Dimethyl(methylthio)sulfonium trifluoromethanesulfonate

Abstract

[85055-60-3] C3H9S2+ CF3O3S− (MW 258.30) InChI = 1S/C3H9S2.CHF3O3S/c1-4-5(2)3;2-1(3,4)8(5,6)7/h1-3H3;(H,5,6,7)/q+1;/p-1 InChIKey = TXVLFCLSVCYBIV-UHFFFAOYSA-M (methylsulfenylating agent; activates thioglycosides and other types of glycosyl donors for glycoside synthesis1-3) Alternate Name: dimethyl(methylthio)sulfonium triflate, dimethylthiomethyl sulfonium trifluoromethanesulfonate, DMTST. Physical Data: mp 28–36 °C;4 53–55 °C.5 Variation in reported melting points is probably due to the hygroscopic nature of the reagent. Solubility: soluble in CH2Cl2, MeCN, MeNO2; sparingly soluble in diethyl ether, benzene, toluene; insoluble in petroleum ether. Form Supplied in: white crystals; not commercially available. Analysis of Reagent Purity: 1H NMR. Purification: recrystallization from dichloromethane–diethyl ether. Preparative Methods: readily prepared by alkylation of methyl disulfide with methyl trifluoromethanesulfonate in dichloromethane1, 4, 5 or neat6 (eq 1). The reagent crystallizes from dichloromethane by the addition of diethyl ether. Alternatively, the dichloromethane solution can be used directly for most applications. (1) Handling, Storage, and Precautions: the reagent is hygroscopic, it liquifies in air. Store in a closed vessel or over a strong drying agent, preferably, in the refrigerator. A 1 M solution in dichloromethane, which partially crystallizes on storage in the refrigerator, can be stored for prolonged periods of time.1 In cases of doubts the use of freshly prepared DMTST is recommended.