Theoretical Study by Density Functional Theory Method (DFT) of Stability, Tautomerism, Reactivity and Prediction of Acidity of Quinolein-4-One Derivatives
Theoretical Study by Density Functional Theory Method (DFT) of Stability, Tautomerism, Reactivity and Prediction of Acidity of Quinolein-4-One Derivatives作者机构:Laboratoire de Chimie Organique Structurale Université Félix Houphouë t-Boigny Abidjan Cô te d’Ivoire Laboratoire de Thermodynamique et de Physico-Chimie du Milieu Université Nangui Abrogoua Abidjan Cô te d’Ivoire
出 版 物:《Computational Chemistry》 (计算化学(英文))
年 卷 期:2018年第6卷第3期
页 面:57-70页
主 题:Quinolein-4-One Tautomers Equilibrium Constants Global Descriptors Dual Descriptors
摘 要:A theoretical study of the reactivity of quinoline-4-one derivatives is undertaken in order to understand the involved mechanisms. The calculations were carried out in gas phase and in N, N-Dimethylformamide (DMF) solution. The Density Functional Theory (DFT) with B3LYP functional associated to 6-311G (d) and 6-311+G (d) bases is used to perform these calculations. The results of the thermodynamic parameters showed that there is an equilibrium relation between the different tautomers. This equilibrium can be used to explain the failure to obtain tetrahydroquinoline from 5,8-dimethoxy-quinolin-4-one. Reactivity analysis from Frontier Molecular Orbitals theory and Fukui function calculations revealed that ketone forms are less reactive than enol ones. The methoxyl substituent decreases the acidity of the nitrogen and oxygen atoms of quinolin-4-one while the bromine increases the acidity of the same sites. These results foresee that nitrogen deprotonation in the case of the brominated compound is easier than in the case of methoxylated ones.