Excited-state intramolecular proton transfer and vibrational relaxation in 2-(2-hydroxyphenyl)benzothiazole

Ding, K. Y.; COURTNEY, S. J.; Strandjord, Andrew; Flom, Steven R.; Friedrich, Donald M.; Barbara, P. F.

doi:10.1021/j100230a018

Cited by 68 publications

(49 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, the lifetime results for HBO-1 in neutral pH show two components of 0.8 and 2.4 ns. According to the previous assignments of the fluorescence lifetimes for HBO in different solvents31323435364445, the short component is due to contribution from a closed syn -keto tautomer (τ 2 ) and the long component is the fluorescence decay of the anion species (τ 3 ). It is important to mention here that HBO-1 does not favor the formation of an open syn -keto, in contrast to both HBO and HBO-2.…”

Section: Resultsmentioning

confidence: 91%

Detecting local heterogeneity and ionization ability in the head group region of different lipidic phases using modified fluorescent probes

Abou‐Zied

Zahid

Khyasudeen

et al. 2015

Sci Rep

View full text Add to dashboard Cite

Local heterogeneity in lipid self-assembly is important for executing the cellular membrane functions. In this work, we chemically modified 2-(2′-hydroxyphenyl)benzoxazole (HBO) and attached a C8 alkyl chain in two different locations to probe the microscopic environment of four lipidic phases of dodecyl β-maltoside. The fluorescence change in HBO and the new probes (HBO-1 and HBO-2) shows that in all phases (micellar, hexagonal, cubic and lamellar) three HBO tautomeric species (solvated syn-enol, anionic, and closed syn-keto) are stable. The formation of multi tautomers reflects the heterogeneity of the lipidic phases. The results indicate that HBO and HBO-1 reside in a similar location within the head group region, whereas HBO-2 is slightly pushed away from the sugar-dominated area. The stability of the solvated syn-enol tautomer is due to the formation of a hydrogen bond between the OH group of the HBO moiety and an adjacent oxygen atom of a sugar unit. The detected HBO anions was proposed to be a consequence of this solvation effect where a hydrogen ion abstraction by the sugar units is enhanced. Our results point to a degree of local heterogeneity and ionization ability in the head group region as a consequence of the sugar amphoterism.

show abstract

Section: Resultsmentioning

confidence: 91%

Detecting local heterogeneity and ionization ability in the head group region of different lipidic phases using modified fluorescent probes

Abou‐Zied

Zahid

Khyasudeen

et al. 2015

Sci Rep

View full text Add to dashboard Cite

show abstract

“…There is also a difference in the temporal behaviour of the fluorescence decay of the rotamer and the formation of the tautomer [18,39]. These evidences indicate that the electronic excitation of the species leads to the ESIPT product from only one of the two rotameric forms in selected solvents [23,25,27,28,[33][34][35]37,[39][40][41][42][43][44][45][46][47][48][49][50]. Mordzinski and Grellmann suggested that a thermally activated radiationless transition dominates the decay of the photoproduced keto form at room temperature, whereas, at lower temperature, fluorescence and intersystem crossing are the main deactivation processes [40].…”

Section: Introductionmentioning

confidence: 86%

Theoretical Modelling for the Ground State Rotamerisation and Excited State Intramolecular Proton Transfer of 2-(2’-hydroxyphenyl)oxazole, 2-(2’-hydroxyphenyl)imidazole, 2-(2’-hydroxyphenyl)thiazole and Their Benzo Analogues

Purkayastha

Chattopadhyay

2003

IJMS

View full text Add to dashboard Cite

Two series of compounds, one comprising of 2-(2′-hydroxyphenyl)benzoxazole (HBO), 2-(2′-hydroxyphenyl)benzimidazole (HBI), 2-(2′-hydroxyphenyl)benzothiazole (HBT), and the other of 2-(2′-hydroxyphenyl)oxazole (HPO), 2-(2′-hydroxyphenyl)imidazole (HPI) and 2-(2′-hydroxyphenyl)thiazole (HPT) are susceptible to ground state rotamerization as well as excited state intramolecular proton transfer (ESIPT) reactions. Some of these compounds show experimental evidence of the existence of two ground state conformers. Out of these two one undergoes ESIPT reaction leading to the formation of the tautomer. The two photophysical processes, in combination, result in the production of a number of fluorescence bands each one of which corresponding to a particular species. Semiempirical AM1-SCI calculations have been performed to rationalize the photophysical behaviour of the compounds. The calculations suggest that for the first series of compounds, two rotational isomers are present in the ground state of HBO and HBI while HBT has a single conformer under similar circumstances. For the molecules of the other series existence of rotamers depends very much on the polarity of the environment. The potential energy curves (PEC) for the ESIPT process in different electronic states of the molecules have been generated theoretically. The simulated PECs reveal that for all these systems the IPT reaction is unfavourable in the ground state but feasible, both kinetically and thermodynamically, in the S 1 as well as T 1 states.

show abstract

“…BZT has been studied extensively in the solution state, owing to its interesting proton transfer kinetics. Barbara et al demonstrated that the two intense emission peaks at 480 and 520 nm could be attributed to the H-transferred keto-enol tautomeric structures respectively in the solution state [11,12]. However, in the solid state, energetically favored 'enol' form is preferred.…”

Section: Introductionmentioning

confidence: 95%

Electroluminescent properties of dimeric bis(2-(2′-hydroxyl phenyl)benzthiazolate)zinc (II) complex

Qureshi¹,

Manoharan²,

Singh³

et al. 2005

Solid State Communications

View full text Add to dashboard Cite

Excited-state intramolecular proton transfer and vibrational relaxation in 2-(2-hydroxyphenyl)benzothiazole

Cited by 68 publications

References 0 publications

Detecting local heterogeneity and ionization ability in the head group region of different lipidic phases using modified fluorescent probes

Detecting local heterogeneity and ionization ability in the head group region of different lipidic phases using modified fluorescent probes

Theoretical Modelling for the Ground State Rotamerisation and Excited State Intramolecular Proton Transfer of 2-(2’-hydroxyphenyl)oxazole, 2-(2’-hydroxyphenyl)imidazole, 2-(2’-hydroxyphenyl)thiazole and Their Benzo Analogues

Electroluminescent properties of dimeric bis(2-(2′-hydroxyl phenyl)benzthiazolate)zinc (II) complex

Contact Info

Product

Resources

About