Carboxylate anion, basicity electron withdrawal

Phenols that bear strongly electron withdrawing substituents usually give low yields of carboxylated products their derived phenoxide anions are less basic and the equilibrium constants for their carboxylation are smaller... 

The kinds of vinyl monomers which undergo anionic polymerization are those with electron-withdrawing substituents such as the nitrile, carboxyl, and phenyl groups. We represent the catalysts as AB in this discussion these are substances which break into a cation (A ) and an anion (B ) under the conditions of the reaction. In anionic polymerization it is the basic anion which adds across the double bond of the monomer to form the active center for polymerization ... 

We can appreciate that ionization of the carboxylie acid is affected by the electron-withdrawing inductive effect of the ammonium residue hence the increased acidity when compared with an alkanoic acid. Similarly, loss of a proton from the ammonium cation of the zwitterion is influenced by the electron-donating inductive effect from the carboxylate anion, which should make the amino group more basic than a typical amine. That this is not the case is thought to be a solvation effect (compare simple amines). 

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