Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts
A theoretical study of the effect of the substituent Z on the gas phase acidity of substituted benzoic acids ZC<sub>6</sub>H<sub>4</sub>COOH in terms of density functional theory descriptors (chemical potential, softness and Fukui function) is presented. The calculated gas ph...
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| Format: | Article |
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MDPI AG
2020-04-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/25/7/1631 |
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| author | Jorge A. Amador-Balderas Michael-Adán Martínez-Sánchez Ramsés E. Ramírez Francisco Méndez Francisco J. Meléndez |
| author_facet | Jorge A. Amador-Balderas Michael-Adán Martínez-Sánchez Ramsés E. Ramírez Francisco Méndez Francisco J. Meléndez |
| author_sort | Jorge A. Amador-Balderas |
| collection | DOAJ |
| description | A theoretical study of the effect of the substituent Z on the gas phase acidity of substituted benzoic acids ZC<sub>6</sub>H<sub>4</sub>COOH in terms of density functional theory descriptors (chemical potential, softness and Fukui function) is presented. The calculated gas phase Δ<sub>acid</sub><i>G</i>° values obtained were close to the experimental ones reported in the literature. The good relationship between the Δ<sub>acid</sub><i>G</i>° values and the electronegativity of ZC<sub>6</sub>H<sub>4</sub>COOH and its fragments, suggested a better importance of the inductive than polarizability contributions. The balance of inductive and resonance contributions of the substituent in the acidity of substituted benzoic acids showed that the highest inductive and resonance effects were for the -SO<sub>2</sub>CF<sub>3</sub> and -NH<sub>2</sub> substituents in the <i>para</i>- and <i>ortho</i>-position, respectively. The Fukui function confirmed that the electron-releasing substituent attached to the phenyl ring of benzoic acid decreased the acidity in the trend <i>ortho</i> > <i>meta</i> > <i>para</i><b>,</b> and the electron-withdrawing substituent increased the acidity in the trend <i>ortho</i> < <i>meta</i> < <i>para</i>. |
| first_indexed | 2024-03-10T20:44:12Z |
| format | Article |
| id | doaj.art-ba74229464fd4ad9b4c904d927c9f9c9 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T20:44:12Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-ba74229464fd4ad9b4c904d927c9f9c92023-11-19T20:28:51ZengMDPI AGMolecules1420-30492020-04-01257163110.3390/molecules25071631Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional ConceptsJorge A. Amador-Balderas0Michael-Adán Martínez-Sánchez1Ramsés E. Ramírez2Francisco Méndez3Francisco J. Meléndez4Departamento de Fisicomatemáticas, Facultad de Ciencias Químicas, Av. San Claudio y 14 Sur, Col. San Manuel, Benemérita Universidad Autónoma de Puebla, C.P. 72570, Puebla, Pue., MexicoDepartamento de Química, División de Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Mexico, D.F., 09340 MexicoDepartamento de Fisicomatemáticas, Facultad de Ciencias Químicas, Av. San Claudio y 14 Sur, Col. San Manuel, Benemérita Universidad Autónoma de Puebla, C.P. 72570, Puebla, Pue., MexicoDepartamento de Química, División de Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Mexico, D.F., 09340 MexicoDepartamento de Fisicoquímica, Facultad de Ciencias Químicas, Av. San Claudio y 14 Sur, Col. San Manuel, Benemérita Universidad Autónoma de Puebla, C.P. 72570, Puebla, Pue., MexicoA theoretical study of the effect of the substituent Z on the gas phase acidity of substituted benzoic acids ZC<sub>6</sub>H<sub>4</sub>COOH in terms of density functional theory descriptors (chemical potential, softness and Fukui function) is presented. The calculated gas phase Δ<sub>acid</sub><i>G</i>° values obtained were close to the experimental ones reported in the literature. The good relationship between the Δ<sub>acid</sub><i>G</i>° values and the electronegativity of ZC<sub>6</sub>H<sub>4</sub>COOH and its fragments, suggested a better importance of the inductive than polarizability contributions. The balance of inductive and resonance contributions of the substituent in the acidity of substituted benzoic acids showed that the highest inductive and resonance effects were for the -SO<sub>2</sub>CF<sub>3</sub> and -NH<sub>2</sub> substituents in the <i>para</i>- and <i>ortho</i>-position, respectively. The Fukui function confirmed that the electron-releasing substituent attached to the phenyl ring of benzoic acid decreased the acidity in the trend <i>ortho</i> > <i>meta</i> > <i>para</i><b>,</b> and the electron-withdrawing substituent increased the acidity in the trend <i>ortho</i> < <i>meta</i> < <i>para</i>.https://www.mdpi.com/1420-3049/25/7/1631absolute gas phase acidityFukui functionchemical potentialsoftnessnucleophileelectrophile |
| spellingShingle | Jorge A. Amador-Balderas Michael-Adán Martínez-Sánchez Ramsés E. Ramírez Francisco Méndez Francisco J. Meléndez Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts Molecules absolute gas phase acidity Fukui function chemical potential softness nucleophile electrophile |
| title | Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts |
| title_full | Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts |
| title_fullStr | Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts |
| title_full_unstemmed | Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts |
| title_short | Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts |
| title_sort | analysis of the gas phase acidity of substituted benzoic acids using density functional concepts |
| topic | absolute gas phase acidity Fukui function chemical potential softness nucleophile electrophile |
| url | https://www.mdpi.com/1420-3049/25/7/1631 |
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