10 - Oxidation of Organic Compounds

Abstract

The oxidation of organic compounds by water-soluble inorganic oxidants is often made difficult not only by the insolubility of the organic substrate in water, but also by the susceptibility of many of the miscible non-aqueous solvents to oxidation. Solubilization of the ionic oxidant into solvents such as benzene, chloroform, dichloromethane or 1, 2-dichlorobenzene, by phase-transfer catalysts obviates these problems, although it has been suggested that dichloromethane should not be used, as it is also susceptible to oxidation. The use of potassium permanganate as an oxidizing agent in organic synthesis has been reviewed up to 1986 with a summary of its application under phase transfer conditions. The permanganate anion forms strong ion-pairs with many quaternary ammonium cations and, for example, relatively low concentrations of tetra-n-butylammonium salts are required for the efficient transfer of the permanganate anion into an organic solvent.