Sulfur: Organic PolysulfanesBased in part on the article Sulfur: Organic Polysulfanes by Ralf Steudel & Monika Kustos which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.

Abstract

Organic polysulfanes are compounds of the type RS n R with n > 2. They may be chain‐like or cyclic. The organic residues (alkyl or aryl) are linked to the sulfur atoms via carbon atoms. In the literature these compounds are often termed as organic polysulfides, but the IUPAC recommended nomenclature is polysulfanes. Sulfur‐rich organic polysulfanes can be viewed as intermediates between organic and inorganic compounds. On one hand, they are characterized by organic substituents R, which terminate the sulfur chain or close this chain to form a ring. On the other hand, compounds with sulfur chains of three or more sulfur atoms are ‘inorganic’ enough to attract the interest of inorganic chemists who have contributed much to this area. Organic polysulfanes with up to 16 sulfur atoms in the molecules have so far been obtained as pure substances, but species with up to 35 sulfur atoms in a chain or ring have been prepared in mixtures. Organic polysulfanes play an important role not only in basic research and industry, they are also found as natural products in organisms and occur in the inanimate nature. The main importance of organic polysulfanes comes, however, from their role in the large scale industrial vulcanization of natural and synthetic rubber. In this article, the preparation, structure, modern analysis, basic reactions, natural occurrence, biological activity, and practical importance of organic polysulfanes with three or more neighboring sulfur atoms in a chain or ring have been presented.