THE INHIBITED AUTOXIDATION OF STYRENE: PART II. THE RELATIVE INHIBITING EFFICIENCIES OF META- AND PARA-SUBSTITUTED PHENOLS

1963 ◽  
Vol 41 (7) ◽  
pp. 1744-1751 ◽  
Author(s):  
J. A. Howard ◽  
K. U. Ingold
Keyword(s):  
Hydrogen Abstraction ◽  
Excellent Correlation ◽  
Substituted Phenols ◽  
Substituent Constants

The relative rates of reaction of 11 meta- and para-substituted phenols with styrylperoxy radicals have been measured at 65 °C and have been shown to give an excellent correlation with electrophilic substituent constants. The reaction is compared with a number of similar hydrogen abstraction reactions.

The application of the Hammett equation to 13C N.M.R. spectroscopy: correlations in the β-nitrostyrenes

1976 ◽  
Vol 29 (12) ◽  
pp. 2607 ◽  
Author(s):  
DAR Happer
Keyword(s):  
Chemical Shift ◽  
Convenient Method ◽  
Experimental Error ◽  
Dimethyl Sulphoxide ◽  
Hammett Equation ◽  
Excellent Correlation ◽  
Substituent Constants ◽  
Hammett Σ Constants

A series of 33 β-nitrostyrenes has been prepared and their 13C N.M.R. spectra have been determined in dimethyl sulphoxide and in deuterochloroform (where soluble). Hammett correlations between substituent and the chemical shift of both the para ring carbons and the α-carbon of the ethenyl group have been shown to be only approximate. In contrast, an excellent correlation has been observed between the chemical shift of the β-carbon of the ethenyl group and Hammett σ+ constants in all cases except those involving para substituents capable of exerting a - R effect. Possible reasons for this are considered. The system appears to be the first reported one where 13C measurements for both meta- and para-substituted compounds give rise to correlations in which agreement lies well inside the limits of experimental error, and shows promise as a convenient method for calculating substituent constants and studying their variation with solvent.

THE EFFECT OF SUBSTITUENTS ON THE RELATIVE RATES OF REACTION OF tert-BUTOXY RADICALS WITH PHENOLS IN CARBON TETRACHLORIDE AND IN CHLOROBENZENE

1963 ◽  
Vol 41 (11) ◽  
pp. 2816-2825 ◽  
Author(s):  
K. U. Ingold
Keyword(s):  
Carbon Tetrachloride ◽  
Transition State ◽  
Hydrogen Abstraction ◽  
Substituted Phenols ◽  
Aromatic Solvent ◽  
Effect Of Substituents

The relative rates of hydrogen abstraction from substituted phenols by t-butoxy radicals can be correlated with the σ+ constants of the substituents. The effects of an aromatic solvent (chlorobenzene) and of ortho-alkyl substituents on the reactivities of the phenols and on the transition state of the reaction are discussed.

Theoretical Study of the Hydrogen Abstraction of Substituted Phenols by Nitrogen Dioxide as a Source of HONO

2014 ◽  
Vol 118 (46) ◽  
pp. 11002-11014 ◽  
Author(s):  
Abraham Shenghur ◽  
Kevin H. Weber ◽  
Nhan D. Nguyen ◽  
Watit Sontising ◽  
Fu-Ming Tao
Keyword(s):  
Nitrogen Dioxide ◽  
Theoretical Study ◽  
Hydrogen Abstraction ◽  
Substituted Phenols

Absolute rate constants for hydrocarbon oxidation. VIII. The reactions of cumylperoxy radicals

1968 ◽  
Vol 46 (6) ◽  
pp. 1017-1022 ◽  
Author(s):  
J. A. Howard ◽  
K. U. Ingold ◽  
M. Symonds
Keyword(s):  
Rate Constants ◽  
Isotope Effects ◽  
Hydrogen Abstraction ◽  
Cumene Hydroperoxide ◽  
Hydrogen Atom Abstraction ◽  
Hydrocarbon Oxidation ◽  
Peroxy Radicals ◽  
Absolute Rate ◽  
Substituent Constants ◽  
Deuterium Isotope Effects

