Nitrosulphonyl Chloride, NO₂.SO₂Cl

The acid chloride structurally derived from nitrosulphonic acid can be obtained by the interaction of thionyl chloride (or less simply chlorosulphonic acid) and silver nitrate:

SOCl₂ + AgNO₃ = AgCl + NO₂.SO₂Cl.

It may also be obtained by the action of nitrosyl chloride on sulphuric anhydride. It is a white, leafy, crystalline mass, somewhat resembling stearic acid in appearance. It is decomposed by moist air with formation of sulphuric, hydrochloric and nitric acids.