Basavaraj R. Patil

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.

Transition metal complexes of 3-aryl-2-substituted 1,2-dihydroquinazolin-4(3H)-one derivatives: new class of analgesic and anti-inflammatory agents.

Five-coordinate, neutral transition metal complexes of newly designed pyridine-2-ethyl-(3-carboxylideneamino)-3-(2-phenyl)-1,2-dihydroquinazolin-4(3H)-one (L) were synthesized and characterized. The structure of ligand is confirmed by single crystal X-ray diffraction studies. The compounds were evaluated for the anti-inflammatory activity by carrageenan-induced rat paw edema model while their analgesic activity was determined by acetic acid-induced writhing test in mice wherein the transition metal complexes were found to be more active than the free ligand.

Spectroscopic, magnetic and thermal studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes of 3-acetylcoumarin–isonicotinoylhydrazone and their antimicrobial and anti-tubercular activity evaluation

Co(II), Ni(II), Cu(II) and Zn(II) complexes with a new heterocyclic Schiff base derived by the condensation of isonicotinoylhydrazide and 3-acetylcoumarin have been synthesized. ¹H, ¹³C and 2D HETCOR NMR analyses confirm the formation of title compound and existence of the same in two isomeric forms. The metal complexes were characterized on the basis of various spectroscopic techniques like electronic, EPR, IR, ¹H and ¹³C NMR studies, elemental analysis, magnetic properties and thermogravimetric analysis, and also by the aid of molar conductivity measurements. It is found that the Schiff base behaves as a monobasic tridentate ligand coordinating in the imidol form with 1:1 metal to ligand stoichiometry. Trigonal bipyramidal geometry has been assigned for Ni(II) and Cu(II) complexes, while tetrahedral for Co(II) and Zn(II) complexes. The compounds were subjected to antimicrobial and anti-tubercular activity screening using serial broth dilution method and Minimum Inhibitory Concentration (MIC) is determined. Zn(II) complex has shown significant antifungal activity with an MIC of 6.25 μg/mL while Cu(II) complex is noticeable for antibacterial activity at the same concentration. Anti-TB activity of the ligand has enhanced on complexation with Co(II) and Ni(II) ions.

Antimicrobial Study of Newly Synthesized Lanthanide(III) Complexes of 2-[2-hydroxy-3-methoxyphenyl]-3-[2-hydroxy-3-methoxybenzylamino]-1,2-dihydroquinazolin-4(3H)-one.

New lanthanide(III) complexes with 2-[2-hydroxy-3-methoxyphenyl]-3-[hydroxyl-3-methoxybenzylamino]-1,2-dihydroquin- azoline-4(3H)-one (Hmpbaq) have been synthesized and characterized by elemental analysis, conductance measurements, magnetic susceptibilities, spectroscopic (IR, NMR, UV, EPR), and thermal studies. Molar conductance studies indicate 1 : 1 electrolytic behavior for these complexes. IR spectra indicate that Hmpbaq acts as a tridentate ligand coordinating through carbonyl oxygen, benzyl amine nitrogen, and deprotonated phenolic oxygen. TG and DTA studies of La(III) and Pr(III) complexes indicate the presence of two coordinated water molecules. Based on these studies, the complexes have been formulated as [La(mpbaq)2(H2O)2]·NO3, where Ln = La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Th(III), Dy(III), and Y(III). The ligand, lanthanide(III) salts, and the corresponding complexes have been simultaneously screened for their antibacterial and antifungal activities and compared with the drugs in use.

IR and Möessbauer studies of Sn(IV) complexes with branched tetradentates containing N and O donor centres

Abstract The branched tetradentate ligands prepared by condensing 2,2′-dihydroxychalkones with ethylenediamine are treated with anhydrous tin tetrachloride to yield the complexes of the type Sn · L · Cl2, where L is a doubly deprotonated ligand. The complexes are coloured yellow to greenish yellow. They are non-electrolytes. The IR data suggest the coordination of CN and NH2 groups to the Sn(IV) moiety and the involvement of both the OH groups in the reaction. The vSnO, vSnN and vSnCl vibrations have been assigned. The quadrupole splittings obtained for these complexes are small indicating cis-hexacoordinated Sn(IV) complexes. Considering the nature of the ligands and other spectral observations, we have proposed a polymetric structure for these complexes in which Sn has coordination number six.

Tin(IV) complexes with 2-methoxy-2′-hydroxy chalkones

Abstract Tin(IV) complexes with 2-methoxy-2′-hydroxy-5′-methyl and 2-methoxy-2′-hydroxy-5′-chloro chalkones have been prepared in benzene medium. The elemental analyses indicate Sn·L·Cl 3 stoichiometry (where LH is the ligand). They appear to be non-electrolytes in DMF. They are insoluble in most of the common organic solvents indiating the extended polymeric chain structure. The infrared spectral studies in the region 4000−200 cm −1 suggest that tin(IV) has coordination number six in these complexes.

Kupfer(II)-Komplexe mit monofunktionellen dreizähnigenSchiffbasen mit O,N,O-Sequenzen

A few complexes of copper(II) have been prepared by reacting copper(II) acetate with salicylidene methyl anthranilates in alcohol medium. Analytical data indicate 1 : 2 stoichiometry. These copper(II) complexes show normal magnetic moments indicating no spin interactions. With the help of electronic and infrared spectral evidences it has been suggested that in these complexes copper(II) exhibits coordination number six.

Kupfer(II)-Komplexe mit 2,2′-Dihydroxychalkonen

Copper(II) complexes with 2,2′-dihydroxychalkones have been prepared in aqueous alcohol medium and characterised by the elemental analysis. They have 1∶1 stoichiometry and i.r spectra show the involvement of the OH and C=O groups in the bond formation. These copper(II) complexes show magnetic moments in the range of 1.53–1.98 μB and are insoluble in common organic solvents. In view of the magnetic data, solubility and electronic spectral evidences, an extended polymeric structure has been proposed for these complexes.

Synthesis of novel tri-arm star shaped 1,3,5-triazine hydrazones from 2,4,6-tris(4-acetylphenoxy)-1,3,5-triazine core

A series of novel symmetric triazine hydrazones [N3C3(-OC6H4-p-C(CH3)=N-NH-C(O)-C6H4-p-X)3] (X = H, Br, Cl, F, OH, OCH3, CH3, NO2, NH2) were prepared in excellent yields by a three-fold condensation reaction of 2,4,6- tris(4-acetylphenoxy)-1,3,5-triazine with p-substituted benzoic acid hydrazides [NH2-NH-C(O)-C6H4-p-X]. The structures were confirmed by FT-IR, 1H, 13C, 2D-HMQC NMR and mass spectrometry (MALDI-TOF).

Cobalt(II) complexes ofSchiff bases derived from o-anisidine

A few complexes of cobalt(II) with monovalent tridentateSchiff bases have been prepared and characterised by elemental analysis. The magnetic, electronic and infrared spectral data show that cobalt(II) has coordination number six in these complexes.