9.1 Amides, Esters, and Anhydrides

LEARNING GOALS

After   Chapter 9.1,    you will    be  able    to:

Apply   the rules   for naming  carboxylic  acid    derivatives,    including   the nomenclature    for the

cyclic  version of  the molecule

Describe    a   condensation    reaction

Amides, esters, and anhydrides are all carboxylic acid derivatives. Each of these is formed by a
condensation reaction with a carboxylic acid—a reaction that combines two molecules into one,
while losing a small molecule. In this case, the small molecule is water, which is created from the
hydroxyl group of the carboxylic acid and a hydrogen associated with the incoming nucleophile.

KEY CONCEPT

In  a   condensation    reaction,   two molecules   are combined    to  form    one,    with    the loss    of  a

small   molecule—water, in  our case.   Carboxylic  acid    derivatives are formed  by  this

mechanism.

DESCRIPTIONS

For each of the carboxylic acid derivatives described in this section, focus on the relevant
nucleophile that forms the derivative and the nomenclature of the functional group. In the next
section, we’ll focus more directly on the relative reactivity of these compounds.