Concept explainers
The Enolate Chemistry of Dianionss
The synthetic applications of carbanions as reagents for carbon
Consider acetic acid:
The pKa of acetic acid is
for ionization of a
is shared by carbon. The dianion, however, has carbanionic character and the potential to act as a
nucleophile in carbon
Diisopropylamine has a pKa of
enough base to convert acetic acid to its dianion. Other carboxylic acids behave similarly to give
dianions that undergo typical carbanion reactions. Alkylation of
Experimentally, as in this example, it is sometimes useful to convert the carboxylic acid to its carboxylate (monoanion) with sodium hydride (NaH, step
The dianions of α-halocarboxylic acids give epoxy acids (called glycidic acids) on reaction with
Dianions have been prepared from
Protons on the
What is the product of the reaction of the dianion in Problem
Predict the major organic product(s) of the following reaction
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