The Chemical and Physical Properties of Polychalcogens

The optimized synthesis of acyclic dialkoxydisulfides and aromatic polysulfides is described andtheir physical properties probed. In particular, theorigin of the high barrier to rotation in thedialkoxy disulfides was determined to be due to ageneralized anomeric effect. The origin of the highrotational barrier was also verified experimentally. Complimentary to this thermal process, thedecomposition of dialkoxy disulfides was alsoinvestigated. Theoretical modeling on the relative ground stateenergies of dialkoxy disulfides is also described. It has been ascertained that the equilibrium positionbetween the two isomers can be influenced by the ringsize of the molecule; larger rings promote thedialkoxy disulfide isomer. These modeling studieswere successfully corroborated experimentally. The kinetics of desulfurization of acyclic aromatictri- and tetrasulfides is described. Tetrasulfideswere found to transfer a sulfur atom totriphenylphosphine over ten times faster than theirtrisulfide analogues.