scholarly journals Grids to Illustrate Induction and Resonance Effects: Aromatic Acidity and Basicity

2020 ◽  
Author(s):  
Guy Lamoureux ◽  
Carlos Árias-Alvarez
Keyword(s):  
Educational Process ◽  
Benzoic Acids ◽  
Resonance Effects ◽  
Effect Of Substituents ◽  
Acidity And Basicity

The effect of substituents on the acidity of benzoic acids and anilines has been organized in grids to demonstrate the inductive and resonance effects. The relation between structure and pKa is emphasized by a new educational process: the Search-Organize-Predict (SOP) procedure.

scholarly journals Grids to Illustrate Induction and Resonance Effects: Aromatic Acidity and Basicity

2020 ◽  
Author(s):  
Guy Lamoureux ◽  
Carlos Árias-Alvarez
Keyword(s):  
Educational Process ◽  
Benzoic Acids ◽  
Resonance Effects ◽  
Effect Of Substituents ◽  
Acidity And Basicity

The effect of substituents on the acidity of benzoic acids and anilines has been organized in grids to demonstrate the inductive and resonance effects. The relation between structure and pKa is emphasized by a new educational process: the Search-Organize-Predict (SOP) procedure.

Kinetic study of hydrolysis of benzoates. part xxvii. ortho substituent effect in alkaline hydrolysis of phenyl esters of substituted benzoic acids in aqueous Bu4NBr

2009 ◽  
Vol 74 (1) ◽  
pp. 29-42 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Signe Vahur ◽  
Oksana Travnikova ◽  
Ilmar A. Koppel
Keyword(s):  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Pure Water ◽  
Substituent Effects ◽  
Benzoic Acids ◽  
Resonance Effects ◽  
The Media ◽  
Substituted Benzoic Acids ◽  
Hydrolysis Of ◽  
Ortho Substituent

The second-order rate constants k (in dm3 mol–1 s–1) for alkaline hydrolysis of phenyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2C6H5, have been measured spectrophotometrically in aqueous 0.5 and 2.25 M Bu4NBr at 25 °C. The substituent effects for para and meta derivatives were described using the Hammett relationship. For the ortho derivatives the Charton equation was used. For ortho-substituted esters two steric scales were involved: the EsB and the Charton steric (υ) constants. When going from pure water to aqueous 0.5 and 2.25 M Bu4NBr, the meta and para polar effects, the ortho inductive and resonance effects in alkaline hydrolysis of phenyl esters of substituted benzoic acids, became stronger nearly to the same extent as found for alkaline hydrolysis of C6H5CO2C6H4-X. The steric term of ortho-substituted esters was almost independent of the media considered. The rate constants of alkaline hydrolysis of ortho-, meta- and para-substituted phenyl benzoates (X-C6H4CO2C6H5, C6H5CO2C6H4-X) and alkyl benzoates, C6H5CO2R, in water, 0.5 and 2.25 M Bu4NBr were correlated with the corresponding IR stretching frequencies of carbonyl group, (ΔνCO)X.

scholarly journals Spectral Correlations in some Substituted Styryl (E)-4-((2-Oxopropyl)Diazenyl) Benzoic Acids

2014 ◽  
Vol 30 ◽  
pp. 33-43
Author(s):  
V. Sathiyendiran ◽  
K.G. Sekar ◽  
Ganesamoorthy Thirunarayanan ◽  
R. Arulkumaran ◽  
R. Sundararajan ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Statistical Analysis ◽  
Linear Regression ◽  
Linear Regression Analysis ◽  
Benzoic Acids ◽  
Effect Of Substituents ◽  
Substituent Constants ◽  
Multi Linear Regression ◽  
Spectral Group

A series of titled compounds were prepared and analyzed their purities by literature method. The infrared and NMR spectral group frequencies of the compounds were assigned and correlated with Hammett substituent constants, F and R constants using single and multi linear regression analysis. From the results of statistical analysis, the effect of substituents on the above spectral frequencies was discussed.

scholarly journals Analysis of the Gas Phase Acidity of Substituted Benzoic Acids Using Density Functional Concepts

