The oxidation of organic sulphides (n-Bu2S, PhSCH3, Tolyl-SCH3, p-Cl-C6H4SCH3, and Ph2S by (HMPT)CrO(O2)21? in CHCl3 has been studied. The reaction produces the corresponding sulphoxides in nearly quantitative yields according to a 2:1 stoichiometry of sulphide to metaldiperoxide. A second-order-overall (order one in each of the reagents) kinetic law is obeyed. In parallel, the oxidation of organic sulphides by (HMPT)MoO(O2)21' has been studied. Kinetic data, the observed rate laws, and the effect of inhibitors (HMPT, DABCO) have pointed out that-although 1' is significantly more reactive than 1?--considerable similarity exists between the two metaldiperoxides, in that both appear to act as electrophilic oxidizers. Also, through 1H, 31P and 13C NMR investigations have permitted to assess the relevance of equilibria (HMPT)MO(O22 MO(O2)2 + HMPT [with M = Mo(VI) or Cr(VI)]in solution, whereas no NMR evidence could be found for significant substrate coordination under the given conditions.
Mechanisms of peroxidic oxygen transfer to organic substrates : Oxidation of organic sulphides by chromium(vi)oxide diperoxide
Sergio Giannattasio;
1984
Abstract
The oxidation of organic sulphides (n-Bu2S, PhSCH3, Tolyl-SCH3, p-Cl-C6H4SCH3, and Ph2S by (HMPT)CrO(O2)21? in CHCl3 has been studied. The reaction produces the corresponding sulphoxides in nearly quantitative yields according to a 2:1 stoichiometry of sulphide to metaldiperoxide. A second-order-overall (order one in each of the reagents) kinetic law is obeyed. In parallel, the oxidation of organic sulphides by (HMPT)MoO(O2)21' has been studied. Kinetic data, the observed rate laws, and the effect of inhibitors (HMPT, DABCO) have pointed out that-although 1' is significantly more reactive than 1?--considerable similarity exists between the two metaldiperoxides, in that both appear to act as electrophilic oxidizers. Also, through 1H, 31P and 13C NMR investigations have permitted to assess the relevance of equilibria (HMPT)MO(O22 MO(O2)2 + HMPT [with M = Mo(VI) or Cr(VI)]in solution, whereas no NMR evidence could be found for significant substrate coordination under the given conditions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
