The study of organic reactions in water solution is a subject current interest among organic chemist in order to develop methods more friendly to the environment. The use of Lewis catalyst in water is a challenging subject.1 We have demonstrated that FeBr3 form a very stable complex with beta-cyclodextrin and that this complex is very effective catalyst in sulfoxidation reactions.2 We present here some new results regarding the oxidation reaction of several organic sulfides catalyzed by FeBr3 in basic water solution. These reactions can be done in this reaction media because ciclodextrins strongly stabilize Fe+3 cation in water. The reactions were carried out in water with small content of acetonitrile using H2O2 or Fe(NO3)3 as oxidants and the complex beta-cyclodextrin-FeBr3 as catalyst. Under this conditions p-nitrophenyl methyl sulphide is oxidized to sulfoxide and also to the sufone. In the presence of cyclodextrin the selectivity for the sulfoxide formation increases considerably and the overall reaction is slower. We will discuss also results regarding the effect of the cyclodextrin-FeBr3 complex on the selectivity for the oxidation of [4-(methylthio)phenyl]methanol and 4-(methylthio)benzaldehyde in acetonitrile as solvent and the efficiency of the cyclodextrin complex as catalyst will be compared with that of FeBr3, [(FeBr3)2(DMSO)3] and Fe(acac). References 1.-Lindstrom, U. M.; Chem. Rev. 2002; 102, 2751-2772. 2- Rossi, L.I.; de Rossi, R.H. App. Catal. A : General 2004, 267, 267-272.
