Basic Organic Nomenclature

Carboxylic Acid Derivatives - Acyl Halides

Suffix:    -oyl halide

Prefix:    halidealkanoyl-

The second derivative of carboxylic acids is generated by replacing the -OH of the acid with a halide atom. Similar to acids and amides, the carbon atom of the acyl halide will be atom number 1 in the numbering scheme. Since it always occurs at the end(s) of the chain of carbon atoms, the number is omitted. In naming the acyl halide, the final -e of the alkane is replaced by -oyl halide. The general formula for an amide is CnH2nOX (where X is; F, Cl, Br, I). Acyl halides are man made, and the most commonly used is the acyl chloride.

Examples naming simple acyl chlorides:

Compound Name
Line Drawing
3D Model
methanoyl chloride
ethanoyl chloride
 propanoyl chloride
2-methylpropanoyl chloride

Examples naming more complex acyl halides:

Compound Name
Line Drawing
2-hydroxypropanoyl chloride
5,5-dimethyl-3-oxohexanoyl chloride
 4-amino-6-heptenoyl chloride

Acyl halides as Substituents:

In more complex molecules with higher priority functional groups, the acyl halide is named as a halidealkanoyl- substituent. It is located by numbering the longest chain of carbons (according to the higher priority functional group) and locating the -COCl group by this numbering scheme.

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