Novel 4-Chloro-2-[(1-phenyl-1H-tetrazol-5-ylimino)-methyl] phenol (Cl-PTMP) and its transition metal complexes were synthesized and characterized by FT-IR, 1H-NMR, UV-Vis spectroscopy, Mass spectrometry, TGA and SEM. ...Novel 4-Chloro-2-[(1-phenyl-1H-tetrazol-5-ylimino)-methyl] phenol (Cl-PTMP) and its transition metal complexes were synthesized and characterized by FT-IR, 1H-NMR, UV-Vis spectroscopy, Mass spectrometry, TGA and SEM. The pH-metric technique was applied to get an insight of the number of dissociable protons and protonation sites in candidate compound. The pH-Metric studies were also carried out in presence of metal ions to establish the formation of corresponding metal complexes in solution. Further, the metal ligand compositions of Cu (II) and Co (II) complexes were determined spectrophotometrically by employing Job’s continuous variation method. To know the molecular properties in title imine compound suitable for metal ion coordination, the computational studies were carried out by employing HyperChem 7.5 tools. The energies of HOMO and LUMO frontier orbitals and their electron density contour maps were generated with geometry optimized molecule. Biological activity of Cl-PTMP and its metal complexes was investigated by disc diffusion method.展开更多
The coordination compounds of PdII, PtII, RhIII and IrIII metal ions with a Schiff base ligand (L) i.e. 2,6- diacetylpyridine bis(thiosemicarbazone) have been synthesized and characterized by elemental analyses, molar...The coordination compounds of PdII, PtII, RhIII and IrIII metal ions with a Schiff base ligand (L) i.e. 2,6- diacetylpyridine bis(thiosemicarbazone) have been synthesized and characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, IR, NMR and electronic spectral studies. On the basis of molar conductance and elemental analyses the complexes were found to have composition [M(L)]Cl2 and [M’(L)Cl]Cl2, where M = Pd(II), Pt(II) and M’ = Rh(III), Ir(III). The spectral studies reveal that the complexes possess monomeric composition. Complexes of PdII and PtII were found to have four coordinated square planar geometry whereas the complexes of RhIII and IrIII posses six coordinated octahedral geometry. The ligand field parameters were calculated using various energy level diagrams. In vitro synthesized compounds and metal salts have been tested against some species of plant pathogenic fungi and bacteria in order to assess their antimicrobial properties.展开更多
Schiff<sup> </sup>base synthesis is usually acid catalyzed and it usually requires refluxing the mixture of aldehydes and amine in ethanolic solution. Synthesis and characterization of Schiff base ligands ...Schiff<sup> </sup>base synthesis is usually acid catalyzed and it usually requires refluxing the mixture of aldehydes and amine in ethanolic solution. Synthesis and characterization of Schiff base ligands derived from substituted amine and salicylaldehyde and their complexes (Cu<sup>2+</sup>, Co<sup>2+</sup>) are reported. The ligands and ligand-complexes were characterized by melting point, FTIR, CHN-elemental analysis and UV-Visible analysis. The UV-Visible and elemental analysis of complexes established (1:2) mole ratio (M:L). The stability constant and thermodynamic parameters (K, ΔG, ΔH, ΔS) were determined at different temperature (30 - 40)°C which established that the metal-complexes were very stable. The review describes the promising biological<sup> </sup>activities of Schiff base and their metal complexes.展开更多
Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） complexes of Schiff bases derived from the condensation of sulfaguanidine with 2,4-dihydroxy benzaldehyde （HL1）, 2-hydroxy-l-naphthaldehyde （HL2） and ...Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） complexes of Schiff bases derived from the condensation of sulfaguanidine with 2,4-dihydroxy benzaldehyde （HL1）, 2-hydroxy-l-naphthaldehyde （HL2） and salicylaldehyde （HL3） have been synthesized. The structures of the prepared metal complexes were proposed based on elemental analysis, molar conductance, thermal analysis （TGA, DSC and DTG）, magnetic susceptibility measurements and spectroscopic techniques （IR, UV-Vis, and ESR）. In all complexes, the ligand bonds to the metal ion through the azomethine nitrogen and a-hydroxy oxygen atoms. The structures of Pd（Ⅱ） complex 8 and Ru（Ⅲ） complex 9 were found to be polynuclear. Two kinds of stereochemical geometries; distorted tetrahedral and distorted square py- ramidal, have been realized for the Cu（Ⅱ） complexes based on the results of UV-Vis, magnetic susceptibility and ESR spectra whereas octahedral geometry was predicted for Co（Ⅱ）, Mn（Ⅱ） and Ru（Ⅲ） complexes. Ni（Ⅱ） com- plexes were predicted to be square planar and tetrahedral and Pd（Ⅱ） complexes were found to be square planar. The antimicrobial activity of the ligands and their metal complexes was also investigated against the gram-positive bac- teria Staphylococcus aures and Bacillus subtilis and gram-negative bacteria, Escherichia coli and Pesudomonas aeruginosa, by using the agar dilution method. Chloramphenicol was used as standard compound. The obtained data revealed that the metal complexes are more or less, active than the parent ligand and standard. The X-ray crys- tal structure of HL3 has been also reported.展开更多
The complex of Eu（IH） with 1-（6-hydroxy- 1-naphthyl）- 1,3-butanedione （HNBD） was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The...The complex of Eu（IH） with 1-（6-hydroxy- 1-naphthyl）- 1,3-butanedione （HNBD） was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The IR and UV-visible spectra showed that Eu（Ⅲ） ion was coordinated to the HNBD ligand. The fluorescence spectrum showed the presence of Eu^3＋ characteristic emission. The TG-DTA-DTG curves showed that the thermal decomposition of the anhydrous complex was a two-stage process and the final residue was Eu2O3. The thermal decomposition kinetic parameters of the complex were evaluated from TG-DTG data by using three kinds of integral methods （Coat-Redfem equation, Horowitz and Metzger equation, Madhusudanan-Krishnan-Ninan equation）. The kinetic parameters of the first stage are E^＊ = 164.02 kJ.moll, A = 1.31 × 10^15 s^-l, AS^＊= 42.27 J·K^-l·mol^-l, △H^＊ = 159.51 kJ·mol^-l, △G^＊= 136.54 kJ·mol^-l, and n = 3.1, those of the second stage are E^＊= 128.52 kJ·mol^-l, A = 1.44× 106 s^-1, △S^＊= - 136.89 J·K^-l·mol^-l, △H^＊ = 120.41 kJ·mol^-l, △G^＊= 283.85 kJ·mol^-l, and n = 1.1.展开更多
文摘Novel 4-Chloro-2-[(1-phenyl-1H-tetrazol-5-ylimino)-methyl] phenol (Cl-PTMP) and its transition metal complexes were synthesized and characterized by FT-IR, 1H-NMR, UV-Vis spectroscopy, Mass spectrometry, TGA and SEM. The pH-metric technique was applied to get an insight of the number of dissociable protons and protonation sites in candidate compound. The pH-Metric studies were also carried out in presence of metal ions to establish the formation of corresponding metal complexes in solution. Further, the metal ligand compositions of Cu (II) and Co (II) complexes were determined spectrophotometrically by employing Job’s continuous variation method. To know the molecular properties in title imine compound suitable for metal ion coordination, the computational studies were carried out by employing HyperChem 7.5 tools. The energies of HOMO and LUMO frontier orbitals and their electron density contour maps were generated with geometry optimized molecule. Biological activity of Cl-PTMP and its metal complexes was investigated by disc diffusion method.
文摘The coordination compounds of PdII, PtII, RhIII and IrIII metal ions with a Schiff base ligand (L) i.e. 2,6- diacetylpyridine bis(thiosemicarbazone) have been synthesized and characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, IR, NMR and electronic spectral studies. On the basis of molar conductance and elemental analyses the complexes were found to have composition [M(L)]Cl2 and [M’(L)Cl]Cl2, where M = Pd(II), Pt(II) and M’ = Rh(III), Ir(III). The spectral studies reveal that the complexes possess monomeric composition. Complexes of PdII and PtII were found to have four coordinated square planar geometry whereas the complexes of RhIII and IrIII posses six coordinated octahedral geometry. The ligand field parameters were calculated using various energy level diagrams. In vitro synthesized compounds and metal salts have been tested against some species of plant pathogenic fungi and bacteria in order to assess their antimicrobial properties.
