Ground and excited state prototropic reactions in 2-(o-hydroxyphenyl)benzimidazole

Sinha, Hemant K.; Dogra, Sneh K.

doi:10.1016/0301-0104(86)80006-4

Cited by 141 publications

(160 citation statements)

References 23 publications

Supporting

Mentioning

137

Contrasting

Order By: Relevance

“…Hence, although the IPT process in infeasible in the ground state, the photoinduced proton transfer reaction is feasible in the S 1 and the T 1 states from both thermodynamic and kinetic reasons. The activation barriers from our calculations appear to be a little higher than the experimental values [11,16,25,27,37,48,53]. This deviation may be because of the fact that the short range specific interactions, like hydrogen bonding, have not been considered in the present work.…”

Section: Intramolecular Proton Transfercontrasting

confidence: 58%

“…Equilibrium parameters of different photoisomers of HBO, HBI, HBT and HPO, HPI, HPT in different electronic states. R [7][8][9][10][11][12][13][14][15][16][17] represents the interatomic distance between the two atoms for the first series and R [8][9][10][11][12][13] represents it for the other series referred to by the numbers (see Scheme 1). T 7-8-10-11 is the torsional angle developed by the atoms of the first series and T 2-1-7-8 is that developed by those of the second series.…”

Section: Resultsmentioning

confidence: 99%

“…2.54  4.00 R [8][9][10][11][12][13] 2.14  1.00 normal and rotameric forms and thus rules out the independent existence of the rotamer. The instability of the rotamer of HBT has been supported by Nagaoka et al [44] from their ab initio calculations.…”

Section: Intramolecular Rotationmentioning

confidence: 99%

“…The huge potential in the ESIPT process has provoked massive interest among the photophysicists and photochemists. Studies range from the choice of a variety of homo-and heterocyclic aromatic molecular systems to a wide variety of pure and mixed homogeneous and microheterogeneous solvents [1][2][3][4][5][6][7][8][9][10][11]. This phenomenon has widespread implications in photostabilizers [12], laser dyes [13] and also in the biological fields [14].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

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

Section: Intramolecular Proton Transfercontrasting

confidence: 58%

Section: Resultsmentioning

confidence: 99%

Section: Intramolecular Rotationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

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

show abstract

“…The introduction of aromatic 2-substituents with heteroatoms brings additional protonation possibilities (4-7) and in some cases, e.g., those of 2-(2'-hydroxypheny1)benzimidazole (8) and 2-(2'-aminophenyl)benzimidazole (9), the formation of intramolecular hydrogen bonds.…”

Section: Introductionmentioning

confidence: 99%

Prototropic equilibria of 2-pyridylbenzimidazoles in aqueous solution

Novo¹,

Mosquera²,

Rodríguez‐Prieto³

1992

Can. J. Chem.

View full text Add to dashboard Cite

MERCEDES NOVO, MANUEL MOSQUERA, and FLOR RODR~GUEZ PRIETO. Can. J . Chem. 70, 823 (1992). In this paper we report the acid-base behaviour of 2-(nf-pyridy1)benzimidazoles (11' = 2,3,4) and some methyl derivatives in aqueous solution over a wide range of acidity, involving interesting features with respect to competition in protonation between the benzimidazole N3 and the pyridyl N, with the existence of the corresponding two monocations in equilibrium in the case of n ' = 4. The influence of pH on the electronic absorption spectra of all compounds has been studied in order to identify the ground-state species present as a function of acidity and to obtain the acidity constants of the various prototropic equilibria occurring in the wide range of acidity studied.

show abstract

Advanced Organic Optoelectronic Materials: Harnessing Excited‐State Intramolecular Proton Transfer (ESIPT) Process

2011

View full text Add to dashboard Cite

Recently, organic fluorescent molecules harnessing the excited-state intramolecular proton transfer (ESIPT) process are drawing great attention due to their unique photophysical properties which facilitate novel optoelectronic applications. After a brief introduction to the ESIPT process and related photo-physical properties, molecular design strategies towards tailored emission are discussed in relation to their theoretical aspects. Subsequently, 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).

show abstract

Ground and excited state prototropic reactions in 2-(o-hydroxyphenyl)benzimidazole

Cited by 141 publications

References 23 publications

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

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

Prototropic equilibria of 2-pyridylbenzimidazoles in aqueous solution

Advanced Organic Optoelectronic Materials: Harnessing Excited‐State Intramolecular Proton Transfer (ESIPT) Process

Contact Info

Product

Resources

About