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1631
Author(s):  
Jorge A. Amador-Balderas ◽  
Michael-Adán Martínez-Sánchez ◽  
Ramsés E. Ramírez ◽  
Francisco Méndez ◽  
Francisco J. Meléndez
Keyword(s):  
Gas Phase ◽  
Density Functional ◽  
Chemical Potential ◽  
Fukui Function ◽  
Ortho Position ◽  
Benzoic Acids ◽  
Functional Theory ◽  
Resonance Effects ◽  
Gas Phase Acidity ◽  
Substituted Benzoic Acids

A theoretical study of the effect of the substituent Z on the gas phase acidity of substituted benzoic acids ZC6H4COOH in terms of density functional theory descriptors (chemical potential, softness and Fukui function) is presented. The calculated gas phase ΔacidG° values obtained were close to the experimental ones reported in the literature. The good relationship between the ΔacidG° values and the electronegativity of ZC6H4COOH 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 -SO2CF3 and -NH2 substituents in the para- and ortho-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 ortho > meta > para, and the electron-withdrawing substituent increased the acidity in the trend ortho < meta < para.

Synthesis of perbromobenzoic acids and perbromobenzenes from aromatic carboxylic acids by permercuration and bromodemercuration

1977 ◽  
Vol 30 (2) ◽  
pp. 293 ◽  
Author(s):  
GB Deacon ◽  
GJ Farquharson
Keyword(s):  
Thermal Decomposition ◽  
Carboxylic Acids ◽  
Carboxyl Group ◽  
Benzoic Acids ◽  
Similar Treatment ◽  
Aromatic Carboxylic Acids ◽  
Effect Of Substituents

Permercuration of the benzoic acids XC6H4CO2H (X = o-Me, F, Cl, or Br; m- Me, F, Cl, Br, CF3, NO2 or OMe; or p-Me, F, Cl, Br, CF3 or NO2) and 2,6- X2C6H3CO2H (X = Me, Cl, or Br) with molten mercuric trifluoroacetate at c. 180-245° followed by bromodemercuration gave the corresponding perbromobenzoic acids XC6Br4CO2H or 2,6-X2C6Br3CO2H, together with the corresponding perbromobenzenes C6Br5X or m-X2C6Br4 which were formed owing to decarboxylation under permercuration conditions. Similar treatment of the acids XC6H4CO2H (X = o-NO2, CF3, or OMe; or p-OMe) and 2,6-F2C6H3CO2H gave only the appropriate perbromobenzenes. Possible mechanisms for permercuration induced decarboxylation are proposed on the basis of the effect of substituents on yields of perbromobenzoic acids and perbromobenzenes. Decarboxylation occurs more widely under permercuration conditions than on pyrolysis of mercuric carboxylates. Regiospecific mercuration meta to the carboxyl group and not decarboxylation occurred on thermal decomposition of mercuric p-methoxybenzoate.

scholarly journals Grids to Illustrate Induction and Resonance Effects: Electrophilic Aromatic Substitution

2020 ◽  
Author(s):  
Guy Lamoureux ◽  
Carlos Árias-Alvarez
Keyword(s):  
Undergraduate Students ◽  
Electrophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Resonance Effects ◽  
Effect Of Substituents

The effect of substituents on the reactivity in electrophilic aromatic substitution has been organized in a grid to demonstrate the inductive and resonance effects. This scheme can also incorporate the competition between donation and withdrawal. In class games are proposed from which undergraduate students can practice the effects while playing.

scholarly journals Grids to Illustrate Induction and Resonance Effects: Electrophilic Aromatic Substitution

2020 ◽  
Author(s):  
Guy Lamoureux ◽  
Carlos Árias-Alvarez
Keyword(s):  
Undergraduate Students ◽  
Electrophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Resonance Effects ◽  
Effect Of Substituents

The effect of substituents on the reactivity in electrophilic aromatic substitution has been organized in a grid to demonstrate the inductive and resonance effects. This scheme can also incorporate the competition between donation and withdrawal. In class games are proposed from which undergraduate students can practice the effects while playing.

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