Structure of Organic Oxygen Compounds of Sulphur

The nature of the sulphur–oxygen bond, the geometry of molecules of the types XYSO, XYSO₂, XSOOH, and XSO₂OH, and the character of the intramolecular interactions in these compounds are discussed. Apart from the σ-bond between sulphur and oxygen, interaction obviously occurs by means of the 3d-orbital of sulphur and the 2p-orbital of oxygen (2p–3d hybridisation). The interaction of a sulphinyl group with the substituents X and Y is not conjugation, but has an induction and electron-acceptor character.
In all oxygen compounds of sulphur the sulphonyl group has a tetrahedral structure with the sulphur atom at the centre of the tetrahedron, in good agreement both with the chemical properties and with the assignment of the modes of vibration of sulphur–oxygen bonds in infrared and Raman spectra. The position ν_SO of the stretching bands is affected only by change in the character and length of the sulphur–oxygen bond with variation in the electronegativity of the substituents X and Y or on passing from ionised to covalent compounds. These properties of the ν_SO absorption bands are explained by the highly specific character of the sulphur–oxygen vibrations. The bibliography contains 139 references.