Browsing by Author "Henry Chermette"

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    Degradation by hydrolysis of three triphenylmethane dyes: DFT and TD‑DFT study
    (2023) Djamel Taharchaouche; Nadjia Latelli; Hafda Merouani; Boussebbat Wahiba; Naima Mechehoud; Nadia Ouddai; Christophe Morell; Lynda Merzoud; Henry Chermette
    DFT reactivity descriptors, the ultraviolet–visible spectra and hydrolysis mechanism of three cationic dyes [Malachite Green (MG), Brilliant Green (BG) and Ethyl Green (EG)] are performed with several exchange–correlation functional (global GGA, hybrids and range-separated). Using time-dependent density functional theory, the theoretical ultraviolet–visible absorption spectra of the three cationic dyes are obtained and obey the trend for the λmax: GGA>hybrid>range-separated functional. Thanks to the transition state theory, the barriers of hydrolysis mechanism of the cation structures dyes were obtained in gas and solution phase. It is shown that, for these systems the barriers are in order: BG+ < MG+ < EG2+ in gas and solution phase. In the two phases, the CAM-B3LYP functional gives the highest barriers and the M06 gives the lowest ones
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    DFT study of the condensation products of 2‑chloro‑3‑formylquinolines with o‑aminophenol, o‑aminothiophenol and o‑phenylenediamine
    (2023) Nabila Benabila; Hafda Merouani; Nadjia Latelli; Abd Alghani May; Christophe Morell; Lynda Merzoud; Henry Chermette
    The reaction mechanism for the synthesis of quinoline-fused benzo/dia/oxa/thia/zepins is investigated using the DFT/ B3LYP/6-31G(d) method. DFT conceptual reactivity indices analysis allows classifcation of o-aminophenol (2, X =O), o-aminothiophenol (2, X=S) and o-phenylenediamine (2, X=N) and R-substituted 2-chloroquinoline-3-carbaldehydes (1 ac) as strong electrophiles, suggesting a polar process. Besides, Parr functions and Fukui indices predict the most reactive sites for observed experimentally product formation, in agreement with the dual descriptor analysis. In the energy aspect, there is no efect of the R (R= CH3, OCH3) substituent on the thermodynamic quantities, whereas the substitution of the X has a remarkable efect. The products (4a–c, X=N) are the most stable, and their cyclizations are the easiest. An extended analysis was performed using the activation strain model/energy decomposition analysis ASM/EDA model. The obtained results indicate that the orbital interaction and electrostatic stabilizations are the principal factors favoring the reaction with X=N. Topological analysis of the electron localization function (ELF) of the bending point structures along the reaction path indicates that the reaction occurs via a non-concerted two-step mechanism