Term: esters
https://doi.org/10.1351/goldbook.E02219

Definition:
Compounds formally derived from an oxoacid RkE(=O)l(OH)m, (l ≠ 0) and an alcohol, phenol, heteroarenol, or enol by linking with formal loss of water from an acidic hydroxy group of the former and a hydroxy group of the latter. By extension acyl derivatives of alcohols, etc. Acyl derivatives of chalcogen analogues of alcohols (thiols, selenols, tellurols) etc. are included. E.g. R'C(=O)(OR), R'C(=S)(OR), R'C(=O)(SR), R'S(=O)2(OR), (HO)2P(=O)(OR), (R'S)2C(=O), ROCN (but not R–NCO) (R ≠ H).

Note: O-Alkyl derivatives of other acidic compounds [see @A00266@] may be named as esters but do not belong to the class esters proper. E.g. (Ph)2POCH3 methyl diphenylphosphinite.

Related Terms:
1) acylals (http://doi.org/10.1351/goldbook.A00119).
2) ortho esters (http://doi.org/10.1351/goldbook.O04334).
3) depsides (http://doi.org/10.1351/goldbook.D01603).
4) depsipeptides (http://doi.org/10.1351/goldbook.D01604).
5) glycerides (http://doi.org/10.1351/goldbook.G02647).
6) lactides (http://doi.org/10.1351/goldbook.L03436).
7) lactones (http://doi.org/10.1351/goldbook.L03439).
8) macrolides (http://doi.org/10.1351/goldbook.M03663).
9) amides (1) (http://doi.org/10.1351/goldbook.A00266).
10) oxoacid (http://doi.org/10.1351/goldbook.O04374).
11) acyl (http://doi.org/10.1351/goldbook.A00123).
12) alcohols (http://doi.org/10.1351/goldbook.A00204).
13) thiols (http://doi.org/10.1351/goldbook.T06359).
14) selenols (http://doi.org/10.1351/goldbook.S05574).

Source: PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1334 (https://doi.org/10.1351/pac199567081307)

Citation: 'esters' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.E02219

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