organic chemistry Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic matter, organic materials, i.e., matter in its various forms that contain ...

, a sulfone is a

organosulfur compound Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur der ...

containing a

sulfonyl In organosulfur chemistry, a sulfonyl group is either a functional group found primarily in sulfones, or a substituent obtained from a sulfonic acid by the removal of the hydroxyl group, similarly to acyl groups. Group Sulfonyl groups can be w ...

()

functional group In organic chemistry, a functional group is any substituent or moiety (chemistry), moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions r ...

attached to two

carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...

atoms. The central hexavalent

sulfur Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ...

atom is double-bonded to each of two

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

atoms and has a single bond to each of two carbon atoms, usually in two separate hydrocarbon

substituent In organic chemistry, a substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. The suffix ''-yl'' is used when naming organic compounds that contain a single bond r ...

Synthesis and reactions

By oxidation of thioethers and sulfoxides

Sulfones are typically prepared by

organic oxidation Organic reductions or organic oxidations or organic redox reactions are redox reactions that take place with organic compounds. In organic chemistry oxidations and reductions are different from ordinary redox reactions, because many reactions carr ...

thioether In organic chemistry, a sulfide (British English sulphide) or thioether is an organosulfur functional group with the connectivity as shown on right. Like many other sulfur-containing compounds, Volatile organic compound, volatile sulfides have ...

s, often referred to as

sulfide Sulfide (also sulphide in British English) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to large families o ...

Sulfoxide In organic chemistry, a sulfoxide, also called a sulphoxide, is an organosulfur compound containing a sulfinyl () functional group attached to two carbon atoms. It is a polar functional group. Sulfoxides are oxidized derivatives of sulfides. E ...

s are intermediates in this route. For example,

dimethyl sulfide Dimethyl sulfide (DMS) or methylthiomethane is an organosulfur compound with the formula . It is the simplest thioether and has a characteristic disagreeable odor. It is a flammable liquid that boils at . It is a component of the smell produc ...

oxidizes to

dimethyl sulfoxide Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula . This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is ...

and then to dimethyl sulfone.

From SO₂

Sulfur dioxide Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...

is a convenient and widely used source of the sulfonyl functional group. Specifically, Sulfur dioxide participates in cycloaddition reactions with dienes. The industrially useful solvent

sulfolane Sulfolane (also tetramethylene sulfone, IUPAC nomenclature, systematic name: 1λ6-thiolane-1,1-dione) is an organosulfur compound, formally a cyclic sulfone, with the formula . It is a colorless liquid commonly used in the chemical industry as a s ...

is prepared by addition of sulfur dioxide to buta-1,3-diene followed by hydrogenation of the resulting sulfolene.

From sulfonyl and sulfuryl halides

Sulfones are prepared under conditions used for

Friedel–Crafts reaction The Friedel–Crafts reactions are a set of organic reaction, reactions developed by Charles Friedel and James Crafts in 1877 to attach substituents to an Aromatic hydrocarbon, aromatic ring. Friedel–Crafts reactions are of two main types: alky ...

s using sources of derived from

sulfonyl halides In chemistry, a sulfonyl halide consists of a sulfonyl () functional group, group Single bond, singly bonded to a halogen atom. They have the general Chemical formula, formula , where X is a halogen. The Chemical stability, stability of sulfonyl h ...

and sulfonic acid anhydrides.

Lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any ...

catalysts such as and are required. Sulfones have been prepared by

nucleophilic displacement In chemistry, a nucleophilic substitution (SN) is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile). ...

halide In chemistry, a halide (rarely halogenide) is a binary chemical compound, of which one part is a halogen atom and the other part is an element or radical that is less electronegative (or more electropositive) than the halogen, to make a fl ...

s by

sulfinate Sulfinic acids are oxoacids of sulfur with the structure RSO(OH). In these organosulfur compounds, sulfur is Molecular geometry, pyramidal. Structure and properties Sulfinic acids RSO2H are typically more acidic than the corresponding carboxyl ...

s: ArSO2Na + Ar'Cl -> Ar(Ar')SO2 + NaCl In general, relatively nonpolar (" soft") alkylating agents react with sulfinic acids to give sulfones, whereas polarized ("hard") alkylating agents form esters.

Allyl In organic chemistry, an allyl group is a substituent with the structural formula . It consists of a methylene bridge () attached to a vinyl group (). The name is derived from the scientific name for garlic, . In 1844, Theodor Wertheim isolated a ...

propargyl In organic chemistry, the propargyl group is a functional group of 2- propynyl with the structure . It is an alkyl group derived from propyne (). The term propargylic refers to a saturated position ( ''sp''3-hybridized) on a molecular framework ...

, and

benzyl In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure . Benzyl features a benzene ring () attached to a methylene group (). Nomenclature In IUPAC nomenclature, the prefix benzyl refers to a substituent ...

sulfinates can thermally rearrange to the sulfone, but esters without an activated bond generally do not rearrange so.

Reactions

Sulfone is a relatively inert functional group, typically less oxidizing and 4 bel more acidic than sulfoxides. In the Ramberg–Bäcklund reaction and the Julia olefination, sulfones are converted to

alkene In organic chemistry, an alkene, or olefin, is a hydrocarbon containing a carbon–carbon double bond. The double bond may be internal or at the terminal position. Terminal alkenes are also known as Alpha-olefin, α-olefins. The Internationa ...

s by the elimination of

sulfur dioxide Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...

. However, sulfones are unstable to bases, eliminating to give an alkene. Sulfones can also undergo desulfonylation. Vinyl sulfones are electrophilic and behave as Michael acceptors.

Applications

Sulfolane Sulfolane (also tetramethylene sulfone, IUPAC nomenclature, systematic name: 1λ6-thiolane-1,1-dione) is an organosulfur compound, formally a cyclic sulfone, with the formula . It is a colorless liquid commonly used in the chemical industry as a s ...

is used to extract valuable aromatic compounds from petroleum.

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. Precursors to such polymers are the sulfones bisphenol S and 4,4′-dichlorodiphenyl sulfone.

Pharmacology

222px, Dapsone, an antibiotic used for the treatment of leprosy">antibiotic.html" ;"title="Dapsone, an antibiotic">Dapsone, an antibiotic used for the treatment of leprosy. 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

sulfonamides In organic chemistry, the sulfonamide functional group (also spelled sulphonamide) is an organosulfur group with the Chemical structure, structure . It consists of a sulfonyl group () connected to an amine group (). Relatively speaking this gro ...

References

{{Functional Groups Functional groups