Functional Classes I, Structure and Naming - Organic Chemistry Concepts: An EFL Approach - page 33

2.8.3 Carboxylic Acid (Acyl) Derivatives
The classes of carboxylic acid derivatives are also modifications of the carbonyl
functional group. All of them have the common R-CO- acyl fragment. These
fragments are made up of any carbon group attached to a carbonyl group.
Because of their chemical relationships as seen in Table 2.15 , they are seen as
derivatives of carboxylic acids.

Table 2.15 Some Common Acyl Root Names
Parent Acid Acyl Group Name

HCO 2 H HCO- Formyl (methanoyl)

CH 3 CO 2 H CH 3 CO- Acetyl (ethanoyl)

CH 3 CH 2 CO 2 H CH 3 CH 2 CO- Propanoyl

CH 2 ] CHCO 2 H CH 2 ] CHCO- Acryloyl (propenoyl)

Benzoyl

Like acids, the carbon of the functional group has three bonds to heteroatoms
and a nominal oxidation number of +3. Carboxylic acids can be seen as an
alcohol hydroxyl group modified by the carbonyl function. Table 2.16 shows
that acyl halides, esters, and amides are carbonyl modified versions of organic
halides, ethers, and amines.

Table 2.16 Selected Acyl-Based Compounds
Acyl Compound

Name

CH 3 COCl Acetyl (ethanoyl) chloride

Benzoyl chloride

CH 3 CO 2 CH 2 CH 3 Ethyl acetate (ethanoate)

CH 2 ] CHCO 2 CH 3 Methyl acrylate (propenoate)

CH 3 (CH 2 ) 4 CONH 2 Hexanamide

Cyclopentanecarboxamide

CH 3 CH 2 CONHCH 3 N -Methylpropanamide

CH 3 CO-O-COCH 3 Acetic (ethanoic) anhydride

Benzoic anhydride