Copper(II) Toluenesulfonate

Abstract

[7144-37-8] C14H14S2O6Cu (MW 405.98) InChI = 1S/2C7H8O3S.Cu/c2*1-6-2-4-7(5-3-6)11(8,9)10;/h2*2-5H,1H3,(H,8,9,10);/q;;+2/p-2 InChIKey = MRYMYQPDGZIGDM-UHFFFAOYSA-L (reagent for regiospecific α-sulfonyloxylation of unsymmetrical ketones and a source of weakly coordinating anion in palladium-catalyzed reactions) Physical Data: reagent decomposes at ≥ 290 °C. Solubility: soluble in acetonitrile and many polar solvents. Analysis of Reagent Purity: metal content determined by EDTA complexometry using a murexide indicator; anion determination using acid cation exchange resin followed by titration of eluted acid with NaOH.1 Preparative Methods: readily isolated as a pale-blue hexahydrate complex from aqueous reaction of either p-toluenesulfonic acid and copper(II) carbonate1 or stoichiometric amounts of silver(I) p-toluenesulfonate and copper(II) chloride dihydrate.2 The reagent is prepared in situ via reaction of copper oxide and p-toluenesulfonic acid in refluxing CH3CN.3 Purification: dried at 70 °C under vacuum to give the pale-green anhydrous reagent. Handling, Storage, and Precautions: can be stored indefinitely at room temperature under an inert atmosphere.