Infrared spectra of aqueous sodium benzoates and salicylates in the carboxyl-stretching region: chelation in aqueous sodium salicylates

1969 ◽  
Vol 47 (24) ◽  
pp. 4577-4588 ◽  
Author(s):  
G. E. Dunn ◽  
R. S. McDonald
Keyword(s):  
Salicylic Acid ◽  
Carbon Tetrachloride ◽  
Infrared Spectra ◽  
Aromatic Compounds ◽  
Deuterium Oxide ◽  
Substituent Effects ◽  
Good Evidence ◽  
Frequency Region ◽  
Aqueous Sodium ◽  
Substituent Constants

Infrared spectra in the frequency region 1300–1760 cm−1 are reported for 41 substituted sodium benzoates and 10 substituted sodium salicylates in deuterium oxide solution, and for 9 substituted salicylic acids in chloroform and carbon tetrachloride solutions. Carboxylate stretching frequencies of benzoates and salicylates correlate poorly with substituent constants, but the asymmetric frequencies of benzoates and salicylates correlate well with each other, and the asymmetric frequencies of benzoates correlate well with the asymmetric frequencies of the corresponding nitrobenzenes. It is suggested that, among substituted aromatic compounds, group vibrations which couple with the ring vibrations may correlate well with similar vibrations of other groups, but not with coupled vibrations of different symmetry, uncoupled vibrations, or substituent constants. Chelation in chloroform solutions of salicylic acid dimers can be detected by its influence on substituent effects, but infrared spectra provide no good evidence for chelation in aqueous sodium salicylates.

The SN Mechanism in aromatic compounds. 25. Substituent effects of multiple-bond nitrogen.

1958 ◽  
Vol 11 (3) ◽  
pp. 302 ◽  
Author(s):  
J Miller ◽  
AJ Parker
Keyword(s):  
Double Bond ◽  
Nitrogen Atom ◽  
Nucleophilic Substitution ◽  
Benzene Ring ◽  
Aromatic Compounds ◽  
Halogen Atom ◽  
Multiple Bond ◽  
Substituent Effects ◽  
Aromatic Nucleophilic Substitution ◽  
Substituent Constants

The substituent effects in aromatic nucleophilic substitution of groups attached to the benzene ring by a multiple-bond nitrogen atom are considered. Attachment is para to a replaceable halogen atom, and generally as a 4-substituent to l-chloro-2-nitrobenzene. Comparisons with some other groups are shown. Reasons are given for the greater T effect of a triple than of a double bond. Hammett substituent constants (σ*) are computed. Those for the nitroso and diazonium groups .are the largest so far obtained for electrically neutral and cationic groups respectively. The activating power of four of the nitrogen groups in electrophilic as well as nucleophilic substitution is discussed briefly.

Substituent effects in 1,3-indanediones

1982 ◽  
Vol 47 (5) ◽  
pp. 1486-1493 ◽  
Author(s):  
Alexander Perjéssy
Keyword(s):  
Substituent Effects ◽  
Empirical Equations ◽  
Substituent Constants ◽  
Complex Structural

The carbonyl stretching frequencies correlate well with substituent constants in a series of 166 1,3-indanediones using improved and extended Seth-Paul-Van Duyse equation. Transmissive factors and group electronegativities have been used to find empirical equations for calculation of substituent constants of more complex structural fragments.

Kinetic Study of Hydrolysis of Benzoates. Part XXVI. Variation of the Substituent Effect with Solvent in Alkaline Hydrolysis of Substituted Alkyl Benzoates

2006 ◽  
Vol 71 (11-12) ◽  
pp. 1557-1570 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Ilmar A. Koppel
Keyword(s):  
Kinetic Study ◽  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Substituent Effect ◽  
Substituent Effects ◽  
Alkyl Substituent ◽  
Solvent Parameters ◽  
Substituent Constants ◽  
Hydrolysis Of ◽  
Main Factor

The second-order rate constants k2 (dm3 mol-1 s-1) for the alkaline hydrolysis of substituted alkyl benzoates C6H5CO2R have been measured spectrophotometrically in aqueous 0.5 M Bu4NBr at 50 and 25 °C (R = CH3, CH2Cl, CH2CN, CH2C≡CH, CH2C6H5, CH2CH2Cl, CH2CH2OCH3, CH2CH3) and in aqueous 5.3 M NaClO4 at 25 °C (R = CH3, CH2Cl, CH2CN, CH2C≡CH). The dependence of the alkyl substituent effects on different solvent parameters was studied using the following equations:      ∆ log k = c0 + c1σI + c2EsB + c3∆E + c4∆Y + c5∆P + c6∆EσI + c7∆YσI + c8∆PσI     ∆ log k = c0 + c1σ* + c2EsB + c3∆E + c4∆Y + c5∆P + c6∆Eσ* + c7∆Yσ* + c8∆Pσ* .  ∆ log k = log kR - log kCH3. σI and σ* are the Taft inductive and polar substituent constants. E, Y and P are the solvent electrophilicity, polarity and polarizability parameters, respectively. In the data treatment ∆E = ES - EH2O , ∆Y = YS - YH2O , ∆P = PS - PH2O were used. The solvent electrophilicity, E, was found to be the main factor responsible for changes in alkyl substituent effects with medium. When σI constants were used, variation of the polar term of alkyl substituents with the solvent electrophilicity E was found to be similar to that observed earlier for meta and para substituents, but twice less when σ* constants were used. The steric term for alkyl substituents was approximately independent of the solvent parameters.

