3-Heteraglutaraldehydes. Part III. The 1,2-dithian-4,5-diols and tetra-hydrothiophen-3,4-diols and their oxidation by periodate

Abstract

Both isomers of the title diols have been prepared by improved methods. The diacetates of the dithiandiols were readily oxidised to stable, crystalline thiolsulphinates, and with difficulty to thiolsulphonates. Bisdisulphides were formed by reaction of a thiol with the thiolsulphinates. Tris(dimethylamino)phosphine abstracted sulphur from the trans-thiolsulphinate yielding a contracted ring (sulphoxide), whereas tributylphosphine regenerated disulphide by deoxygenation. The dithiandiols reacted readily with Chloramine-T; the trans-compound afforded two isomeric bicyclic sulphenate ester derivatives. Periodate oxidised the tetrahydrothiophendiols to either 3-thia-glutaraldehyde or its 3-oxide, and the dithiandiols to 3,4-dithia-adipaldehyde. The rates of oxidation were compared with those of other cyclic vicinal diols. A number of derivatives were prepared.