{"product_id":"kosers-reagent-cas-27126-76-7","title":"Koser's reagent (HTIB) | CAS 27126-76-7 | ≥96%","description":"\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eTechnical Specifications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; font-size: 0.95em; border: 1px solid #e4e8f0; border-top: none; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eCAS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e27126-76-7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eEC \/ EINECS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e629-501-8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMDL Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eMFCD00011547\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSMILES\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eCC1=CC=C(C=C1)S(=O)(=O)OI(C2=CC=CC=C2)O\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChI\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eInChI=1S\/C13H13IO4S\/c1-11-7-9-13(10-8-11)19(16,17)18-14(15)12-5-3-2-4-6-12\/h2-10,15H,1H3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChIKey\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eLRIUKPUCKCECPT-UHFFFAOYSA-N\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePubChem CID\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e325434\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Formula\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eC₁₃H₁₃IO₄S\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Weight\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e392.21 g\/mol\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMelting Point\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e136–142 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSolubility\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eSoluble in methanol, DMSO and hot acetonitrile. Moderately soluble in water. Insoluble in diethyl ether; largely insoluble in dichloromethane, chloroform and cold acetonitrile.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePurity\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e≥96%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePhysical Form\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eWhite to light yellow powder to crystal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eHS Code\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e2904.99\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eShelf Life\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eRetest period: 36 months from date of manufacture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eStorage Conditions\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eStore at room temperature in a tightly sealed container, protected from light\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eProduct Description \u0026amp; Scientific Applications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"padding: 16px 20px; border: 1px solid #e4e8f0; border-top: none; font-family: Georgia, 'Times New Roman', serif; font-size: 0.95em; line-height: 1.65; color: #333;\"\u003e\n\u003cp\u003e\u003cstrong\u003eKoser's reagent\u003c\/strong\u003e, [hydroxy(tosyloxy)iodo]benzene or HTIB (C13H13IO4S), is a hypervalent iodine(III) oxidant carrying both a hydroxy and a tosyloxy group on the same iodine. That mixed pair is the point: the two ligands differ so widely in effective electronegativity that the reagent ionises in solution at room temperature, and tosylate is the better nucleofuge, making it more reactive than the diacetoxy analogue.\u003c\/p\u003e\n\u003cp\u003eIt is used as a crystalline solid, added directly to the substrate in 95% methanol at room temperature. In fluoroalcohol media — trifluoroethanol or HFIP — it switches mode, generating aromatic cation radicals by single-electron transfer. Its relatively benign character compared with thallium(III) nitrate and silver nitrate is a practical reason it displaced those oxidants.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eApplications and Reactions\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eArylalkenes to α-aryl ketones:\u003c\/strong\u003e in 95% methanol, regiospecifically. The transformation the reagent is best known for.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eα-Tosyloxylation of ketones:\u003c\/strong\u003e installs a tosyloxy leaving group at the α-carbon, the first step of a two-step route to α-haloketones — and a route to the same products without handling toxic, lachrymatory α-haloketones at all.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeterocycles from α-tosyloxy ketones:\u003c\/strong\u003e with primary selenoamides in refluxing acetonitrile\/methanol they give 1,3-selenazoles; with 3-alkyl\/aryl-4-amino-5-mercapto-1,2,4-triazoles in refluxing ethanol, triazolothiadiazines in 67–93% yield.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOxidative aromatisation:\u003c\/strong\u003e converts Hantzsch 1,4-dihydropyridines to the corresponding pyridines in dichloromethane at room temperature, in good to excellent yields.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRing expansion:\u003c\/strong\u003e 1-vinylcycloalkanol derivatives to ring-expanded oxygen heterocycles in one oxidative step, 72–88% yield.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNitrogen deletion:\u003c\/strong\u003e with ammonium carbamate, a pyrrolidine becomes a densely substituted cyclobutane in 58% yield as a single diastereomer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHofmann–Löffler–Freytag:\u003c\/strong\u003e as oxidant with 4 equivalents of sodium carbonate as bulking additive, 84% yield under mechanochemical conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIodonium salt synthesis:\u003c\/strong\u003e dehydrative condensation with uracil in fluoroalcohol medium gives uracil-aryliodonium(III) tosylates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCatalytic use:\u003c\/strong\u003e with \u003cem\u003em\u003c\/em\u003e-CPBA as terminal oxidant it is regenerated in situ, converting symmetrical dialkyl bromoalkenes to α-bromoketones in 49–54% isolated yield.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLimitations:\u003c\/strong\u003e in sulfonyloxylation, HTIB added as the solid gave 26% against 65% for iodine(III) generated in situ — the difference is the strongly acidic medium, which activates the iodine(III) centre, so added TsOH is worth trying. In ring contraction of 1,2-dihydronaphthalenes it forms more addition by-products than thallium(III) nitrate, and some alkenes in methanol give a complex mixture.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStorage:\u003c\/strong\u003e room temperature in a tightly sealed container, protected from light.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eShipping Destinations\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e4e8f0; border-top: none; padding: 12px 16px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.95em;\"\u003e\u003cul style=\"margin: 0; padding: 0; list-style: none;\"\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEU \u0026amp; UK: Priority delivery, 2–5 business days.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eUnited States (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEFTA Countries (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eWorldwide: 7–14 business days, selected locations.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"NorrChemica™","offers":[{"title":"5.0 g","offer_id":54356139409745,"sku":"NOR-27126767-5g","price":39.2,"currency_code":"EUR","in_stock":true},{"title":"10 g","offer_id":54525577363793,"sku":"NOR-27126767-10g","price":57.2,"currency_code":"EUR","in_stock":true},{"title":"25 g","offer_id":54356139442513,"sku":"NOR-27126767-25g","price":94.2,"currency_code":"EUR","in_stock":true},{"title":"50 g","offer_id":54525577396561,"sku":"NOR-27126767-50g","price":169.2,"currency_code":"EUR","in_stock":true},{"title":"100 g","offer_id":54525577429329,"sku":"NOR-27126767-100g","price":279.2,"currency_code":"EUR","in_stock":true},{"title":"250 g","offer_id":54525577462097,"sku":"NOR-27126767-250g","price":449.2,"currency_code":"EUR","in_stock":true},{"title":"500 g","offer_id":54525577494865,"sku":"NOR-27126767-500g","price":879.2,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/6357\/1793\/files\/NorrChemica_HTIB.png?v=1786281745","url":"https:\/\/www.norrchemica.com\/products\/kosers-reagent-cas-27126-76-7","provider":"NorrChemica","version":"1.0","type":"link"}