Journal ArticleDOI
Photoinduced Inter- and Intramolecular Proton Transfer in Aqueous and Ethanolic Solutions of 2-(2‘-Hydroxyphenyl)benzimidazole: Evidence for Tautomeric and Conformational Equilibria in the Ground State†
TLDR
In this paper, the authors investigated the behavior of 2-(2'-hydroxyphenyl)benzimidazole (HBI) in aqueous and ethanolic solutions of HBI by means of UV-vis absorption and fluorescence spectroscopy.Abstract:
Excited-state proton transfer in aqueous and ethanolic solutions of 2-(2‘-hydroxyphenyl)benzimidazole (HBI) was investigated by means of UV−vis absorption and fluorescence spectroscopy. The behavior of HBI in water differed from its behavior in ethanol, and in both solvents fluorescence behavior depended on acidity. In both neutral water and neutral ethanol, ground-state HBI exhibits conformational equilibrium between a cis-enol form with an intramolecular hydrogen bond and a trans-enol form that is hydrogen-bonded to the solvent; the ground-state keto tautomer is also present in water but was not detected in ethanol. The excited cis-enol conformer always undergoes ultrafast intramolecular proton transfer to afford the excited keto tautomer. The excited trans-enol form fluoresces in both solvents, and in water it also loses its hydroxyl proton to the solvent, leaving the excited anion. In both acidic aqueous solution and acidic ethanol, excited protonated HBI loses its hydroxyl proton to give the excited ...read more
Citations
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Journal ArticleDOI
Advanced Organic Optoelectronic Materials: Harnessing Excited-State Intramolecular Proton Transfer (ESIPT) Process
Ji Eon Kwon,Soo Young Park +1 more
TL;DR: Recent studies on advanced ESIPT molecules and their optoelectronic applications are surveyed, particularly focusing on chemical sensors, fluorescence imaging, proton transfer lasers, and organic light-emitting diodes (OLEDs).
Journal ArticleDOI
Excited-state proton coupled charge transfer modulated by molecular structure and media polarization
TL;DR: With knowledge of the mechanisms of these processes, desired rates and directions can be achieved, and thus the multiple emission spectral features can be harnessed.
Journal ArticleDOI
Preventing UV-light damage of light sensitive materials using a highly protective UV-absorbing coating
TL;DR: This tutorial review incorporates the main aspects of UV damage to materials and describes the recently developed highly effective thin UV-protective coatings, based on UV-absorber molecules entrapped in a Sol-Gel derived ormosil matrix.
Journal ArticleDOI
Excited State Intramolecular Proton Transfer and Metal Ion Complexation of 2-(2‘-Hydroxyphenyl)benzazoles in Aqueous Solution
Maged Henary,Christoph J. Fahrni +1 more
TL;DR: In this paper, the excited-state intramolecular proton transfer (ESIPT) of a series of water-soluble 2-(2‘-hydroxyphenyl)benzazole derivatives has been studied under physiological conditions using absorbance and steady-state emission spectroscopy.
Journal ArticleDOI
Aggregation-induced emission enhancement of 2-(2'-hydroxyphenyl)benzothiazole-based excited-state intramolecular proton-transfer compounds.
Yan Qian,Shayu Li,Guoqi Zhang,Qian Wang,Shuangqing Wang,Huijun Xu,Chengzhang Li,Yi Li,Guoqiang Yang +8 more
TL;DR: Different aggregation forms of these two organic compounds, due to the steric hindrance of a single tert-butyl group, could be responsible for the notably different degrees of the fluorescence enhancement.
References
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Journal ArticleDOI
Quantum efficiencies of fluorescence of organic substances: effect of solvent and concentration of the fluorescent solute1
Journal ArticleDOI
Excited-state proton transfer reactions II. Intramolecular reactions
TL;DR: In this paper, the intrinsic processes and mechanisms of proton transfer in relation to the nature of the intramolecular hydrogen bond ring are reviewed. But the authors focus on the intrinsic process and not the mechanisms of transfer.
Journal ArticleDOI
Proton-transfer spectroscopy. Perturbation of the tautomerization potential
TL;DR: In this article, the potential functions for proton-transfer spectroscopy are discussed and the perturbations of these potentials by specific solvation and by spectroscopic solvent-cage effects are discussed on the basis of a Born-Oppenheimer model.
Journal ArticleDOI
Intramolecular excited-state proton transfer in 3-hydroxyflavone. Hydrogen-bonding solvent perturbations
Dale McMorrow,Michael Kasha +1 more
TL;DR: In this article, the phenomenon of excited-state proton transfer in 3-hydroxyflavone is shown to depend sensitively on traces of H-bonding impurities in hydrocarbon solvents.
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