Effects of Medium and Substituents on Dissociationof 4,4'-Disubstituted Bis(benzenesulfon)imides

1996 ◽  
Vol 61 (8) ◽  
pp. 1205-1214 ◽  
Author(s):  
Miroslav Ludwig ◽  
Pavel Štverka
Keyword(s):  
Latent Variables ◽  
Dissociation Constants ◽  
Substituent Effects ◽  
Principal Component ◽  
H Nmr ◽  
Base Process ◽  
Elemental Analyses ◽  
Substituent Constants ◽  
Model Substances ◽  
Strong Acids

Ten 4,4'-disubstituted bis(arenesulfon)imides of the general formula XC6H4SO2NHSO2C6H4X have been synthesized and their structures confirmed by their 1H NMR spectra. Elemental analyses are presented for the compounds not yet described. The dissociation constants of these model substances have been measured potentiometrically in pyridine, dimethylformamide, methanol, ethanol, propylene carbonate, acetone, acetonitrile, 1,2-dichloroethane and tetramethylene sulfone. The pKHA values obtained have been correlated with three sets of the Hammett substituent constants and the results have been used to discuss the solvent and substituent effects on the dissociation of the compounds studied. Sulfonimides with electron-acceptor substituents behave as rather strong acids in some solvents (pyridine, dimethylformamide, methanol and ethanol), whereas normal substituent dependences are found in other solvents. The experimental data have also been interpreted with the help of the statistical methods based on latent variables. From the calculations it follows that only the first principal component, which correlates well with the substituent constant sets adopted, is statistically significant in describing the substituent effect on the acid-base process studied.

Theoretical modeling of infrared spectra of hydrogen-bonded crystals of salicylic acid

2006 ◽  
Vol 64 (3) ◽  
pp. 757-760 ◽  
Author(s):  
Marek Boczar ◽  
Łukasz Boda ◽  
Marek J. Wójcik
Keyword(s):  
Salicylic Acid ◽  
Infrared Spectra ◽  
Theoretical Modeling ◽  
Hydrogen Bonded

scholarly journals Infrared spectra of some aromatic compounds

1953 ◽  
Author(s):  
Marvin Margoshes
Keyword(s):  
Infrared Spectra ◽  
Aromatic Compounds

scholarly journals THE USE OF INFRARED SPECTROPHOTOMETRY FOR THE ESTIMATION OF SMALL QUANTITIES OF SOME HALOGENATED HYDROCARBONS

1953 ◽  
Vol 31 (4) ◽  
pp. 328-337 ◽  
Author(s):  
L. Breitman ◽  
E. W. R. Steacie
Keyword(s):  
Quantitative Analysis ◽  
Carbon Tetrachloride ◽  
Gas Phase ◽  
Infrared Spectra ◽  
Methyl Chloride ◽  
Ternary Mixtures ◽  
Halogenated Hydrocarbons ◽  
Infrared Spectrophotometry ◽  
Absorption Bands ◽  
Binary And Ternary Mixtures

The infrared spectra of chloral, carbon tetrachloride, and chloroform have been determined between 1500 and 650 cm.−1 over a range of pressures in the gas phase. Absorption bands suitable for the quantitative analysis of binary and ternary mixtures of the components have been selected and their peak intensities shown to obey Beer's Law over the range of pressures studied. Ternary mixtures have been analyzed from the spectra with an accuracy of about 20%.The spectra of dichloromethane and methyl chloride have also been measured under comparable conditions.

PHOTOCHEMICAL INTERCHANGE OF HALOGENS IN AROMATIC COMPOUNDS. II. TEMPERATURE DEPENDENCE OF SOME SUBSTITUENT EFFECTS

1962 ◽  
Vol 66 (11) ◽  
pp. 2118-2120 ◽  
Author(s):  
Barton Milligan ◽  
Ronald L. Bradow
Keyword(s):  
Temperature Dependence ◽  
Aromatic Compounds ◽  
Substituent Effects
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