文摘Schiff<sup> </sup>base synthesis is usually acid catalyzed and it usually requires refluxing the mixture of aldehydes and amine in ethanolic solution. Synthesis and characterization of Schiff base ligands derived from substituted amine and salicylaldehyde and their complexes (Cu<sup>2+</sup>, Co<sup>2+</sup>) are reported. The ligands and ligand-complexes were characterized by melting point, FTIR, CHN-elemental analysis and UV-Visible analysis. The UV-Visible and elemental analysis of complexes established (1:2) mole ratio (M:L). The stability constant and thermodynamic parameters (K, ΔG, ΔH, ΔS) were determined at different temperature (30 - 40)°C which established that the metal-complexes were very stable. The review describes the promising biological<sup> </sup>activities of Schiff base and their metal complexes.
文摘Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） complexes of Schiff bases derived from the condensation of sulfaguanidine with 2,4-dihydroxy benzaldehyde （HL1）, 2-hydroxy-l-naphthaldehyde （HL2） and salicylaldehyde （HL3） have been synthesized. The structures of the prepared metal complexes were proposed based on elemental analysis, molar conductance, thermal analysis （TGA, DSC and DTG）, magnetic susceptibility measurements and spectroscopic techniques （IR, UV-Vis, and ESR）. In all complexes, the ligand bonds to the metal ion through the azomethine nitrogen and a-hydroxy oxygen atoms. The structures of Pd（Ⅱ） complex 8 and Ru（Ⅲ） complex 9 were found to be polynuclear. Two kinds of stereochemical geometries; distorted tetrahedral and distorted square py- ramidal, have been realized for the Cu（Ⅱ） complexes based on the results of UV-Vis, magnetic susceptibility and ESR spectra whereas octahedral geometry was predicted for Co（Ⅱ）, Mn（Ⅱ） and Ru（Ⅲ） complexes. Ni（Ⅱ） com- plexes were predicted to be square planar and tetrahedral and Pd（Ⅱ） complexes were found to be square planar. The antimicrobial activity of the ligands and their metal complexes was also investigated against the gram-positive bac- teria Staphylococcus aures and Bacillus subtilis and gram-negative bacteria, Escherichia coli and Pesudomonas aeruginosa, by using the agar dilution method. Chloramphenicol was used as standard compound. The obtained data revealed that the metal complexes are more or less, active than the parent ligand and standard. The X-ray crys- tal structure of HL3 has been also reported.
基金financially supported by the Important Foundation of the Educational Commission of Hubei Province (No. Z200622001)the Natural Science Foundation of the Educational Commission of Hubei Province, China (No. J200522002)
文摘The complex of Eu（IH） with 1-（6-hydroxy- 1-naphthyl）- 1,3-butanedione （HNBD） was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The IR and UV-visible spectra showed that Eu（Ⅲ） ion was coordinated to the HNBD ligand. The fluorescence spectrum showed the presence of Eu^3＋ characteristic emission. The TG-DTA-DTG curves showed that the thermal decomposition of the anhydrous complex was a two-stage process and the final residue was Eu2O3. The thermal decomposition kinetic parameters of the complex were evaluated from TG-DTG data by using three kinds of integral methods （Coat-Redfem equation, Horowitz and Metzger equation, Madhusudanan-Krishnan-Ninan equation）. The kinetic parameters of the first stage are E^＊ = 164.02 kJ.moll, A = 1.31 × 10^15 s^-l, AS^＊= 42.27 J·K^-l·mol^-l, △H^＊ = 159.51 kJ·mol^-l, △G^＊= 136.54 kJ·mol^-l, and n = 3.1, those of the second stage are E^＊= 128.52 kJ·mol^-l, A = 1.44× 106 s^-1, △S^＊= - 136.89 J·K^-l·mol^-l, △H^＊ = 120.41 kJ·mol^-l, △G^＊= 283.85 kJ·mol^-l, and n = 1.1.
