Editing Ester (section)

=== IUPAC nomenclature ===
{{Main|IUPAC nomenclature of organic chemistry#Esters}}
The names of esters that are formed from an alcohol and an acid, are derived from the parent alcohol and the parent acid, where the latter may be organic or inorganic. Esters derived from the simplest [[carboxylic acid]]s are commonly named according to the more traditional, so-called "[[trivial names]]" e.g. as formate, acetate, propionate, and butyrate, as opposed to the IUPAC nomenclature methanoate, ethanoate, propanoate, and butanoate. Esters derived from more complex carboxylic acids are, on the other hand, more frequently named using the systematic IUPAC name, based on the name for the acid followed by the suffix ''-oate''. For example, the ester hexyl octanoate, also known under the trivial name hexyl [[Caprylic acid|caprylate]], has the formula {{chem2|CH3(CH2)6CO2(CH2)5CH3}}.

[[Image:Butyl acetate ester example.png|thumb|[[Butyl acetate]], an ester derived from a residue of [[butanol]] ({{chem2|CH3CH2CH2CH2OH}}) (the butanol residue is [[butyl group]] {{chem2|\sCH2CH2CH2CH3}}) (right side of the picture, blue) and [[acetic acid]] {{chem2|CH3CO2H}} (left side of the picture, orange). The [[acid]]ic [[hydrogen]] atom ({{chem2|\sH}}) from acetic acid [[molecule]] is replaced by the butyl group.]]

The chemical formulas of organic esters formed from carboxylic acids and alcohols usually take the form {{chem2|RCO2R'}} or RCOOR', where R and R' are the [[organyl]] parts of the carboxylic acid and the alcohol, respectively, and R can be a [[hydrogen]] in the case of esters of [[formic acid]]. For example, [[butyl acetate]] (systematically butyl ethanoate), derived from [[n-Butanol|butanol]] and [[acetic acid]] (systematically ethanoic acid) would be written {{chem2|CH3CO2(CH2)3CH3}}. Alternative presentations are common including BuOAc and {{chem2|CH3COO(CH2)3CH3}}.

Cyclic esters are called [[lactone]]s, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is [[gamma-valerolactone|γ-valerolactone]].