Reactions of Sulphur Fluorides

The work of this thesis is concerned with the reactions of thionyl fluoride, thionyl tetrafluoride and its derivatives, and sulphuryl chloride fluoride. The reactions of thionyl fluoride have been little investigated, and usually involve forcing conditions. Many of the derivatives have been made before, but little is known of their spectroscopic properties. Particular interest was centred on the effect of attached substituents to sulphur on SO, in the derivatives of thionyl fluoride. The 1H n. m. r. of the compounds, R2NS(O)X (R = Me, Et, i-Pr; X = F, Cl, OR, NR2), have been investigated over the temperature range +150 to -110. The halosulphinamides, R2NS(O)X (R = Me, Et, i-Pr; X = F, Cl), show non-equivalence in the 1H n. m. r. spectrum at low temperature, and the alkoxysulphinamides, R2NS(O)OCH2CH3 (R = Me, Et), show evidence of AB coupling in the methylene signals of the ethoxy group. The possible effects which give rise to these phenomena are discussed. The reactions of thionyl tetrafluoride with silicon oxygen compounds have been investigated at length. Phenoxysulphur oxytri-fluoride, PhOS(O)F3, is obtained in good yield from the one to one reaction of SOF4 and Me3SiOPh. The compound, however, is unstable and decomposes on standing. The influence of substitution in the aromatic ring on the stability of the ArOS(O)F3 compounds (Ar = aryl), is discussed. Thus, m-FC6H4OS(O)F3 is very stable, and only partially decomposes on heating at 130. Higher substituted derivatives of thionyl tetrafluoride have been made, and the stability and spectro scopic properties of these compounds are discussed. The preparation of derivatives of the aryloxysulphur oxy-trifluorides in which single bond formation was maintained, did not meet with success. PhOS(O)F3 and Me3SiOEt react to form PnOSO2F, which is thought to be given via PhO(EtO)S(O)F2 as an intermediate. The derivatives, MeN=S(=O) (F)OAr (Ar = Ph, m-FC6H4), are obtained from (Me3Si)2 NMe and ArOS(O)F3 as stable compounds which are not air sensitive. Reactions of sulphuryl chloride fluoride involve preferential cleavage of the sulphur fluorine bond, although sulphur chlorine bonds are more labile. Factors which influence these reactions are discussed. Addition reactions across C=O and C=C bonds did not succeed with sulphuryl chloride fluoride, although other sulphuryl compounds are known to partake in such reactions