Étude de la tautomérie du v-triazole à partir des mesures des moments dipolaires

Mauret, P.; Fayet, Jean-Pierre; Fabre, Martine; Elguero, José; Mendoza, Javier de

doi:10.1051/jcp/1973701483

Cited by 16 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although 1‐methylpyrrole, 1‐methylindole, and 1‐methylcarbazole are all dipolar — their respective ground‐state dipole moments are μ g = 2.12 ± 0.02, 2.11, and 1.99 D —, their solvatochromism is strongly dependent on the polarizability of the medium, with regression coefficients of 422 ± 91, 762 ± 71, and 1125 ± 50 for the SP term in Eqns , , and , respectively. This result confirms that electronic excitation to a π* orbital not only increases the polarizability of these compounds, but also indicates that the solvent influence increases with the increasing size of the aromatic backbone: pyrrole < indole < carbazole.…”

Section: Resultsmentioning

confidence: 99%

Compounds with π(loc ) → π(deloc* ) electronic transitions and their solvatochromism

Catalán¹

2015

J. Phys. Org. Chem.

View full text Add to dashboard Cite

Molecular structures possessing atomic sites that contribute a non‐bonding electron pair to their π system (e.g. nitrogen atoms with sp2 hybridization in pyrroles and anilines) usually exhibit a first absorption band whose solvatochromism is, surprisingly, sensitive only to the polarizability of the medium even though they are dipolar. As shown here, this solvatochromic behavior is a result of the first electronic transition in these compounds occurring from a substantially localized π orbital to a substantially delocalized π* orbital in the molecular structure. The high electronic delocalization present leads to a marked bathochromic band shift as the polarizability of the medium increases. It is especially relevant that this solvatochromism, which is because of the polarizability of the medium, explains the spectral shift that is only because of the redistribution of the electrons of the solvent molecules. It is important to take into account that this electronic redistribution happens instantaneously in this process. Copyright © 2015 John Wiley & Sons, Ltd.

show abstract

Section: Resultsmentioning

confidence: 99%

Compounds with π(loc ) → π(deloc* ) electronic transitions and their solvatochromism

Catalán¹

2015

J. Phys. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…For the liquid phases, force field molecular dynamics within the Lammps software [67] and AMBER force field [68] have been simulated for the starting structures. The tautomer ratio of the liquid phase at 313 K is taken from Mauret [49]. The liquid phase at 413 K has the purpose to serve as a model system at elevated temperature and therefore was also chosen to have the same tautomer ratio as the liquid phase at 313 K.…”

Section: Methodsmentioning

confidence: 99%

“…This symmetry influences the behavior dramatically as the resulting dipole is 42 times bigger in case of the non symmetrical 1H-triazole [45]. This property is reflected in the tautomer ratio found for different temperatures as well as in gas phase [43,45,49]. The higher the temperature gets, the more the 2H-triazole (less polar) is dominating.…”

Section: Introductionmentioning

confidence: 98%

ab-Initio Study of Hydrogen Bond Networks in 1,2,3-Triazole Phases

2020

View full text Add to dashboard Cite

The research in storage and conversion of energy is an everlasting process. The use of fuel cells is very tempting but up to now there are still several conceptual challenges to overcome. Especially, the requirement of liquid water causes difficulties due to the temperature limit. Therefore, imidazoles and triazoles are increasingly investigated in a manifold of experimental and theoretical publications as they are both very promising in overcoming this problem. Recently, triazoles were found to be superior to imidazoles in proton conduction. An ab-initio molecular dynamics simulation of pure triazole phases for investigating the behavior of both tautomer species of the triazole molecule has never been done. In this work, we investigate the structural and dynamical properties of two different solid phases and the liquid phase at two different temperatures. We are able to show how the distinct tautomers contribute to the mechanism of proton conduction, to compute dynamical properties of the four systems and to suggest a mechanism of reorientation in solid phase.

show abstract

“…The structures of the azoles studied are shown in Figure 1. For several of the azoles, two tautomeric forms are present in equilibrium 25, 26. In these cases only the more stable, lower‐energy tautomer in a particular phase has been used in the regressions.…”

Section: Methodsmentioning

confidence: 99%

Theoretical estimation of the acidities of alcohols and azoles in gas phase, DMSO, and water

Seybold

Kreye

2012

Int J of Quantum Chemistry

View full text Add to dashboard Cite

Most acidities and basicities of chemical compounds are measured in aqueous solution since this solvent is most important for biochemical and environmental applications, but the acidities of compounds in the gas phase and in other solvents can also be of interest. As a polar, aprotic solvent, dimethyl sulfoxide (DMSO) presents a unique environment for acid dissociation, and this solvent offers informative comparisons with both the vacuum and aqueous environments. Here, quantum chemical approaches previously used for the estimation of aqueous pKa values are applied to the estimation of DMSO, aqueous, and gas‐phase acidities for two representative series of compounds: alcohols/phenols and azoles. Calculations were performed using both the semiempirical RM1 method and density functional theory (B3LYP/6‐31+G**). The effectiveness of the SM5.4 and SM8 solvent models in estimating the solution‐phase acidities was also examined. © 2012 Wiley Periodicals, Inc.

show abstract

Étude de la tautomérie du v-triazole à partir des mesures des moments dipolaires

Cited by 16 publications

References 0 publications

Compounds with π(loc ) → π(deloc* ) electronic transitions and their solvatochromism

Compounds with π(loc ) → π(deloc* ) electronic transitions and their solvatochromism

ab-Initio Study of Hydrogen Bond Networks in 1,2,3-Triazole Phases

Theoretical estimation of the acidities of alcohols and azoles in gas phase, DMSO, and water

Contact Info

Product

Resources

About

Étude de la tautomérie du v-triazole à partir des mesures des moments dipolaires

Cited by 16 publications

References 0 publications

Compounds with π(loc ) → π*(deloc ) electronic transitions and their solvatochromism

Compounds with π(loc ) → π*(deloc ) electronic transitions and their solvatochromism

ab-Initio Study of Hydrogen Bond Networks in 1,2,3-Triazole Phases

Theoretical estimation of the acidities of alcohols and azoles in gas phase, DMSO, and water

Contact Info

Product

Resources

About

Compounds with π(loc ) → π(deloc* ) electronic transitions and their solvatochromism

Compounds with π(loc ) → π(deloc* ) electronic transitions and their solvatochromism