The transmission of polar effects. Part IX. The ionization and esterification with diazodiphenylmethane of 9-substituted 10-triptoic acids

1969 ◽  
Vol 47 (2) ◽  
pp. 177-183 ◽  
Author(s):  
Keith Bowden ◽  
D. C. Parkin
Keyword(s):  
Free Energy ◽  
Field Effect ◽  
Inductive Effect ◽  
Rate Coefficients ◽  
Linear Free Energy ◽  
Effect Model ◽  
Energy Relations

A series of 9-substituted 10-triptoic acids have been prepared. Their pKa values in 80% 2-methoxy-ethanol–water and 50% ethanol–water at 25° and rate coefficients for esterification with diazodiphenyl-methane in five alcohols at 30° have been measured. The results have been analyzed by linear free energy relations. The π-inductive effect is shown to be unimportant in such systems, while the field effect model can account for the transmission.

The transmission of polar effects. Part X. The esterification with diazodiphenyl-methane and the ionization of 9-substituted 10-anthroic and 8-substituted 1-naphthoic acids

1969 ◽  
Vol 47 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Keith Bowden ◽  
D. C. Parkin
Keyword(s):  
Free Energy ◽  
Ethyl Acetate ◽  
Field Effect ◽  
Isopropyl Alcohol ◽  
Substituent Effects ◽  
Butyl Alcohol ◽  
Rate Coefficients ◽  
Linear Free Energy ◽  
Energy Relations ◽  
Substituted 1

The rate coefficients for the reaction with diazodiphenylmethane in methanol, ethanol, isopropyl alcohol, t-butyl alcohol, 2-methoxyethanol, 2-n-butoxyethanol, and ethyl acetate at 30° and the pKa values in 80% 2-n-butoxyethanol–water of a series of 9-substituted 10-anthroic and 8-substituted 1-naphthoic acids have been determined. The effect of substitution has been analyzed by linear free energy relations. The variation in the susceptibilities of the systems to polar substituent effects with the medium are examined. The occurrence of reversed dipolar substituent effects in the reactions of the 1,8-naphthoic acids is detected. The implications of the results for the inductive and field effect models for the transmission of polar effects are discussed.

The transmission of polar effects. Part VII. A proton magnetic resonance spectra study of substituted mesitylenes, durenes, anthracenes, and triptycenes

1968 ◽  
Vol 46 (24) ◽  
pp. 3903-3908 ◽  
Author(s):  
Keith Bowden ◽  
J. G. Irving ◽  
M. J. Price
Keyword(s):  
Dielectric Constant ◽  
Free Energy ◽  
Carbon Tetrachloride ◽  
Field Effect ◽  
Proton Magnetic Resonance ◽  
Chemical Shifts ◽  
Linear Free Energy ◽  
Solvent Dependence ◽  
Similar Dependence ◽  
Energy Relations

The chemical shifts of the ring protons in a series of monosubstituted mesitylenes and durenes, and of the 10-protons of a series of 9-substituted triptycenes and anthracenes have been measured in dimethyl sulfoxide, acetone, 2-methoxyethanol, and carbon tetrachloride. The solvent dependence of the substituent chemical shifts has been analyzed by linear free energy relations. The systems all show similar dependence which increases with increasing dielectric constant of the solvent. This does not result from the field effect being transmitted through the medium, but appears to arise from the formation of a hydrogen-bonded interaction between the solvent and the hydrogen of the solute. The substituent chemical shifts appear to arise from contributions from substituent field, resonance, magnetic anisotropy, and solvent effects.

Requirements and interpretation of linear free energy relations

1984 ◽  
Vol 106 (10) ◽  
pp. 2772-2774 ◽  
Author(s):  
Peter E. Doan ◽  
Russell S. Drago
Keyword(s):  
Free Energy ◽  
Linear Free Energy ◽  
Energy Relations

THE TRANSMISSION OF POLAR EFFECTS: PART II. THE KINETICS OF ESTERIFICATION WITH DIAZODIPHENYLMETHANE AND THE IONIZATION OF 3-SUBSTITUTED ACRYLIC ACIDS

1965 ◽  
Vol 43 (12) ◽  
pp. 3354-3363 ◽  
Author(s):  
Keith Bowden
Keyword(s):  
Butyl Alcohol ◽  
Polar Effect ◽  
Rate Coefficients ◽  
Strengthening Effect ◽  
Benzoic Acids ◽  
Linear Free Energy ◽  
Substituted Benzoic Acids ◽  
Energy Relations ◽  
Acrylic Acids ◽  
Kinetics Of

The rate coefficients for the reaction with diazodiphenylmethane in ethanol, t-butyl alcohol, and ethyl acetate at 30° and the pKa values in water at 25° of fourteen 3-substituted acrylic acids have been determined. The effect of substitution is assessed by use of linear free energy relations. A definite incremental acid-strengthening effect solely due to cis-substitution is confirmed. This is not a "bulk" steric effect and is due solely to the orientation of substitution. The polar effect of a substituent is found to be approximately the same from the cis- or trans-position. An attempt is made to test the suggested mechanisms for the transmission of the polar effect. In the reactions studied the transmission of the polar effect in 3-substituted acrylic acid and ortho-substituted benzoic acids is approximately twice that of the meta- or para-substituted benzoic acids. This appears to be reasonably accommodated by a significant field effect.

Linear free energy relations and the hammett equation for substituted pyridine 1-oxides

1967 ◽  
Vol 4 (4) ◽  
pp. 591-597 ◽  
Author(s):  
John H. Nelson ◽  
Roy G. Garvey ◽  
Ronald O. Ragsdale
Keyword(s):  
Free Energy ◽  
Hammett Equation ◽  
Linear Free Energy ◽  
Energy Relations

The reactions of O(3P) with the butanols

1983 ◽  
Vol 61 (12) ◽  
pp. 2716-2720 ◽  
Author(s):  
John M. Roscoe
Keyword(s):  
Free Energy ◽  
Gas Phase ◽  
Rate Constants ◽  
Substrate Concentration ◽  
Kinetic Data ◽  
Absolute Rate ◽  
Gas Phase Reactions ◽  
Linear Free Energy ◽  
Different Types ◽  
Energy Relations

The reactions of O(3P) with the butanols were studied kinetically as a function of temperature and substrate concentration. The absolute rate constants for the gas phase reactions, in the units M−1 s−1, obey the following relations.[Formula: see text]The results suggest that although the α-CH bond in these alcohols is the most reactive one, reaction of O(3P) with other CH bonds in the alcohols is also appreciable. The kinetic data for these and other alcohols are separated into contributions from the different types of CH bonds and the results are discussed in terms of linear free energy relations.

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