Theoretical study of inversion rotary barriers and mechanism of automerization of molecules of imines and ilides of tetracoordinated elements of group 6 A

With the aid of SCF MO methods and extended method of Huckel pyramidal inversion and internal rotation (planar inversion) barriers have been calculated in the series of compounds of the type R'R2X=Y, where X=S, Se, Te and Y=O, NH, PH, CH2. Surfaces of potential energy of the automerization reaction are constructed. Connection has been analyzed between the configuration stability of oxides, imines and ilides of sulphur, selenium and tellurium and the nature of the central atom of Group VIA. Tellurium compounds are shown to be characterized by the highest inversion barriers and lowest rotational barriers about the X=Y bond