View source for Sulfone

{{Short description|1=Organosulfur compound of the form >S(=O)2}}
[[File:Sulfone.svg|thumb|150px|right|The structure of a sulfone]]
[[File:Dimethylsulfone-3D-vdW.png|thumb|[[Methylsulfonylmethane|Dimethyl sulfone]], an example of a sulfone]]

In [[organic chemistry]], a '''sulfone''' is a [[organosulfur compound]] containing a [[sulfonyl]] ({{chem2|R\sS(\dO)2\sR’}}) [[functional group]] attached to two [[carbon]] atoms. The central [[Valence (chemistry)|hexavalent]] [[sulfur]] atom is [[double-bond]]ed to each of two [[oxygen]] atoms and has a single bond to each of two carbon atoms, usually in two separate hydrocarbon [[substituent]]s.<ref name="ISBN 9780534389512">{{cite book | last = Hornback | first = Joseph | title = Organic Chemistry | publisher = Thomson Brooks/Cole | location = Australia | year = 2006 | isbn = 978-0-534-38951-2}}</ref>

==Synthesis and reactions==
===By oxidation of thioethers and sulfoxides===
Sulfones are typically prepared by [[organic oxidation]] of [[thioether]]s, often referred to as [[sulfide]]s. [[Sulfoxide]]s are intermediates in this route.<ref>{{cite journal|title=Phenyl Vinyl Sulfone and Sulfoxide|author=Leo A. Paquette, Richard V. C. Carr|journal=Org. Synth.|year=1986|volume=64|page=157|doi=10.15227/orgsyn.064.0157}}</ref> For example, [[dimethyl sulfide]] oxidizes to [[dimethyl sulfoxide]] and then to [[Methylsulfonylmethane|dimethyl sulfone]].<ref name="ISBN 9780534389512"/>

===From SO<sub>2</sub>===
:[[Image:Sulfolane synthesis.png|upright=1.5|right|thumb|Synthesis of sulfolane by [[hydrogenation]] of [[sulfolene]].]]
[[Sulfur dioxide]] is a convenient and widely used source of the sulfonyl functional group. Specifically, Sulfur dioxide participates in cycloaddition reactions with dienes.<ref>{{cite journal|title=Isoprene Cyclic Sulfone|author=Robert L. Frank and Raymond P. Seven|journal=Org. Synth.|year=1949|volume=29|pages=59|doi=10.15227/orgsyn.029.0059}}</ref>
The industrially useful solvent [[sulfolane]] is prepared by addition of sulfur dioxide to [[butadiene|buta-1,3-diene]] followed by hydrogenation of the resulting sulfolene.<ref name=Ullmann>{{Ullmann | first = Hillis O. | last = Folkins | chapter = Benzene |  date = 2005 | DOI = 10.1002/14356007.a03_475}}</ref>

===From sulfonyl and sulfuryl halides===
Sulfones are prepared under conditions used for [[Friedel–Crafts reaction]]s using sources of {{chem|RSO|2|+}} derived from [[sulfonyl halides]] and [[methanesulfonic anhydride|sulfonic acid anhydrides]]. [[Lewis acid]] catalysts such as {{chem2|AlCl3}} and {{chem2|FeCl3}} are required.<ref>{{cite journal |author1=Truce, W. E. |author2=Vriesen |author3=C. W. | title = Friedel—Crafts Reactions of Methanesulfonyl Chloride with Benzene and Certain Substituted Benzenes| year = 1953 | journal = [[J. Am. Chem. Soc.]] | volume = 75 | pages = 5032–5036 | doi = 10.1021/ja01116a043 | issue = 20}}</ref><ref>{{Cite journal | last1 = Répichet | first1 = S. | last2 = Le Roux | first2 = C. | last3 = Hernandez | first3 = P. | last4 = Dubac | first4 = J. | last5 = Desmurs | first5 = J. R. | title = Bismuth(III) Trifluoromethanesulfonate: An Efficient Catalyst for the Sulfonylation of Arenes | doi = 10.1021/jo9902603 | journal = The Journal of Organic Chemistry | volume = 64 | issue = 17 | pages = 6479–6482 | year = 1999 }}</ref><ref>{{cite journal |author1=Truce, W. E. |author2=Milionis, J. P. | title = Friedel-Crafts Cyclization of ω-Phenylalkanesulfonyl Chlorides | year = 1952 | journal = [[J. Am. Chem. Soc.]] | volume = 74 | pages = 974–977 | doi = 10.1021/ja01124a031 | issue = 4}}</ref>

