NH-acidities and Hammett correlation of 3-para substituted phenyl-1,2,4-oxadiazol-5(4H)-ones and 1,2 λ4 3,5-oxathiadiazole 2-oxides in nonaqueous media
NH acidities of some 3-( p -substitutedphenyl)-1,2,4-oxadiazol-5(4 H) -ones and 4-( p -substitutedphenyl)-1,2 λ4 3,5-oxathiadiazole 2-oxides were determined in methanol by means of potentiometric titration with sodium methoxide. pK a values of the title compounds calculated from the potentiometric data were interpreted on the basis of structural effects caused by para-substituted groups on the phenyl ring by plotting pK a values versus Hammett σp + constants, which gave excellent linear correlations.
📌 3 Key Takeaways
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Objective & Hypothesis:NH acidities of some 3-( p -substitutedphenyl)-1,2,4-oxadiazol-5(4 H) -ones and 4-( p -substitutedphenyl)-1,2 λ4 3,5-oxathiadiazole 2-oxides were determined in methanol by means of potentiometric titration with sodium methoxide. pK a values of the title compounds calculated from the potentiometric data were interpreted on the basis of structural effects caused by para-substituted groups on the phenyl ring by plotting pK a values versus Hammett σp + constants, which gave excellent linear correlations.
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Key Findings & Data:NH acidities of some 3-( p -substitutedphenyl)-1,2,4-oxadiazol-5(4 H) -ones and 4-( p -substitutedphenyl)-1,2 λ4 3,5-oxathiadiazole 2-oxides were determined in methanol by means of potentiometric titration with sodium methoxide. pK a values of the title compounds calculated from the potentiometric data were interpreted on the basis of structural effects caused by para-substituted groups on the phenyl ring by plotting pK a values versus Hammett σp + constants, which gave excellent linear correlations.
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Conclusion & Impact:NH acidities of some 3-( p -substitutedphenyl)-1,2,4-oxadiazol-5(4 H) -ones and 4-( p -substitutedphenyl)-1,2 λ4 3,5-oxathiadiazole 2-oxides were determined in methanol by means of potentiometric titration with sodium methoxide. pK a values of the title compounds calculated from the potentiometric data were interpreted on the basis of structural effects caused by para-substituted groups on the phenyl ring by plotting pK a values versus Hammett σp + constants, which gave excellent linear correlations.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters
Abstract
NH acidities of some 3-( p -substitutedphenyl)-1,2,4-oxadiazol-5(4 H) -ones and 4-( p -substitutedphenyl)-1,2 λ4 3,5-oxathiadiazole 2-oxides were determined in methanol by means of potentiometric titration with sodium methoxide. pK a values of the title compounds calculated from the potentiometric data were interpreted on the basis of structural effects caused by para-substituted groups on the phenyl ring by plotting pK a values versus Hammett σp + constants, which gave excellent linear correlations.
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Cite This Article
DÜRÜST, N., DÜRÜST, Y., GÖZLÜKAYA, E. Ö. (2022). NH-acidities and Hammett correlation of 3-para substituted phenyl-1,2,4-oxadiazol-5(4H)-ones and 1,2 λ4 3,5-oxathiadiazole 2-oxides in nonaqueous media. Turkish Journal of Chemistry, Cilt: 38 - Sayı: 1, 56–62. https://ajindex.com/articles/589527
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