Absolute rate constants have been measured for the reactions of cumylperoxy radicals with a number of hydrocarbons. The cumylperoxy radicals were produced from cumene hydroperoxide. Sufficient hydroperoxide was present to ensure that only cumylperoxy radicals were involved in the rate-determining propagation reaction.Primary and secondary deuterium isotope effects have been measured for propagation and termination in the oxidation of cumene. The rate of hydrogen atom abstraction from ring-substituted cumenes by cumylperoxy radicals can be correlated by the Hammett equation using σ+ substituent constants, ρ = −0.29. Primary and secondary peroxy radicals are about 3–5 times more reactive in hydrogen abstraction than tertiary peroxy radicals.

scholarly journals Excellent correlation between substituent constants and pyridinium N-methyl chemical shifts

2009 ◽  
Vol 50 (35) ◽  
pp. 5018-5020 ◽  
Author(s):  
Sha Huang ◽  
Jesse C.S. Wong ◽  
Adam K.C. Leung ◽  
Yee Man Chan ◽  
Lili Wong ◽  
...  
Keyword(s):  
Chemical Shifts ◽  
Excellent Correlation ◽  
Substituent Constants

Substituent and Solvent Effects on the Electrochemical Oxidation of para- and meta-Substituted Anilines

2006 ◽  
Vol 61 (10) ◽  
pp. 1254-1260 ◽  
Author(s):  
Durvas S. Bhuvaneshwari ◽  
Kuppanagounder P. Elango
Keyword(s):  
Electrochemical Oxidation ◽  
Supporting Electrolyte ◽  
Oxidation Potential ◽  
Negative Reaction ◽  
Excellent Correlation ◽  
Multiple Correlation ◽  
Substituted Anilines ◽  
Multiple Correlation Analysis ◽  
Substituent Constants ◽  
Reaction Constants

Electrochemical oxidation of fifteen para- and meta-substituted anilines in different mole fractions of acetic acid in water has been investigated in the presence of 0.1 M sulphuric acid as supporting electrolyte. The oxidation potential data of anilines correlates well with Hammett’s and Brown- Okamoto’s substituent constants affording negative reaction constants. The effect of para- and metasubstituents on the oxidation potential conforms to Swain’s F and R parameters, affording negative reaction constants. The oxidation potential values correlate well with macroscopic solvent parameters such as relative permittivity, εr, and polarity, ETN. Multiple correlation analysis also shows an excellent correlation with the oxidation potential values.

New method for the determination of permeation coefficients of functional chemical groups using membrane model vesicles

1989 ◽  
Vol 67 (10) ◽  
pp. 1606-1608
Author(s):  
Jean-Louis Kraus ◽  
Sophie Micheau ◽  
Philippe Pernice ◽  
Madeleine Castaing
Keyword(s):  
Partition Coefficients ◽  
Water System ◽  
Quantitative Structure Activity Relationship ◽  
Membrane Model ◽  
Excellent Correlation ◽  
Hydrophobic Properties ◽  
Structure Activity ◽  
Substituent Constants ◽  
Chemical Groups

New substituent constants πp, derived from permeation coefficients, of membrane model vesicles have been evaluated for fifteen functional groups. The excellent correlation found between the new substituent constants and the values derived from partition coefficients in octanol–water system leads one to consider this new parameter and the technique used for its evaluation as new promising tools for quantitative structure–activity relationship studies and for hydrophobic properties measurement. Keywords: permeation coefficients, model membrane, dihexadecyl-phosphate vesicles.

Separation of close boiling substituted phenols by dissociation extraction

1981 ◽  
Vol 31 (1) ◽  
pp. 279-284 ◽  
Author(s):  
Vishwas V. Wadekar ◽  
Man Mohan Sharma
Keyword(s):  
Substituted Phenols

A novel method for the determination of linting propensity of paper

TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD
Keyword(s):  
Ash Content ◽  
The Novel ◽  
Offset Printing ◽  
Excellent Correlation ◽  
End Conditions ◽  
Bottom Side ◽  
Novel Method ◽  
Total Fraction

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.

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