Editing Lactone (section)

==Reactions==
Lactones exhibit the reactions characteristic of esters.

===Hydrolysis and aminolysis===
Heating a lactone with a base ([[sodium hydroxide]]) will [[hydrolyse]] the lactone to its parent compound, the straight chained bifunctional compound. Like straight-chained esters, the hydrolysis-condensation reaction of lactones is a [[reversible reaction]], with an [[chemical equilibrium|equilibrium]]. However, the [[equilibrium constant]] of the hydrolysis reaction of the lactone is lower than that of the straight-chained ester i.e. the products (hydroxyacids) are less favored in the case of the lactones. This is because although the [[enthalpy|enthalpies]] of the hydrolysis of esters and lactones are about the same, the [[entropy]] of the hydrolysis of lactones is less than the entropy of straight-chained esters. Straight-chained esters give two products upon hydrolysis, making the entropy change more favorable than in the case of lactones which gives only a single product.

Lactones also react with amines to give the ring-opened alcohol and amide.

===Reduction===
Lactones can be reduced to diols using [[lithium aluminium hydride]]. For instance, gamma-lactones is reduced to butane-1,4-diol, (CH<sub>2</sub>(OH)-(CH<sub>2</sub>)<sub>2</sub>-CH<sub>2</sub>(OH).

=== Polymerization ===
Some lactones convert to polyesters:<ref>{{citation | author=Wilhelm Riemenschneider | author2=Hermann M. Bolt | contribution=Esters, Organic | title=[[Ullmann's Encyclopedia of Industrial Chemistry]] | edition=7th | publisher=Wiley | year=2007}}</ref><ref>{{Cite journal|last1=Chandru|first1=Kuhan|last2=Jia|first2=Tony Z.|last3=Mamajanov|first3=Irena|last4=Bapat|first4=Niraja|last5=Cleaves|first5=H. James|date=2020-10-16|title=Prebiotic oligomerization and self-assembly of structurally diverse xenobiological monomers|url= |journal=Scientific Reports|language=en|volume=10|issue=1|pages=17560|doi=10.1038/s41598-020-74223-5|issn=2045-2322|pmc=7567815|pmid=33067516|bibcode=2020NatSR..1017560C}}</ref> For example the double lactone called [[lactide]] polymerizes to [[polylactic acid]] (polylactide). The resulting polylactic acid has been heavily investigated for commercial applications.<ref>{{cite book | isbn = 978-0-470-29366-9 | title = Poly(lactic acid): Synthesis, Structures, Properties, Processing, and Applications | author1 = R. Auras | author2 = L.-T. Lim | author3= S. E. M. Selke |author4= H. Tsuji | publisher = Wiley | year = 2010 }}</ref><ref>{{cite journal|title=Controlled Ring-Opening Polymerization of Lactide and Glycolide|author1=Odile Dechy-Cabaret |author2=Blanca Martin-Vaca |author3=Didier Bourissou | journal=Chem. Rev.|year=2004|volume=104|issue=12|pages=6147–76|doi=10.1021/cr040002s|pmid=15584698}}</ref>

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