Quantitative treatment of substituent effects in polarography. VI. Polarographic reduction of benzonitriles m- and p-substituted with electronegative groups

Reduction of 3-cyanopyridinium salts has been studied on the mercury dropping electrode. Solvent and substituent effects and pH of the medium have been shown to modify in a certain extent differently the polarographic characteristics as compared with analogous 3-carbamoyl derivatives, which is due to higher electronegativity of the studied cations.

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Substituent effects on polarographic reduction of some photographic color intermediates

Canadian Journal of Chemistry ◽

10.1139/v76-170 ◽

1976 ◽

Vol 54 (8) ◽

pp. 1205-1210 ◽

Cited By ~ 3

Author(s):

Ahmad S. Shawali ◽

Bahgat E. El-Anadouli

Keyword(s):

Dissociation Constants ◽

Substituent Effects ◽

Protonated Form ◽

Acid Dissociation ◽

Polarographic Reduction ◽

Substituent Constant ◽

Acid Dissociation Constants ◽

Controlled Potential Electrolysis ◽

Half Wave ◽

Controlled Potential

Polarographic reduction of two series of benzoylacetanilides has been investigated in 40% (by volume) ethanolic Britton–Robinson buffers. One series (A) contains substituents on the anilide moiety, and the second (B) has substituents on both the anilide and benzoyl moieties. Polarographic controlled-potential electrolysis data indicate that the electroactive species in both series is the protonated form (ArCOCH2CONHAr′)H+. The reduction half-wave potentials of anilides of series A were found to be independent of the nature of the substituent, whereas those of series B show a good linear relationship when plotted vs. the σ substituent constant of the substituent on the benzoyl moiety (ρ = 0.284, r = 0.995). Values of the acid dissociation constants of the keto (K1) and enol (K2) tautomers of the anilides of series A were calculated; unlike their E1/2 values, the pK1 data show a linear correlation with the Hammett substituent constant, σ. The pK2 values show, however, little variation with σ.

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Substituent effects in the polarographic reduction of t-Butyl phenyl ketones and methyl benzoates complexed with Cr(C0)3

Journal of Organometallic Chemistry ◽

10.1016/s0022-328x(00)98068-9 ◽

1977 ◽

Vol 127 (3) ◽

pp. 315-324 ◽

Cited By ~ 7

Author(s):

A Ceccon ◽

M Gentiloni ◽

A Romanin ◽

A Venzo

Keyword(s):

Substituent Effects ◽

Polarographic Reduction ◽

Phenyl Ketones

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ChemInform Abstract: SUBSTITUENT EFFECTS ON POLAROGRAPHIC REDUCTION OF SOME PHOTOGRAPHIC COLOR INTERMEDIATES

Chemischer Informationsdienst ◽

10.1002/chin.197632074 ◽

1976 ◽

Vol 7 (32) ◽

pp. no-no

Author(s):

AHMAD S. SHAWALI ◽

BAHGAT E. EL-ANADOULI

Keyword(s):

Substituent Effects ◽

Polarographic Reduction

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Substituent effects on electroreduction of the carbon-halogen bond

Australian Journal of Chemistry ◽

10.1071/ch9812331 ◽

1981 ◽

Vol 34 (11) ◽

pp. 2331 ◽

Cited By ~ 1

Author(s):

RS Abeywickrema ◽

EW Della

Keyword(s):

Reduction Potential ◽

Halogen Bond ◽

Substituent Effects ◽

High Yield ◽

Polarographic Reduction ◽

Electric Field Effects ◽

Controlled Potential Electrolysis ◽

Half Wave ◽

Controlled Potential ◽

Substituted 1

Polarographic reduction of a series of 4-substituted 1-iodobicyclo[2,2,2]octanes has been examined in an attempt to assess the effect of substituents on the half-wave reduction potential. It is found that the values of E� do not show a linear correlation with the relevant σ1 constants; the deviations are discussed in terms of the relative importance of the steric and electric field effects of the substituent. Controlled-potential electrolysis of a number of the substrates reveals that the hydrocarbon corresponding to fission of the carbon-iodine bond is formed in high yield.

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