2-Chloro-1,3,5-trithiane and 2-Chloro-1,3-dithiane. Their Ionic Dissociation and Reactions with Nucleophiles

Abstract

Abstract 2-Chlorol,3,5-trithiane and 2-chloro-1,3-dithiane have been prepared by chlorination of the corresponding polythianes with N-chlorosuccinimide. These chlorides afford various substitution products when treated with nucleophiles, whereas nuclear substitution of the aromatic ring occurs when the chlorides are treated with phenol or N,N-dimethylaniline. 1H NMR spectra of these chlorides show remarkable solvent dependence which is explained by assuming ionic dissociation of the chlorides to produce polythianyl cation and chloride anion. Free energies of activation for the dissociation in various solvents indicate that the dissociation of 2-chloro-1,3,5-trithiane is more sluggish than that of 2-chloro-1,3-dithiane. The results are attributed to the difference in availability of electrons on the sulfur atoms in two systems.