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Multiparameter Extensions of the Hammett Equation
1978The Hammett equation (1937)2,3,4 takes forms (4.1), (4.2), where k or K is the rate or equilibrium constant for a side-chain reaction of a meta- or $$\log k^0 = \log k^0 + \rho \sigma $$ (4.1) $$\log K^0 = \log K^0 + \rho \sigma $$ (4.2) para-substituted benzene derivative.
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Applications of the Hammett Equation to Heterocyclic Compounds
1964Publisher Summary The Hammett equation is one of the most widely applied relations between the structure and reactivity of organic compounds. This equation relates the relative reactivities of the series of di- and poly-substituted benzene derivatives.
H.H. Jaffe, H. Lloyd Jones
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Applications of the Hammett Equation to Heterocyclic Compounds
1976Publisher Summary This chapter describes the applicability of Hammett-type parameters that may be tested for heterocyclic compounds in a number of different ways. Work on specific heterocyclic systems may be grouped under two headings: The ring heteroatom as a substituent and reactivity of heteroatoms, as affected by other substituents.
P. Tomasik, C.D. Johnson
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Theoretical considerations concerning the hammett equation — VIII
Tetrahedron, 1963Abstract The resonance contribution, PR, to Hammett p values, and the Taft-Lewis parameter α have been calculated for five aromatic oxygen acids. The method of calculation consisted of a crude calculation by the LCAO MO method of the changes of charge distribution in an acid molecule effected by a substituent, and an assessment of the effect of this ...
J.L. Roberts, H.H. Jaffé
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Further Applications of Hammett and Taft Equations
1981The success of the method of prediction based on the additivity of increments of pK a values along chains in a molecule is not evidence of the correctness of the assumption that inductive effects are of overriding importance. Ring formation, by constraining the substituent in much closer proximity to the acidic or basic centre, leads to a stronger ...
D. D. Perrin +2 more
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APPLICATION OF THE HAMMETT EQUATION TO THE HYDROLYSIS OF SUBSTITUTED BENZAMIDES
Canadian Journal of Chemistry, 1960not available
J. T. Edward +3 more
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An application of the hammett equation to the cathodic reduction of aromatic acids
Electrochimica Acta, 1976Abstract Nine aromatic acids were cathodically reduced in aqueous acid medium. Lead was the main cathode metal employed, though experiments on Cu, Fe, Cd, Sn and Cu/Hg as well as PbSn alloys are also reported. At all potentials, hydrogen evolution was the dominant electrode reaction.
M.D. Birkett, A.T. Kuhn
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The Hammett Equation—the Present Position
1972This chapter represents—in a certain sense—the introduction to the whole book, since the Hammett equation is the oldest and most developed empirical relationship, and many general features can be demonstrated by using it as the only available example. For this reason this chapter will deal with the Hammett equation in a broad sense and many statements ...
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ChemInform Abstract: The Prehistory of the Hammett Equation
ChemInform, 2000AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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A note on the extended Hammett equation for radical reactions
Tetrahedron, 1972Abstract A critical examination of the extended Hammett equations proposed for radical reactions is presented. It is shown that the resonance parameters are in error and that the use of these relations may bring about false conclusions concerning the mechanism of the reaction studied.
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