| Abstract
| - The synthesis of novel hydroperoxy sultams 1b−d and their potential as renewable chemoselectiveelectrophilic oxidants for a wide range of nitrogen, sulfur, and phosphorus heteroatoms innonaqueous media is described. Reactions of 1b,c with secondary amines 10f,g yielded thehydroxysultams 2b,c and nitrone 11f or radical 11g depending on the substrate and stoichiometry,while tertiary amines 10a−d gave amine oxides 11a−d. Compounds 1c,d oxidized various thioethers12a−g to sulfoxides 13a−g smoothly that were isolated by chromatography in nearly quantitativeyields. 1c was regenerated from 2c by treatment of the latter with acidified H2O2. Kinetic studiesof the reaction of 1c with 1,4-thioxane 12f suggest that the reaction follows the second-order kinetics,first order in substrate and first order in oxidant with the second-order rate constant several ordersof magnitude larger than that of the corresponding reaction with hydrogen peroxide and tert-butylhydroperoxide without the need for any acid or heavy metal catalysts. The phosphines 14a,b werealso oxidized by 1c to the respective phosphine oxides 15a,b readily in quantitative yields. Thereactions may be conducted at ambient temperature or lower and appear to proceed via a nonradicalmechanism. Reactions are sensitive to steric as well as electronic factors.
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