In: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2020, vol. 237, p. 118416
The paper presents the synthesis and characterization of two 4-substituted phthalimide 2-hydroxy-Schiff bases containing salicylic (4) and 2-hydroxy-1-naphthyl (5) moieties. The structural differences of 2-hydroxyaryl substituents, resulting in different enol/keto tautomeric behaviour, depending on the solvent environment were studied by absorption UV–Vis spectroscopy. Compound 5 is...
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In: Molecules, 2020, vol. 25, no. 2, p. 298
Two novel pinene-type ligands have been synthesized and their tautomeric and self- associating behavior studied in solution and in the solid state. The first ligand, an acetylated derivative of 5,6-pinene-bipyridine, displays keto-enol tautomerism in solution. This tautomeric equilibrium was studied by NMR and UV-Vis spectroscopy in various solvents, and the results were compared with the ones...
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In: Beilstein Journal of Organic Chemistry, 2019, vol. 15, no. 1, p. 1898–1906
The concept for sensing systems using the tautomerism as elementary signaling process has been further developed by synthesizing a ligand containing 4- (phenyldiazenyl)naphthalene-1-ol as a tautomeric block and an amide group as metal capturing antenna. Although it has been expected that the intramolecular hydrogen bonding (between the tautomeric hydroxy group and the nitrogen atom from the...
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In: Dyes and Pigments, 2019, vol. 165, p. 157–163
In order to meet the need for NMR reference compounds in the study of tautomeric azo dyes, two series of azo dyes, derived from 3-methyl-1-phenyl-4- (phenyldiazenyl)-1H-pyrazol-5-amine and 5-methyl-2-phenyl-4-(2- phenylhydrazono)-2,4-dihydro-3H-pyrazol-3-one, have been studied by using molecular spectroscopy (UV–Vis and NMR) and quantum-chemical calculations (M06- 2X/TZVP) in solution. The...
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In: ChemPhysChem, 2015, vol. 16, no. 3, p. 649–657
A series of new tautomeric azonaphthols are synthesized and the possibilities for molecular switching are investigated using molecular spectroscopy, X-ray analysis and density functional theory quantum chemical calculations. Two opposite effects that influence switching are studied: attaching a piperidine sidearm, and adding substituents to the phenyl ring. On the one hand, the attached...
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In: RSC Advances, 2013, vol. 3, no. 47, p. 25410–25416
In a previous communication, we demonstrated a conceptual idea for a tautomeric switching system based on implementation of a flexible piperidine unit in 4- (phenyldiazenyl)naphthalen-1-ol (1). The results showed that a directed shift in the position of the tautomeric equilibrium can be achieved through protonation/deprotonation in a number of solvents. However, the effect of the counter ion...
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