Nitrogen Chlorosulphide, N₄S₄Cl₂

Nitrogen Chlorosulphide, N₄S₄Cl₂, is obtained by the action of chlorine on nitrogen sulphide, N₄S₄, either in chloroform solution or suspended in carbon tetrachloride. The chlorosulphide is a yellow, crystalline solid, unstable in moist air; it is also unstable when kept under carbon tetrachloride, but crystallises from hot dry benzene without decomposition. It decomposes on heating with formation of some sulphur monochloride and nitrogen. The sulphur chloride formed may reunite with part of the chlorosulphide to form the stable compound, trithiazyl chloride, N₃S₃Cl. This change takes place rapidly at 100° C. Water decomposes nitrogen chlorosulphide according to the equation:

N₄S₄Cl₂ + 8H₂O = 4NH₄Cl + 4SO₂.

The chlorosulphide is reconverted into nitrogen sulphide by the action of cold ammonia. When treated with dry hydrogen chloride in benzene solution it yields a bright yellow compound which is only slightly decomposed by cold water but immediately by lukewarm water.