How Are Carboxylic Acids Named

Dicarboxylic acids are named by adding the suffix -dioic, followed by the word o/dd, to the name of the carbon chain that contains both carboxyl groups. Because the two carboxyl groups can be only at the ends of the parent chain, there is no need to number them. Following are lUPAC names and common names for several important aliphatic dicarboxylic acids  

The name oxalic acid is derived from one of its sources in the biological world, namely, plants of the genus Oxalis, one of which is rhubarb. Oxalic acid also occurs in human and animal urine, and calcium oxalate (the calcium salt of oxalic acid) is a major component of kidney stones. Adipic acid is one of the two monomers required for the synthesis of the polymer nylon 66. The U.S. chemical industry produces approximately 1.8 billion pounds of adipic acid annually, solely for the synthesis of nylon 66 (Section 16.4A). 

Leaves of the rhubarb plant contain oxalic acid as its potassium and sodium salts. 

The simplest aromatic carboxylic acid is benzoic acid. Derivatives are named by using numbers and prefixes to show the presence and location of substituents relative to the carboxyl group. Certain aromatic carboxylic acids have common names by which they are more usually known. For example, 2-hydroxybenzoic acid is more often called salicylic acid, a name derived from the fact that this aromatic carboxylic acid was finst obtained from the bark of the willow, a tree of the genus SaEx. Aromatic dicarboxylic acids are named by adding the words dicarboxylic acid to benzene. Examples are 1,2-benzenedicarboxyhc acid and 1,4-benzenedicar-boxylic acid. Each is more usually known by its common name phthahc acid and terephthalic acid, respectively. Terephthahc acid is one of the two organic components required for the synthesis of the textile fiber known as Dacron polyester (Section 16.4B). 

Benzoic acid 2-Hydroxybenzoic acid (Salicylic acid) 

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