An ester is named as alkyl (from the name of the alcohol reactant) carboxylate (from the name of the acid reactant). Alkyl group from alcohol is written first followed by acid component’s stem name with -ate.

the name of the alkyl part of the ester appears first and is alowed by a separate word giving the name for the acyl part of the ester.
the name of the alkyl part of te ester is simply the name of the R group (alkyl, cycloalkyl or aryl group) present.
the name of the acyl part of the ester is obtained by dropping the -ic acid ending fo rthe acid’s name and adding the suffix -ate.

Names of EstersAlthough esters are covalent compounds and salts are ionic, esters are named in a manner similar to that used for naming salts. The group name of the alkyl or aryl portion is given first and is followed by the name of the acid portion. In both common and International Union of Pure and Applied Chemistry (IUPAC) nomenclature, the –ic ending of the parent acid is replaced by the suffix –ate (Table 4.3 “Nomenclature of Esters”).

Table 4.3 Nomenclature of Esters

Example

Draw the structure for ethyl pentanoate.

Solution

Start with the portion from the acid. Draw the pentanoate (five carbon atoms) group first; keeping in mind that the last carbon atom is a part of the carboxyl group.

Then attach the ethyl group to the bond that ordinarily holds the hydrogen atom in the carboxyl group.

Formula of an ester obtained by the reaction of pentanoic acid and ethyl alcohol.

Ethyl Acetate

IN CLASS PRACTICE PROBLEMS:Draw the ester that is formed from the reaction of benzoic acid and ethanol and name the ester.Draw the ester formed by the reaction of heptanoic acid and ethanol.( smells like grapes) and name the esterName the ester below

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Condensed Structural Formula	Common Name	IUPAC Name
HCOOCH₃	methyl formate	methyl methanoate
CH₃COOCH₃	methyl acetate	methyl ethanoate
CH₃COOCH₂CH₃	ethyl acetate	ethyl ethanoate
CH₃CH₂COOCH₂CH₃	ethyl propionate	ethyl propanoate
CH₃CH₂CH₂COOCH(CH₃)₂	isopropyl butyrate	isopropyl butanoatey
	ethyl benzoate	ethyl benzoate