Results 251 to 260 of about 60,540 (292)
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Substituent effects in cyclohexenes
Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1980The effects of the C1-CH3 group in the13C spectra of trans-4,5-dimethylcyclohex-4-ene-1,2-dicarboxylic and syn-txans-Δ4-octalin-1,2-dicarboxylic acid and their diesters show the existence in solution of a considerable proportion of the trans-a,a forms of these compounds.
V. A. Denisenko +3 more
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Substituent effects in the napthalene system. [PDF]
Forty-four substituted 2-naphthoic acids, two substituted 1-naphthoic acids and some of their corresponding methyl esters have been synthesized. The substituents are the nitro, cyano, fluoro, chloro, bromo, iodo, methyl, hydroxyl, methoxy, amino and dimethylamino groups.
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Collection of Czechoslovak Chemical Communications, 1980
Various quantum chemical approaches to the problem of transmission of the substituent effect were compared. It was shown that inclusion of the electronic repulsion (field effect) was necessary to give a true picture of differences in ρ constants for reactions of the cis and trans isomers of substituted unsaturated carboxylic acids; the same holds for ...
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Various quantum chemical approaches to the problem of transmission of the substituent effect were compared. It was shown that inclusion of the electronic repulsion (field effect) was necessary to give a true picture of differences in ρ constants for reactions of the cis and trans isomers of substituted unsaturated carboxylic acids; the same holds for ...
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Substituent effects in cyclopolyphosphines
Journal of the Chemical Society, Chemical Communications, 1974For cyclopolyphosphines, (RP)n, a linear relationship which is independent of the ring size, n, exists between the electrochemical reduction potential of the ring and the inductive effect of the pendant organic group.
Timothy J. DuPont +2 more
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Additive Effects of Substituents
Nature, 1950THE present practice of analysing data relating to reaction-rates in solution in terms of the parameters of the modified Arrhenius equation, has led to a more complete understanding of the way in which polar substituents affect chemical reactivity by focusing attention on the fact
BRYNMOR JONES, J. ROBINSON
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Journal of Physical Organic Chemistry, 1999
A brief description and analysis of the history of and modern situation in the field of inductive effects, methods for its quantitative determination and prospects are presented, including a discussion of the underlying mechanism. Copyright © 1999 John Wiley & Sons, Ltd.
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A brief description and analysis of the history of and modern situation in the field of inductive effects, methods for its quantitative determination and prospects are presented, including a discussion of the underlying mechanism. Copyright © 1999 John Wiley & Sons, Ltd.
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Substituent effects on the redox reactions of tetraphenylporphyrins
Bioinorganic Chemistry, 1977The effect of substituents on pi radical reactions of para-substituted tetraphenylporphyrins was investigated by cyclic voltammetry in methylene chloride. In all cases electron donating substituents produced a more difficult reduction and an easier oxidation. Plots of E1/2 vs.
K M, Kadish, M M, Morrison
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Substituent effects on aromatic stacking interactions
Organic & Biomolecular Chemistry, 2007Synthetic supramolecular zipper complexes have been used to quantify substituent effects on the free energies of aromatic stacking interactions. The conformational properties of the complexes have been characterised using NMR spectroscopy in CDCl(3), and by comparison with the solid state structures of model compounds.
COCKROFT SL +9 more
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Substituent effects on the electronic structure of siloles
Chemical Communications, 2009Siloles are attractive building blocks for the design and synthesis of organic semiconductors that exhibit potential applications in light-emitting diodes, solar cells, field-effect transistors, and sensors. Understanding how molecular engineering of the electronic structures can help control the properties of these materials has attracted significant ...
Xiaowei, Zhan +2 more
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Substituent effect of benzaldehydes on tyrosinase inhibition
Plant Physiology and Biochemistry, 2017Benzaldehyde inhibited the oxidation of 4-t-butylcatechol catalyzed by mushroom tyrosinase with an IC50 of 31.0 μM. The inhibition kinetics analyzed by Dixon plot indicated that it acts as a partial noncompetitive inhibitor. Further studies of several benzaldehydes, particularly those having a substitution at C-4, suggested that the partial inhibitory ...
Ken-ichi Nihei, Isao Kubo
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