Cyclic sulphur inides and thiazenes: synthetic studies and some structural correlations

Abstract

This thesis describes the work carried out by the author between September 197^ and September 1977. The shapes of known sulphur-nitrogen species are rationalised by linear interpolation and the probable structures of sulphur- nitrogen species, as yet uncharacterised, are discussed. Correlations between sulphur-nitrogen and sulphur-oxygen stretching frequencies and bond lengths are presented and predictions of shapes from infrared data are discussed. Preparation of derivatives of sulphur chlorides using methyleneamino-lithium proved to be an excellent route to old and new sulphur-nitrogen compounds. Reactions of (SNCl)(_3) were studied with a view to reaction mechanisms involved and the first fully characterised derivatives of 3-phenylcyclodithiadiazolium chloride were prepared. The reactions of sulphur-nitrogen-oxygen species especially hexaoxocyclotrithiazenide (3-) anions are reported including the preparation of new salts. Attempts were made to prepare new members of the "electron rich" aromatic series of sulphur nitrogen compounds. Although unsuccessful in the original aim, the new compounds S(_7)NCOCF(_3), (S(_5)N(_5)) (SnCl(_5)(OPCl(_3))) and S(_4)N(_4).POCl(_3).SnCl(_4) were prepared and the use of phosphoryl chloride as a solvent was investigated. The crystal structure of (SnCl(_5)(OPCl(_3))) is discussed and a series of CNDO/2 calculations with and without "d" orbital basis sets have been carried out on a series of "aromatic" sulphur-nitrogen compounds.