Titlebook: pKa Prediction for Organic Acids and Bases; D. D. Perrin,Boyd Dempsey,E. P. Serjeant Book 1981 D. D. Perrin, Boyd Dempsey and E. P. Serjea

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Molecular Factors that Modify p,, Values,is acid-strengthening or base-weakening. Consideration of factors that modify the relative stabilities of these species can thus provide insights as to why p.. values vary but they do not permit calculations of the differences involved. It is nonetheless, useful to have even a qualitative indication of how substituents affect p.. values.

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Introduction,as ionization constants and on the reactivities of organic molecules. As a result it is now possible to predict to within several tenths of a pH unit many of the p.. values which express the strengths of organic acids and bases. This book seeks to provide guidelines to enable such predictions to be

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Further Applications of Hammett and Taft Equations,ess 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 field effect than would be exerted by the same substituent attached at the free end of a chain, and m

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Extension of the Hammett and Taft Equations,ples. It has been found empirically (Jaffé, 1953) that as a working approximation the hetero group (— O —, — S —, — NH —) in an unsaturated 5-membered ring carrying an acidic or basic group can be replaced by — C(— OR, — SR, —NHR) = CH —, respectively, giving a benzene derivative. An acidic or basic

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