Theoretical Study by Density Functional Theory Method (DFT) of Stability, Tautomerism, Reactivity and Prediction of Acidity of Quinolein-4-One Derivatives

• 作者: Affoué Lucie Bédé Amon Benjamine Assoma Boka Robert N’Guessan El-Hadji Sawaliho Bamba Kicho Denis Yapo Mamadou Guy-Richard Koné Mawa Koné Soleymane Koné
• 来源期刊: 计算化学(英文)
• 学科: 化学
• 关键词: Quinolein-4-One TAUTOMERS Equilibrium Constants Global DESCRIPTORS Dual DESCRIPTORS
• 年，卷（期）: 2018,（3）
• 页码范围: 57-70
• 页数: 14页
• 分类号: O6

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.