Sulfones have been prepared by [[nucleophilic displacement]] of [[halide]]s by [[sulfinate]]s:<ref>{{cite journal|title=4,4'-Diaminodiphenylsulfone|author=C. W. Ferry, J. S. Buck, R. Baltzly|journal=Org. Synth.|year=1942|volume=22|pages=31|doi=10.15227/orgsyn.022.0031}}</ref> <chem display=block>ArSO2Na  +  Ar'Cl  ->  Ar(Ar')SO2  +  NaCl</chem>  In general, relatively nonpolar ("[[HSAB|soft]]") alkylating agents react with sulfinic acids to give sulfones, whereas polarized ("hard") alkylating agents form esters.<ref>{{Ullmann|doi=10.1002/14356007.a25_461|title=Sulfinic Acids and Derivatives|first=R&uuml;diger|last=Schubart|p=682}}</ref>  [[Allyl]], [[propargyl]],<ref>S. Braverman and T. Pechenick, ''Tetrahedron Lett.'', 43, 499 (2002).  {{doi|10.1016/S0040-4039(01)02174-8}}</ref> and [[benzyl]]<ref>{{cite journal|doi=10.1039/JR9300001676|first1=Joseph|last1=Kenyon|first2=Henry|last2=Phillips|title=The optical instability of tercovalent carbonium kations|date=3 June 1930|journal=Journal of the Chemical Society}}</ref> sulfinates can thermally rearrange to the sulfone, but esters without an activated bond generally do not rearrange so.<ref>{{cite journal|doi=10.1021/ja01157a018|date=Jan 1950|title=Thermal rearrangement of allyl-type sulfoxides, sulfones and sulfinates|first1=Arthur&nbsp;C.|last1=Cope|first2=Dwight&nbsp;E.|last2=Morrison|first3=Lamar|last3=Field|volume=72|page=60|orig-date=21 June 1949|journal= Journal of the American Chemical Society}}</ref>

===Reactions===
Sulfone is a relatively inert functional group, typically less oxidizing and 4 [[bel (unit)|bel]] more acidic than sulfoxides.  In the [[Ramberg–Bäcklund reaction]] and the [[Julia olefination]], sulfones are converted to [[alkene]]s by the elimination of [[sulfur dioxide]].<ref>{{cite book | first1 = Francis A. | last1 = Carey | first2 = Richard J. | last2 = Sundberg | title = Advanced Organic Chemistry | publisher = Springer | location = Berlin | year = 2007 | isbn = 978-0-387-68354-6}}</ref>  However, sulfones are unstable to bases, [[elimination reaction|eliminating]] to give an alkene.<ref>Smith (2020), ''March's Organic Chemistry'', rxn.&nbsp;17-10.</ref>  

Sulfones can also undergo [[desulfonylation reactions|desulfonylation]].

[[Vinyl sulfone]]s are electrophilic and behave as [[Michael acceptor]]s.

==Applications==
[[Sulfolane]] is used to extract valuable aromatic compounds from petroleum.<ref name=Ullmann/>

===Polymers===
Some polymers containing sulfone groups are useful engineering plastics. They exhibit high strength and resistance to oxidation, corrosion, high temperatures, and creep under stress. For example, some are valuable as replacements for copper in domestic hot water plumbing.<ref>{{cite book | last = Fink | first = Johannes | title = High Performance Polymers | publisher = William Andrew | location = Norwich | year = 2008 | isbn = 978-0-8155-1580-7}}</ref>  Precursors to such polymers are the sulfones [[bisphenol S]] and [[4,4'-Dichlorodiphenyl sulfone|4,4′-dichlorodiphenyl sulfone]].

===Pharmacology===
[[file:Dapsone.svg|thumb|222px|[[Dapsone]], an [[antibiotic]] used for the treatment of [[leprosy]].<ref>{{cite book |author1=Thomas L. Lemke |title=Foye's Principles of Medicinal Chemistry |date=2008 |publisher=Lippincott Williams & Wilkins |isbn=9780781768795 |page=1142 |url=https://books.google.com/books?id=R0W1ErpsQpkC&pg=PA1142 |url-status=live |archive-url=https://web.archive.org/web/20160304193954/https://books.google.ca/books?id=R0W1ErpsQpkC&pg=PA1142 |archive-date=2016-03-04}}</ref>]]
Examples of sulfones in pharmacology include [[dapsone]], a drug formerly used as an [[antibiotic]] to treat [[leprosy]], [[dermatitis herpetiformis]], [[tuberculosis]], or [[pneumocystis pneumonia]] (PCP). Several of its derivatives, such as [[promin]], have similarly been studied or actually been applied in medicine, but in general sulfones are of far less prominence in pharmacology than for example the [[Sulfonamide (medicine)|sulfonamides]].<ref>{{cite book | first1 = Charles R. | last1 = Craig | first2 = Robert E. | last2 = Stitzel | title = Modern Pharmacology with Clinical Applications | publisher = Lippincott Williams & Wilkins | location = Hagerstwon | year = 2004 | isbn = 978-0-7817-3762-3}}</ref><ref>{{cite book | first1 = Victor Alexander | last1 = Drill | first2 = Joseph R. | last2 = Di Palma | title = Drill's Pharmacology in Medicine | publisher = McGraw-Hill | location = New York | year = 1971 | isbn = 978-0-07-017006-3}}</ref>

==See also==
{{Commons category|Sulfones}}
*[[Organosulfur chemistry]]
*[[Sulfonanilide]]
*[[Sulfoxide]]
*[[Sulfonic acid]] (–OH substituent)

==References==
{{Reflist|30em}}

{{Functional Groups}}

[[Category:Sulfones| ]]
[[Category:Functional groups]]