Sulfur dichloride (SCl2)

Structure and properties

The molecule is bent, with sulfur at the center and two bonded chlorine atoms plus lone pairs on sulfur that influence its geometry. It is a covalent compound rather than an ionic salt; the chlorine atoms are covalently bound rather than present as free chloride ions. Physical and chemical properties include pronounced reactivity toward nucleophiles and a tendency to hydrolyze.

Preparation and reactions

Sulfur dichloride is typically produced by controlled chlorination of elemental sulfur or by further chlorination of disulfur dichloride. It can decompose to related sulfur chlorides under certain conditions and reacts readily with water to give hydrogen chloride and sulfur-containing products. It also serves as a chlorinating agent and a source of electrophilic sulfur in synthesis. For more on synthesis steps see methods.

Uses and examples

• Intermediate in the manufacture of organosulfur compounds and specialty chlorosulfur reagents.
• Reagent for introducing sulfur-containing functional groups in organic chemistry.
• Research reagent in small-scale laboratory syntheses.

Practical handling protocols and typical applications are discussed in industrial and laboratory references: safety data and technical notes.

Safety and related compounds

Sulfur dichloride is corrosive, lachrymatory and toxic; it must be kept dry and handled under inert atmosphere because it reacts with moisture to produce acidic and sometimes polymeric sulfur products. It is chemically related to disulfur dichloride (S2Cl2) and other sulfur halides; see comparisons for distinctions and typical behaviors.