Accession Number : AD0784704

Title :   Aromatic Nucleophilic Substitution with Sulphoxides: The Interaction of Dimethyl Sulphoxide with Chloronitrobenzenes,


Personal Author(s) : Biffin,M. E. C. ; Paul,D. B.

Report Date : 20 NOV 1973

Pagination or Media Count : 12

Abstract : Activated chlorine atoms are displaced by sulphoxide oxygen when di- and tri-nitrochlorobenzenes are heated in dimethyl sulphoxide. The corresponding phenols, thiomethoxymethyl- and formyl-substituted phenols, thioanisoles and decomposition products of chlorodimethyl sulphide are formed. Monochloronitrobenzenes do not undergo reaction with Me2SO even at 190C, but in the presence of added sodium acetate or sodium benzoate, phenols and thioanisoles are obtained together with products derived from the sulphonium ylid CH3S(+)=CH2. The observations are rationalized mechanistically. The reaction mixtures are shown to oxidize benzyl alcohol to benzaldehyde. These results do not substantiate the presence of an intermediate sulphonium complex, however, because benzyl alcohol competes more favourably for the chloroaromatic system than does Me2SO; benzyl alcohol forms the chloride which then undergoes a Kornblum oxidation to yield benzaldehyde. (Author)

Descriptors :   *Substitution reactions, Nitrobenzenes, Sulfoxides, Chlorine compounds, Australia

Subject Categories : Organic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE