91 Unit 13: Carboxylic acid derivatives
The carboxyl group (abbreviated -CO 2 H or -COOH) is one of the most widely occurring
functional groups in chemistry as well as biochemistry. The carboxyl group of a large family
of related compounds called Acyl compounds orCarboxylic Acid Derivatives.
All the reactions and compounds covered in this section will yield Carboxylic Acids on
hydrolysis, and thus are known as Carboxylic Acid Derivatives. Hydrolysis is one example
ofNucleophilic Acyl Substitution, which is a very important two step mechanism that is
common in all reactions that will be covered here.
91.1 Structure
This group of compounds also contains a carbonyl group, but now there is an electronegative
atom (oxygen, nitrogen, or a halogen) attached to the carbonyl carbon. This difference in
structure leads to a major change in reactivity.
91.2 Nomenclature.
The systematic IUPAC nomenclature for carboxylic acid derivatives is different for the
various compounds which are in this vast category, but each is based upon the name of the
carboxylic acid closest to the derivative in structure. Each type is discussed individually
below.
91.2.1 Acyl Groups
Acyl groups are named by stripping the-ic acidof the corresponding carboxylic acid and
replacing it with-yl.
EXAMPLE:
CH 3 COOH =acetic acidCH 3 COO-R =acetyl-R91.2.2 Acyl Halides
Simply add the name of the attached halide to the end of the acyl group.