The general procedure for the synthesis of isopropyl p-toluenesulfonate from sodium p-toluenesulfinate and isopropanol is as follows: to a solvent mixture containing dichloromethane (0.5 mL) and ethanol (0.5 mL) at room temperature, iodobenzene diacetate (DIB, 0.24 mmol, 1.2 eq.), sodium p-toluenesulfinate (0.2 mmol, 1 eq.), and acetic acid ( 0.01 g, 0.05 mL) or tetrabutylammonium chloride (TBAC, 55.5 mg, 0.2 mmol, 2 equiv) to dissolve the sulfonate. The reaction mixture was reacted under vigorous stirring for 15 minutes and subsequently monitored by thin layer chromatography (TLC) using a solvent mixture of acetic acid/ethyl acetate/hexane. Upon completion of the reaction, the mixture was filtered through silica gel and washed with ethyl acetate. Ultimately, the residue was purified by silica gel column chromatography using a mixed solvent of ethyl acetate/hexane to give the target product isopropyl p-toluenesulfonate (products 4, 6 and 8).
