A theoretical study of the sulfenate-sulfoxide rearrangement. Effect of the hydrogen bond complexation
A DFT study of the thermal and radical sulfenate–sulfoxide rearrangement of derivatives of 3-propenyl sulfoxide has been carried out. The effect of the substitution and hydrogen bond complexation has been analyzed. The results show that without external factors the radical breakdown path is the one preferred by the alkyl and aromatic derivatives while the unsubstituted system proceeds preferentially through a two-step series of [1,3]- and [2,3]-sigmatropic shifts. The inclusion of a hydrogen bond donor interacting with the oxygen atom increases the stability of all the species except the radical and the final products. Thus, in the dimethyl derivative the radical and two-step processes present similar limiting steps. The analysis of the electron density of the systems provides some relationships between the properties at the bond critical point and the interatomic distances for the S···C and H···O cases.