico-chemical techniques. In the cobalt(ll) and nickel(II) complexes the SchifJbase behaves as a uninegatively charged tridentate nitrogen-oxygen-sulfur (NOS) chelating ligand, bonding through the azomethine nitrogen, thiolate sulfur and carbonylic oxygen of the isatin moiety. However. in the copper(ll), zinc(II) and cadmium(II) complexes the Schiff base behaves as a nitrogen-sulfur (NS) bidentate chelating ligand, bonding through the azomethine nitrogen and thiolate sulfur. The Schiff base and the metal complexes were evaluated with respect to antimicrobial activity, which was performed in reallion to two selected pathogenic microbials (Bacillus subtilis and Pseudomonas aeruginosa). It was observed that only the zinc Schiffbase complex exhibited strong activity against the Bacillus subtilis bacteria with an inhibition zone of25 mm.

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Nickel(II)-Methyl Complexes Adopting Idealized Seesaw Geometries

10.26434/chemrxiv.11288675.v1 ◽

2019 ◽

Author(s):

Ethan A. Hill ◽

Norman Zhao ◽

Alexander S. Filatov ◽

John Anderson

Keyword(s):

Singlet State ◽

Strong Field ◽

Structural Distortion ◽

Computational Results ◽

Threefold Symmetry ◽

Chelating Ligand ◽

Electronic Stabilization

We report four-coordinate nickel(II)-methyl complexes of tris-carbene borate ligands which adopt rare seesaw geometries. Experimental and computational results suggest the structural distortion from threefold symmetry results from a combination of electronic stabilization of the singlet state, strong field donors, and constrained angles from the chelating ligand.

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Synthesis, Characterization, and Electrochemical Behaviour of Cobalt(II) and Nickel(II) Complexes with N2O2 Chelating Ligand 4,4′-(Biphenyl-4,4′-diyldinitrilo)dipentan-2-one

Journal of Inorganic Chemistry ◽

10.1155/2013/104979 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Lakhdar Sibous ◽

Embarek Bentouhami ◽

Mustayeen Ahmed Khan

Keyword(s):

Schiff Base ◽

Mass Spectroscopy ◽

Elemental Analysis ◽

Electrochemical Behaviour ◽

Absolute Ethanol ◽

Molar Ratio ◽

H Nmr ◽

Chelating Ligand ◽

Metal Ligand

4,4′-Diaminobiphenyl reacts with 2,4-pentanedione in absolute ethanol in a molar ratio 1 : 2 to form mainly the product of [1 + 2] condensation, 4,4′-(biphenyl-4,4′-diyldinitrilo)dipentan-2-one (H2L). The Schiff base was used as tetradentate chelating ligand to coordinate CoII and NiII chlorides leading to complexes where the ratio of metal ligand was found to be 2 : 1 or 2 : 2. All the synthesized products were characterized by elemental analysis, infrared, electronic, and mass spectroscopy, 1H NMR, and DSC. The electrochemical behaviour of the ligand and its complexes in DMF is also investigated.

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