Thiocarbonyl Chloride, CSCl₂

Thiocarbonyl Chloride, Carbon Dichlorosulphide, or Thiophosgene, CSCl₂, is produced by the prolonged action of dry chlorine on carbon disulphide:

CS₂ + 2Cl₂ = SCl₂ + CSCl₂,

or by passing mixed carbon tetrachloride and hydrogen sulphide vapours through a red-hot tube:

CCl₄ + H₂S = CSCl₂ + 2HCl.

It may also be obtained by reduction of carbon tetrachlorosulphide, CSCl₄, with tin and hydrochloric acid.

The chloride is a red, mobile liquid, with a suffocating odour. It has a density of 1.5085 at 15° C., and boils at 73.5° C. It fumes in moist air and is decomposed by water or alkalis, forming carbonic and hydrochloric acids or their salts and hydrogen sulphide.