No abstract

N-salicylidene)-hydrazide (HL) was synthesised from the condensation of cinnamic acid hydrazide with salicylaldehyde and it was utilised as a fluorescent and colorimetric sensor for dual detection of Zn(II) and Al(III) ions. The solid-state structure of the ligand (HL) was stabilised by two-dimensional supramolecular network as evident from single crystal X-ray diffraction data. In solution the probe was found to have greater relative binding affinity and sensitivity towards Al(III) ion over Zn(II) ion. While the probe demonstrated very fast colorimetric response towards Zn(II) ion in solid state, it had superior fluorimetric sensitivity to Al(III) ion in solution by exhibiting distinct spectral changes. This unique phase dependent property of the probe has been exploited to easily detect Al(III) and Zn(II) ions. The above mentioned metal ions formed 2 : 1 (L : M) complexes with the probe which was supported by absorption and emission titration studies, Job's Plot and ESI mass spectral analysis. Most of the experimental outcomes were well supported by theoretical calculations.

Herein, we have reported three new Co(iii) complexes involving azo-appended Schiff base ligands.

Two mononuclear oxidovanadium(V) complexes type of [V V O(L 1 )(OMe)(MeOH)] ( 1 ), [V V O(L 2 )(OMe)(MeOH)] ( 2 ) and two [V 2 O 3 ] 4+ core of μ-oxidodioxidodivanadium(V) complexes (L 1 )(O)V V –O–V V (O)(L 1 ) ( 3 ) and (L 2 )(O)V V –O–V V (O)(L 2 ) ( 4 ) and two complexes [V V O(L 1 )(8-Hq)] ( 5 ) and [V V O(L 2 )(8-Hq)] ( 6 ) incorporating 8-hydroxyquinoline (8-hq) as co-ligand have been reported where L 1 [( E )- N ′-(2-hydroxybenzylidene)cinnamohydrazide] and L 2 [(2 E , N ′ E )- N ′-(2-hydroxybenzylidene)-3-(naphthalen-1-yl)acrylohydrazide] are the dianionic forms of the conjugated keto-imine functionalized substituted hydrazone ligands. The μ-oxidodioxidodivanadium complexes are generated upon switching the solvent from methanol to acetonitrile. The X-ray analysis showed octahedral geometry for the mononuclear complexes 1 , 2 and 5 but oxido-bridged dinuclear complexes 3 and 4 formed penta-coordinated square-pyramidal geometry about metal atoms. Two mixed-valence species of type II, 3a and 4a, of general formulae (L)(O)V IV –O–V V (O)(L), are being generated upon constant potential electrolysis (CPE) of 3 and 4 respectively. Frozen solution EPR spectra have 13 hyperfine lines, revealing the unpaired electron is majorly localized on one of the two vanadium centres. All these complexes have been well characterized by physio-chemical techniques and the density functional theory (DFT) calculations were applied to obtain further insight into the electronic structure of this type of molecule. The oxidomethoxido complexes 1 and 2 were taken to investigate the catechol oxidase mimicking activity following the oxidation of 3,5-di- tert -butyl catechol (3,5-DTBC) to 3,5-di- tert -butyl benzoquinone (3,5-DTBQ).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.