Chiral discrimination and isomerization processes in monomers, dimers and trimers of sulfoxides and thioperoxides
The chiral discrimination in cyclic dimers and trimers of mono-substituted sulfoxides and thioperoxides has been studied by means of DFT (B3LYP/6-31+G**) and ab initio (MP2/6-311+G**) calculations. In addition, the inter- and intramolecular proton transfer processes that interconvert these two classes of compounds have been considered for the isolated molecules and clusters. The thioperoxide clusters are more stable than the corresponding sulfoxides even though the strongest hydrogen bonds are found in the latter complexes. Correlations have been found between the relative energies of the sulfoxide versus the thioperoxide compounds and the transition state barriers. The geometry of the hydrogen bonds has been analyzed using a Steiner–Limbach relationship.