SO2C6H4CH3

SO2C6H4CH3, also known as p-toluenesulfonyl chloride or tosyl chloride, is an organic compound with the chemical formula CH3C6H4SO2Cl. It is a derivative of toluene and sulfuryl chloride. It typically appears as a white solid. This compound is a widely used reagent in organic synthesis, particularly for the conversion of alcohols into tosylates. Tosylates are good leaving groups, making them useful in substitution and elimination reactions. It is also employed in the protection of amines and alcohols. The reaction of tosyl chloride with alcohols in the presence of a base, such as pyridine or triethylamine, forms the corresponding tosylate ester. Similarly, reaction with amines yields sulfonamides. Tosyl chloride is a key intermediate in the production of various pharmaceuticals and other fine chemicals. It is important to handle tosyl chloride with care as it is a lachrymator and can be irritating to the skin and respiratory system. Proper ventilation and personal protective equipment are recommended when working with this chemical. Its preparation often involves the reaction of p-toluenesulfonic acid with phosphorus pentachloride or thionyl chloride.