. "RIV/62690094:18470/13:50001336!RIV14-MSM-18470___" . "Mervat, Elsedik" . . . "Old\u0159ich, Machalick\u00FD" . "Ly\u010Dka, Anton\u00EDn" . . . "Synthesis and spectral properties of new hydrazone dyes and their Co(III) azo complexes"@en . . "3" . . . "Dyes and pigments" . . "98" . . "Synthesis and spectral properties of new hydrazone dyes and their Co(III) azo complexes" . . "1"^^ . "Stanislav, Lu\u0148\u00E1k" . "10.1016/j.dyepig.2013.04.012" . . "A series of six keto-hydrazone dyes was prepared by azo coupling of diazotised substituted 2- aminophenols with pyrrolinone esters. All keto-hydrazone compounds were found as a mixtures of E and Z isomers by 1H NMR. Irrespective to the position of nitro substituent on the phenol ring, all compounds fluoresce strongly only in solvent glass at 77 K except 4-nitro derivatives which also weakly fluoresce in solution and in solid-state at room temperature. Using these hydrazones as tridentate O-N-O\u00B4 ligands, six symmetrical 2:1 octahedral Co(III) complexes were prepared. Multinuclear NMR combined with 15N labelled hydrazone derivative proved that the starting mixture of hydrazone isomers was converted exclusively to E-azo configuration in complexes with coordinated nitrogen atoms coming solely from phenolic residues. The considerably different effect of 4- and 5-nitrophenol substituents on absorption spectra of the ligands and complexes was ascribed to prevailing azo character of an electronic structure of a ligand in the complex, based on TD DFT calculations."@en . "18470" . "6"^^ . "NL - Nizozemsko" . "Synthesis and spectral properties of new hydrazone dyes and their Co(III) azo complexes"@en . "Radim, Hrdina" . "000321169000031" . "[259E56E5B00A]" . . "10"^^ . "Synthesis and spectral properties of new hydrazone dyes and their Co(III) azo complexes" . "RIV/62690094:18470/13:50001336" . . . . "N, P(EE2.3.30.0021)" . . "109488" . . "Tarek, Aysha" . . . "DFT; fluorescence spectra; absorption spectra; metal-azo komplex; pyrrolinone; Hydrazone"@en . "0143-7208" . "A series of six keto-hydrazone dyes was prepared by azo coupling of diazotised substituted 2- aminophenols with pyrrolinone esters. All keto-hydrazone compounds were found as a mixtures of E and Z isomers by 1H NMR. Irrespective to the position of nitro substituent on the phenol ring, all compounds fluoresce strongly only in solvent glass at 77 K except 4-nitro derivatives which also weakly fluoresce in solution and in solid-state at room temperature. Using these hydrazones as tridentate O-N-O\u00B4 ligands, six symmetrical 2:1 octahedral Co(III) complexes were prepared. Multinuclear NMR combined with 15N labelled hydrazone derivative proved that the starting mixture of hydrazone isomers was converted exclusively to E-azo configuration in complexes with coordinated nitrogen atoms coming solely from phenolic residues. The considerably different effect of 4- and 5-nitrophenol substituents on absorption spectra of the ligands and complexes was ascribed to prevailing azo character of an electronic structure of a ligand in the complex, based on TD DFT calculations." .