Phenylazophenol-quinone phenylhydrazone tautomerism in chromogenic cryptands and corands with inward-facing phenolic units and their acyclic analogs

Chromo and Fluorogenic Properties of Some Azo-Phenol Derivatives and Recognition of Hg2+ Ion in Aqueous Medium by Enhanced Fluorescence

“…Ltd.). To measure the pH of the azo-phenol derivatives 2 , 5 , and 6 , two methods have been adopted as reported previously …”

“…Therefore, development of a sensitive, reliable, concurrent, cost-effective, and aqueous medium compatible optical systems are in high demand for the detection of heavy and transition metal ions, particularly for the mercury ion contamination in water and the environment. In this prospective some specific chemosensors based on organic molecular systems/materials have been developed for the detection of Hg 2+ /Cu 2+ metal ions, to include, azo-derivatives, N -dansylcarbaxamide, aminonaphthol, anthrylacetamide, crown-ethers, thiocarbamate, naphthalimides, rhodamine, anthraquinone, benzothiazole, fluorescein, etc.…”

Effect of Interchromophoric Stacking Interactions on the Stability of the Sandwich-Type Complexes of 1-Hydroxy-9,10-anthraquinone-9-iminobenzo-15-crown-5 ether with Metal Cations

“…[5][6][7] Редким классом ОМС являются таутомерные хро-моионофоры. [8][9][10][11][12] Катион-индуцированные изменения в спектрах поглощения этих соединений обусловлены сдвигом таутомерного равновесия. Как правило, под этим равновесием подразумевается прототропная тау-томерия, т. е. обратимый перенос протона между двумя гетероатомами.…”

Rearrangements of Hydrazo, Azoxy and Azo Compounds: Kinetic, Product and Isotope Studies

“…Also studied have been azo-hydrazone tautomerism in [(arylazo)phenoxy]acetic acids and their organotin complexes 117 phenylhydrazone tautomerism in some cryptands and corands 118 , and the azo-hydrazo tautomerism and cis-trans isomerism that take place when 2-carboxy-2 -hydroxy-4 -methylazobenzenes are photolyzed 119 . AM1 theoretical calculations on a number of donor-acceptor azobenzenes agree reasonably well with experiment, and suggest that the energy differences between azo and hydrazone forms are quite small in a number of cases, although the azo form is usually more stable 120 .…”