4-Toluenesulfonyl chloride

{{chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 477223509 | ImageFile1=P-Toluenesulfonyl chloride structure.svg | ImageClass1 = skin-invert | ImageSize1=250px | ImageFile2=Tosyl-chloride-3D-vdW.png | ImageSize2=150px | ImageClass2 = bg-transparent | PIN= 4-Methylbenzene-1-sulfonyl chloride | OtherNames= Tosyl chloride, ''p''-toluenesulfonyl chloride, ''p''-TsCl, TsCl |Section1={{Chembox Identifiers | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 7119 | InChI = 1/C7H7ClO2S/c1-6-2-4-7(5-3-6)11(8,9)10/h2-5H,1H3 | InChIKey = YYROPELSRYBVMQ-UHFFFAOYAN | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChI = 1S/C7H7ClO2S/c1-6-2-4-7(5-3-6)11(8,9)10/h2-5H,1H3 | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = YYROPELSRYBVMQ-UHFFFAOYSA-N | CASNo_Ref = {{cascite|correct|CAS}} | CASNo= 98-59-9 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = 027KYN78B4 | PubChem=7397 | SMILES = O=S(Cl)(=O)c1ccc(cc1)C }} |Section2={{Chembox Properties | Formula=C₇H₇ClO₂S | MolarMass= 190.65 g/mol | Appearance=White solid | Density= | MeltingPtC = 65 to 69 | MeltingPt_notes = | BoilingPtC = 134 | BoilingPt_notes = at 10 mmHg | Solubility= Reacts with water }} |Section3={{Chembox Hazards | Hazards_ref = <ref>{{Cite web | url=http://chemicalland21.com/specialtychem/finechem/p-TOLUENESULFONYL%20CHLORIDE.htm | title=P-TOLUENESULFONYL CHLORIDE (TOSYL CHLORIDE)}}</ref> | MainHazards= Releases HCl on contact with water | FlashPtC =128 | AutoignitionPtC = | NFPA-H = 3 | NFPA-F = 1 | NFPA-R = 0 }} }}

'''4-Toluenesulfonyl chloride''' ('''''p''-toluenesulfonyl chloride''', '''toluene-''p''-sulfonyl chloride''') is an organic compound with the formula CH₃C₆H₄SO₂Cl. This white, malodorous solid is a reagent widely used in organic synthesis.<ref name=eEROS>{{ cite encyclopedia | author = Whitaker, D. T. | author2 = Whitaker, K. S. | author3 = Johnson, C. R. | author4 = Haas, J. | title = ''p''-Toluenesulfonyl Chloride | encyclopedia = Encyclopedia of Reagents for Organic Synthesis | year = 2006 | publisher = John Wiley | location = New York | doi = 10.1002/047084289X.rt136.pub2 | chapter-url = http://onlinelibrary.wiley.com/o/eros/articles/rt136/frame.html | access-date = 2013-05-28 | archive-url = https://web.archive.org/web/20160305090729/http://onlinelibrary.wiley.com/o/eros/articles/rt136/frame.html | archive-date = 2016-03-05 | url-status = dead | chapter = P-Toluenesulfonyl Chloride | isbn = 978-0471936237 }}</ref> Abbreviated '''TsCl''' or '''TosCl''', it is a derivative of toluene and contains a sulfonyl chloride (−SO₂Cl) functional group.

==Uses== {{main|Tosyl}} As typical for Sulfonyl halides, TsCl converts alcohols (abbreviated ROH) into the corresponding toluenesulfonate esters, or tosyl derivatives ("tosylates"): : CH₃C₆H₄SO₂Cl + ROH → CH₃C₆H₄SO₂OR + HCl Tosylates can be cleaved with lithium aluminium hydride: : 4 CH₃C₆H₄SO₂OR + LiAlH₄ → LiAl(O₃SC₆H₄CH₃)₄ + 4 RH Thus, tosylation followed by reduction allows for removal of a hydroxyl group.

Likewise, TsCl is used to prepare sulfonamides from amines:<ref>{{OrgSynth | author = Ichikawa, J. | author2 = Nadano, R. | author3 = Mori, T. | author4 = Wada, Y. | title = 5-''endo''-''trig'' Cyclization of 1,1-Difluoro-1-alkenes: Synthesis of 3-Butyl-2-Fluoro-1-Tosylindole | year = 2006 | volume = 83 | pages = 111 | collvol = 11 | collvolpages = 834 | prep = v83p0111 }}</ref> :CH₃C₆H₄SO₂Cl + R₂NH → CH₃C₆H₄SO₂NR₂ + HCl The resulting sulfonamides are non-basic and, when derived from primary amines, are even acidic.

TsCl reacts with hydrazine to give ''p''-toluenesulfonyl hydrazide.

The preparation of tosyl esters and amides are conducted in the presence of a base, which absorbs hydrogen chloride. The selection of the base is often crucial to the efficiency of tosylation. Typical bases include pyridine and triethylamine. Unusual bases are also used; for example, catalytic amounts of trimethylammonium chloride in the presence of triethylamine is highly effective by virtue of the trimethylamine.<ref name=eEROS/>

==Other reactions== Being a widely available reagent, TsCl has been heavily examined from the perspective of reactivity. It is used in dehydrations to make nitriles, isocyanides and diimides.<ref name=eEROS/> In an unusual reaction focusing on the sulfur center, zinc reduces TsCl to the sulfinate, CH₃C₆H₄SO₂Na.<ref>{{OrgSynth | author = Whitmore, F. C. | author2 = Hamilton, F. H. | title = Sodium Toluenesulfinate | year = 1922 | volume = 2 | pages = 89 | collvol = 1 | collvolpages = 492 | prep = CV1P0492 }}</ref>

==Manufacture== This reagent is inexpensively available for laboratory use. It is a by-product from the production of ortho-toluenesulfonyl chloride (a precursor for the synthesis of the common food additive and catalyst saccharin), via the chlorosulfonation of toluene:<ref>{{ Ullmann | author = Lindner, O. | author2 = Rodefeld, L. | title = Benzenesulfonic Acids and Their Derivatives | doi = 10.1002/14356007.a03_507 }}</ref> : CH₃C₆H₅ + SO₂Cl₂ → CH₃C₆H₄SO₂Cl + HCl == Hazards == Tosyl chloride is "a corrosive lachrymator."<ref name=eEROS/>

==References== {{reflist}}

{{DEFAULTSORT:Toluenesulfonyl chloride, 4-}} Category:Reagents for organic chemistry Category:Sulfonyl halides Category:p-Tosyl compounds Category:Foul-smelling chemicals Category:Chlorides