| 摘要 |
Method comprises: (a) reacting a metal hypochlorite or periodate in presence of catalytic amt. of ruthenium salt e.g. ruthenium trihydrate trichloride in alkaline medium to give ruthenium tetraoxide and (b) oxidising cpd. (I) or (II) with ruthenium tetroxide in two-phase system of water/organic solvent e.g. chloroform so that the ruthenium tetroxide, generated in the aq. phase passes to the organic phase, where it oxidises the thioether or sulphoxide and the redn. prod. of the ruthenium tetroxide passes to the aq. phase to reoxidise, to give cpd. (III). Reaction temp. is 0 deg.C to ambient temp. - In formulae, R is H, 2-phthalidyl and others X and Y are H, Cl, Br or I and Z is H or Cl.
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