{{Chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 470473600 | ImageFileL1 = Thioformaldehyde-S,S-dioxide-2D.png | ImageClassL1 = skin-invert | ImageFileL1_Ref = {{chemboximage|correct|??}} | ImageSizeL1 = 121 | ImageNameL1 = Skeletal formula of sulfene with both explicit hydrogens added | ImageFileR1 = Thioformaldehyde-S,S-dioxide-3D-vdW.png | ImageClassR1 = bg-transparent | ImageFileR1_Ref = {{chemboximage|correct|??}} | ImageSizeR1 = 121 | ImageNameR1 = Spacefill model of sulfene | OtherNames = Thioformaldehyde-''S'',''S''-dioxide{{Citation needed|date = September 2011}}; Methanethione dioxide; Methylidene-λ<sup>6</sup>-sulfanedione |Section1={{Chembox Identifiers | CASNo_Ref = {{cascite|correct|pubchem}} | CASNo = 917-73-7 | PubChem = 12244237 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 10645700 | SMILES = C=S(=O)=O | StdInChI = 1S/CH2O2S/c1-4(2)3/h1H2 | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | InChI = 1/CH2O2S/c1-4(2)3/h1H2 | StdInChIKey = LZOZLBFZGFLFBV-UHFFFAOYSA-N | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | InChIKey = LZOZLBFZGFLFBV-UHFFFAOYAF }} |Section2={{Chembox Properties | Formula = {{Chem|CH|2|SO|2|}} | MolarMass = 78.090 g mol<sup>−1</sup> }} |Section3={{Chembox Structure | MolShape = trigonal planar at C and S }} }}
'''Sulfene''' is an extremely reactive chemical compound with the formula H<sub>2</sub>C=SO<sub>2</sub>. It is the simplest member of the '''sulfenes''', the group of compounds which are ''S'',''S''-dioxides of thioaldehydes and thioketones, and have the general formula R<sub>2</sub>C=SO<sub>2</sub>.<ref>{{GoldBookRef | file = S06095 | title = sulfenes}}</ref><ref>{{cite journal |last=Zwanenburg|first=B |title=S,S-Dioxides of Thioaldehydes and Thioketones (Sulfenes and Derivatives) |journal =Sci. Synth. |year=2004 |volume=27 |pages=123–134}}</ref><ref>{{cite journal |last=King|first=JF |title=Return of Sulfenes |journal =Acc. Chem. Res. |year=1975 |volume=8|issue=1|pages=10–17|doi=10.1021/ar50085a002}}</ref>
==Preparation== The first general method for preparation of sulfene as an intermediate, reported simultaneously in 1962 by Gilbert Stork<ref>{{cite journal|last=Stork|first=G|author2=Borowitz, IJ |title=Four-membered Sulfones from Enamines and Aliphatic Sulfonyl Halides|journal=J. Am. Chem. Soc.|year=1962|volume=84|issue=2|page=313|doi=10.1021/ja00861a042}}</ref> and by Günther Optiz,<ref>{{cite journal|last=Opitz|first=G|author2=Adolph, H |title=Cycloaddition of Sulfenes to Enamines|journal=Angew. Chem. Int. Ed. |year=1962|volume=1|issue=2|pages=113–114|doi=10.1002/anie.196201133}}</ref> involved the removal of hydrogen chloride from methanesulfonyl chloride using triethylamine in the presence of an enamine as trapping agent. The formation of a thietane 1,1-dioxide derivative was taken as evidence for the intermediacy of sulfene. Because of the highly electrophilic character of sulfene, the use of amines presents difficulties, since they can intercept the sulfene to form adducts. A simple alternative which avoids the use of amines involves desilylation of trimethylsilylmethanesulfonyl chloride with cesium fluoride in the presence of trapping agents.<ref>{{cite journal|last=Block|first=E|author2=Aslam, M |title=A New Sulfene Synthesis|journal=Tetrahedron Lett.|year=1982|volume=23|issue=41|pages=4203–4206|doi= 10.1016/S0040-4039(00)88704-3}}</ref>
: (CH<sub>3</sub>)<sub>3</sub>SiCH<sub>2</sub>SO<sub>2</sub>Cl + CsF → [CH<sub>2</sub>=SO<sub>2</sub>] + (CH<sub>3</sub>)<sub>3</sub>SiF + CsCl
Alternatively, sulfenes can be stabilized by installing amido substituents on the alkylidene substituent. The extreme case is thiourea dioxide, which features planar amido groups. :thumb|left|Structure of thiourea dioxide ((H<sub>2</sub>N)<sub>2</sub>CSO<sub>2</sub>). Selected distances and angles: r<sub>S=O</sub> = 1.49, r<sub>S=C</sub> = 1.85.1, r<sub>C-N</sub> = 1.31 Å, sum of angles around S = 312.4°.<ref>{{cite journal|journal=Acta Crystallogr.|year=1962|volume=15|pages=675–682|doi=10.1107/S0365110X62001851|title=The Crystal and Molecular Structure of Thiourea Dioxide|author=R. A. L. Sullivan |author2=A. Hargreaves |issue=7 |doi-access=free|bibcode=1962AcCry..15..675S }}</ref>
==Reactions== Sulfenes react with enamines, ynamines, and 1,3-cyclopentadienes to give thietanes, thietes and Diels-Alder adducts, respectively. In the presence of a chiral tertiary amine complex, several sulfenes could be trapped with trichloroacetaldehyde (chloral) in a catalytic asymmetric synthesis of β-sulfones (four-membered ring sulfonate esters).<ref>{{cite journal|last=Koch|first=FM|author2=Peters, R |title=Lewis Acid/Base Catalyzed [2+2]-Cycloaddition of Sulfenes and Aldehydes: A Versatile Entry to Chiral Sulfonyl and Sulfinyl Derivatives|journal=Chem. Eur. J.|year=2011|volume=17|issue=13 |pages=3679–3692|doi=10.1002/chem.201003542|pmid=21365709 }}</ref> Sulfene can also undergo insertion into metal–hydrogen bonds.<ref name="Lorenz">{{cite journal|author=Ingo-Peter Lorenz |title= Demonstration of "Sulfene" Insertion into the Metal–Hydrogen Bond |journal = Angew. Chem. Int. Ed. |volume=17|issue=4 |pages=285–286|date=April 1978 | doi = 10.1002/anie.197802851}}</ref>
==See also== * Sulfine - related functional group with the formula H<sub>2</sub>C=S=O
== References == {{reflist}}
Category:Organosulfur compounds