A large number of methods are known in the literature for the oxidation of sulfides (thioethers) to sulfoxides by electrophilic reagents. These include the use of peracids [10], NaIO 4 , hypochlorites, MnO 2 , CrO 3 , SeO 2 , and iodosobenzene. The use of these reagents has been reviewed up to 2005 [3, 4]. Hydrogen peroxide can also be used as a direct oxidant, although this reaction is slow in the absence of catalyst. Its use in catalytic reactions is discussed below in Section 8.2.2. 7 5 9 9 5 Ph S 8 15 94 280j 8 Selective Oxidation of Amines and Sulfides