77761-40-1Relevant articles and documents
Kinetics of photochemical reactions of a new biphotochromic compound upon photolysis with light of different wavelengths
Levin,Zaichenko,Tatikolov,Shienok,Kol’tsova,Shcherbakova,Os’kina, O. Yu.,Mardaleishvili,Ait,Berlin
, p. 259 - 265 (2016)
Using the method of microsecond flash photolysis with UV and visible light, the spectral and kinetic characteristics of intermediate products of photolysis in toluene and methanol solutions of a new biphotochromic compound have been studied, in which two photochromic moieties, spironaphthoxazine and azomethine, are linked to each other in such a way that there is conjugation between π-electronic systems of the moieties in the ground state of the molecule. Two intermediate products have detected, whose relative efficiency of formation substantially depends on the solvent and the wavelength of excitation light.
Substituent and solvent effects on the proton transfer equilibrium in anils and azo derivatives of naphthol. Multinuclear NMR study and theoretical calculations
Alarcón, Sergio H.,Olivieri, Alejandro C.,Sanz, Dionisia,Claramunt, Rosa M.,Elguero, José
, p. 1 - 9 (2007/10/03)
The tautomeric equilibrium due to proton transfer is compared in a series of anils of 2-hydroxynaphthalene-1-carbaldehyde and azo derivatives of 2-naphthol. Although structurally similar, these systems suffer different substituent effects on the solution-state proton transfer properties. The comparative study was performed using 1H, 13C and 15N NMR spectroscopy in a variety of solvents. Hartree-Fock ab initio calculations involving relative stability of tautomers and full geometry optimization for the ground state are in agreement with the experimental observations.
Tautomerism of 2-hydroxynaphthaldehyde Schiff bases
Antonov, Liudmil,Fabian, Walter M.F.,Nedeltcheva, Daniela,Kamounah, Fadhil S.
, p. 1173 - 1179 (2007/10/03)
A UV-Vis spectroscopic study based on the recently developed chemometric approach for quantitative analysis of undefined mixtures is performed on a series of donor and acceptor substituted Schiff bases of 2-hydroxynaphthaldehydes. In CCl4 solution all compounds preferentially exist as the phenol tautomer independent of the nature of the respective substituent. With increasing polarity the tautomeric equilibrium is shifted towards the quinone form. In CHCl3 and, especially, ethanol a clear distinction between the effect of donors (stabilization of the quinone form) and acceptors (stabilization of the phenol tautomer) is evident. Ab initio calculations including solvent effects via the polarized continuum model of solvation as well as the supermolecule approach are used to rationalize the experimental findings.
13C NMR Spectroscopic and AM1 Study of the Intramolecular Proton Transfer in Anils of Salicylaldehyde and 2-Hydroxynaphthalene-1-carbaldehyde
Alarcon, Sergio H.,Olivieri, Alejandro C.,Gonzales-Sierra, Manuel
, p. 1067 - 1070 (2007/10/02)
Tautomeric equilibria in intramolecularly hydrogen bonded Schiff bases is studied on the basis of solution 13C NMR chemical shifts.Variable temperature NMR spectroscopic data and comparison with appropriate models show that while anils of salicaldehyde exist as phenolic tautomers, those of 2-hydroxynaphthalene-1-carbaldehyde exist as equilibrium mixtures containing appreciable amounts of both enol and keto tautomers, the latter being slightly predominant.AM1 results concerning the relative stability of tautomers are in good agreement with the NMR spectroscopic information.
