N.S. Biradar

Dimeric square planar complexes of Cu(II) with aroyl hydrazones

Abstract Cu(II) complexes with aroyl hydrazones have been prepared in ethanol medium and characterised by elemental analysis. They have 1:1 stoichiometry. I. R. results show that the hydrazones exist in the enol form in the complexes. These Cu(II) complexes show subnormal magnetic moments and the electronic spectra agree with the square planar configuration. In view of the magnetic and electronic spectral evidence, the dimeric square planar configuration is suggested in which Cuue5f8Cu interaction exists.

Amino acid schiff base complexes of dimethyldichlorosilane

Abstract A few complexes of dimethyldichlorosilane with Schiff bases derived from the condensation of salicylaldehyde, benzaldehyde, pyridine-3-carboxyaldehyde and pyridine-4-carboxyaldehyde with glycine and α-alanine were prepared. The complexes were characterized by elemental analysis, conductivity measurements, infrared and proton magnetic resonance spectral data. Antibacterial activity data show that the silane complexes are better inhibitors than the corresponding free ligands.

Structural and biological studies on benzimidazolyl amino acid complexes of dimethyldichlorosilane

Abstract Several benzimidazolyl amino acid complexes of dimethyldichlorosilane are synthesized. The complexes were characterized by elemental analyses, conductivity measurements, infrared and proton magnetic resonance spectral data. The complexes are nonelectrolytes in DMF solution and exhibit 1:1 (metal:ligand) stoichiometry. Furthermore, the complexes are found to be biologically active as demonstrated by antibacterial and antiinflammatory tests.

Transformation of square-planar dsp2 configuration of Ni(II) aldoximates into octahedral sp3d2 configuration by reaction with tin(IV) chloride

Abstract Tin(IV) chloride derivatives of nickel(II) aldoximates have been obtained by reacting tin(IV) chloride with nickel(II) aldoximates in benzene. All the complexes are coloured solids and appear to be non-electrolytes in DMF. Elemental analyses agree with 1:1 stoichiometry. Magnetic, electronic and far i.r. spectral data suggest that the nickel(II) has changed its configuration from dsp2 square-planar to sp3d2 octahedral one as a result of reaction with the tin(IV) chloride. Tin(IV), also exhibits 6-coordination in these complexes.

TITANIUM(IV) COMPLEXES WITH TRIDENTATE SCHIFF BASES CONTAINING ONO SEQUENCES

Abstract Titanium(IV) chelates have been prepared by a novel method, reacting titanyl perchlorate with tridentate aromatic Schiff bases containing ONO sequences. The complexes are reddish brown microcrystalline substances and have 1:2 stoichiometry, TiL 2 , where H 2 L is a tridentate Schiff base. Infrared spectra in 4000–250 cm −1 region show the coordination through azomethine nitrogen and involment of the OH groups in bond formation. It is argued that the azomethine nitrogen atoms are occupying the axial positions of the octahedron. The electronic and pmr spectra of the complexes are also discussed.

BIOLOGICALLY ACTIVE SULFONAMIDE SCHIFF BASE COMPLEXES OF SELENIUM(IV) AND TELLURIUM(IV)

Abstract Several sulfonamide-Schiff base complexes of selenium(IV) and tellurium(IV) were prepared and characterized using conductivity measurements, and infrared and proton magnetic resonance spectra. Elemental analyses confirmed a 1:2 (metal:sulfonamide-Schiff base) stoichiometry. Most of the complexes proved to be biologically active as evidenced by pharmacological tests.

Synthesis and characterization of biologically active organosilicon and organotin complexes of phenylglycyl hydrazones

Abstract A few organosilicon and organotin complexes of phenylglycyl hydrazones were synthesized and characterized by elemental analyses, conductivity measurements, infrared and proton magnetic resonance spectral data. The complexes were found to be non- electrolytes in DMF solution and exhibit a 1:1 (metal:ligand) stoichiometry. Also, the complexes are biologically active as indicated by antibacterial testing.

Schiff-base complexes of dimethyldichlorosilane

Abstract Several Schiff-bases obtained by the condensation of monoamine or diamine with substituted benzaldehyde were synthesized and then coordinated with dimethyldichlorosilane. The products of reaction were characterized by elemental analyses, conductivity measurements, and infrared and nuclear magnetic resonance spectroscopic data. A majority of the complexes exhibit a 1:1 (silicon: Schiff-base) stoichiometry and a few have 1:2 stoichiometry.

Dioxouranium(VI) complexes with aldoximes

Abstract Dioxouranium(VI) complexes have been prepared by treating uranyl nitrate with aldoxime in aqueous alcohol medium (pH 8). The complexes are orange-yellow to yellow-brown in colour. These complexes are characterised by elemental analysis, conductometric and spectral data. The intermolecular hydrogen bonding present in the ligands is still retained in the complexes. Based on these results an octahedral structure may be proposed.

Spectral and magnetic studies of amino-acid schiff base complexes of nickel(II)

Abstract A variety of o-hydroxyacetophenone-glycine imines coordinated to nickel(II) have been synthesized. These complexes have been further characterized by conductivity measurements, magnetic data, electronic, infrared and nuclear magnetic resonance spectral data. The results suggest that the complexes are four coordinate with a square planar configuration. The ligands bind through the imino nitrogen and carboxylate groups.