Effect of para Substitution on Dissociation of N-Phenylbenzenesulfonamides

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Title:Effect of para Substitution on Dissociation of N-Phenylbenzenesulfonamides
Creators:
Mansfeld, Martin
Pařík, Patrik
Ludwig, Miroslav
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 69, 7, pp. 1479-1490
Uncontrolled Keywords:Sulfonamides, Transmission effect, Hammett equation, Chemometrics, Dissociation constant, Acidity, Substituent effects

Abstract

The reaction of substituted anilines and benzenesulfonyl chlorides has been used to prepare 49 substituted <i>N</i>-phenylbenzenesulfonamides of general formula 4-X-C<sub>6</sub>H<sub>4</sub>SO<sub>2</sub>NHC<sub>6</sub>H<sub>4</sub>-Y-4'. Their purity was checked by elemental analysis. The substituents X and Y include H, CH<sub>3</sub>, CH<sub>3</sub>O, Cl, Br, CN, and NO<sub>2</sub>. The dissociation constants of all compounds were determined by potentiometric titration in methanol, acetonitrile, <i>N</i>,<i>N</i>-dimethylformamide, and pyridine. The obtained dissociation constants, p<i>K</i><sub>HA</sub>, were correlated with various sets of substituent constants. It was found that the effects of substituents X and Y on the dissociation are best described by using the Hammett equation with σ<sub>p</sub> constants and the Yukawa-Tsuno equation with σ<sub>p</sub><sup>-</sup> and σ<sub>p</sub> constants, respectively. This result confirms the direct conjugation of Y substituent with the reaction centre. The explained variability using the additive model was above 96% in all the solvents used. The data also provided information about the transmission effect of the SO<sub>2</sub> group. The average dissociation constants were further processed by the latent variables methods, principal components and conjugated deviations analyses. <p>

Title:Effect of para Substitution on Dissociation of N-Phenylbenzenesulfonamides
Creators:
Mansfeld, Martin
Pařík, Patrik
Ludwig, Miroslav
Uncontrolled Keywords:Sulfonamides, Transmission effect, Hammett equation, Chemometrics, Dissociation constant, Acidity, Substituent effects
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:69
Number:7
Page Range:pp. 1479-1490
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc20041479UNSPECIFIED
ID Code:2287
Item Type:Article
Deposited On:06 Feb 2009 17:17
Last Modified:06 Feb 2009 16:17

Citation

Mansfeld, Martin; Pařík, Patrik; Ludwig, Miroslav (2004) Effect of para Substitution on Dissociation of N-Phenylbenzenesulfonamides. Collection of Czechoslovak Chemical Communications, 69 (7). pp. 1479-1490. ISSN 0010-0765

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