{{chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 448762476 | ImageFile=Thiiren.png | ImageSize=80px | PIN=Thiirene | SystematicName = Thiacyclopropene | OtherNames=Epithioethene<br />Ethyne sulfide<br />Acetylene sulfide |Section1={{Chembox Identifiers | CASNo=157-20-0 | PubChem=5461041 | SMILES=C1=CS1 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 4574411 | InChI = 1/C2H2S/c1-2-3-1/h1-2H | InChIKey = JTQAPFZZCXWQNQ-UHFFFAOYAN | StdInChI_Ref = {{stdinchicite|changed|chemspider}} | StdInChI = 1S/C2H2S/c1-2-3-1/h1-2H | StdInChIKey_Ref = {{stdinchicite|changed|chemspider}} | StdInChIKey = JTQAPFZZCXWQNQ-UHFFFAOYSA-N | MeSHName = | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = 30976 | Beilstein = 1304471 | Gmelin = 239545 }} |Section2={{Chembox Properties | Formula=C<sub>2</sub>H<sub>2</sub>S | MolarMass=58.10228 | Appearance= | Density= | MeltingPt= | BoilingPt= | Solubility= }} }}
'''Thiirene''' is an organosulfur compound with the formula C<sub>2</sub>H<sub>2</sub>S. It can be viewed as a derivative of cyclopropene, but with the methylene group replaced by sulfur. It is antiaromatic and very labile.<ref>{{cite book |doi=10.1016/B978-008096518-5.00005-8|chapter=Thiiranes and Thiirenes: Monocyclic|title=Comprehensive Heterocyclic Chemistry II|year=1996|last1=Ando|first1=Wataru|last2=Choi|first2=Nami|last3=Tokitoh|first3=Norihiro|pages=173–240|isbn=9780080965185}}</ref>
==Thiirenes and derivatives== No thiirene has been isolated at room temperature, but they have been observed spectroscopically at low temperatures.<ref>{{cite journal |doi=10.1021/jo00406a045|title=Low-Temperature Matrix Isolation of Thiirenes|year=1978|last1=Torres|first1=M.|last2=Clement|first2=A.|last3=Bertie|first3=J. E.|last4=Gunning|first4=H. E.|last5=Strausz|first5=O. P.|journal=The Journal of Organic Chemistry|volume=43|issue=12|pages=2490–2493}}</ref>
Thiirene-''S''-oxides and ''S''-alkylthiirenium salts have been characterized by X-ray crystallography.<ref>{{cite journal |doi=10.1021/jo991731o|title=X-ray Structures and Anionotropic Rearrangements of Di-tert-butyl-Substituted Thiiranium and Thiirenium Ions. A Structure−Reactivity Relationship|year=2000|last1=Destro|first1=Riccardo|last2=Lucchini|first2=Vittorio|last3=Modena|first3=Giorgio|last4=Pasquato|first4=Lucia|journal=The Journal of Organic Chemistry|volume=65|issue=11|pages=3367–3370|pmid=10843618}}</ref>
==References== <references /> {{organic-compound-stub}} Category:Sulfur heterocycles Category:Three-membered rings