CONFORMATIONAL INVESTIGATION OF DIARYLSULPHONES BY KERR EFFECT AND DIPOLE-MOMENT METHODS

Molar Kerr constants and electric dipole moments are reported for (C6H5)2SO2, (4-Cl-C6H4) (C6H5)SO2, (2,4,6-Me3C6H2) (4'-BrC6H4)SO2, (4-NO2C6H4)2SO2, (4-MeOC6H4) (4'-NO2C6H4)SO2, (2-MeOC6H4) (4'-NO2C6H4)SO2, (2-NO2C6H4) (4'-MeOC6H4)SO2 and (2-MeOC6H4) (2'-NO2C6H4)SO2 as solutes in dioxane solution at 298 K. The data are analysed in terms of the preferred conformations adopted in solution. In most cases these data are consistent with the presence, in dioxane, of orthogonal or planar-orthogonal conformers, or of a mixture of them. In the orthogonal rotamer both aromatic rings are approximately perpendicular to the C(Ar-) S-C(Ar) molecular reference plane whereas in the planar-orthogonal conformer one ring is coplanar and the other is orthogonal to the reference C(Ar)-S-C(Ar) plane.