Organosulphur compounds : XLVII Alkylation of sulphinic acids by o-alkylisoureas: o-versus s-reactivity and asymmetric synthesis of alkyl sulphinates

Abstract

The reaction of 0-alkylisoureas with sulphinic acids was found to produce the corresponding sulphones and sulphinates, the latter being predominantly formed. The sulphinate to sulphone ratio is strongly influenced by the kind of alkyl groups in the 0-alkylisourea and appeared to be also dependent on the solvent used. A few optically active sulphinates (e.e. up to 8.1%.) were prepared in the reaction between benzenesulphinic acid and a series of 0-alkylisoureas bearing optically active substituents at the nitrogen atom. A possible reaction mechanism is discussed.