Investigations on acid/base-catalyzed hydrolysis mechanisms of mono(2-hydroxyethyl) terephthalate using quantum chemistry methods

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry Pub Date : 2025-03-06 DOI:10.1016/j.comptc.2025.115163

Weifeng Xu , Yang Long , Song Chen , Jinbao Huang , Hong Wang , Li Jin , Jun Cheng , Xinsheng Li

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Abstract

The mechanisms and kinetics of acid/base-catalyzed hydrolysis of PET model compound, mono(2-hydroxyethyl) terephthalate (MHET), were evaluated by quantum chemical methods. For acid-catalyzed hydrolysis, the most feasible degradation pathways involved the protonation of the most negative potential oxygen atom O_carbonyl. The ester bond was subsequently cleaved to form terephthalic acid (TPA) and a cationic intermediate, with the energy barrier of 94.0 kJ/mol. For base-catalyzed hydrolysis, [OH]⁻ tends to attack the C_carbonyl atom of MHET to form an anionic intermediate, requiring overcoming a barrier height of 158.3 kJ/mol due to the electron outflow from the lone pair of [OH]⁻ to the empty p orbital of the O_carbonyl and O_ester atoms. For solvent effect, a tend was observed that related the reaction energy barrier positive correlation to the polarity of the solvent. Cations are beneficial for stabilizing the transition state, whereas counteranions did not significantly change the reaction energetics.

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来源期刊

Computational and Theoretical Chemistry CHEMISTRY, PHYSICAL-

CiteScore

4.20

自引率

10.70%

发文量

331

审稿时长

31 days

期刊介绍： Computational and Theoretical Chemistry publishes high quality, original reports of significance in computational and theoretical chemistry including those that deal with problems of structure, properties, energetics, weak interactions, reaction mechanisms, catalysis, and reaction rates involving atoms, molecules, clusters, surfaces, and bulk matter.