Pyrocatechin readily condenses to form heterocyclic compounds; cyclic esters are formed by phosphorus trichloride and oxychloride, carbonyl chloride, sulphuryl chloride, &c.; whilst ortho-phenylenediamine, o-aminophenol, and o-aminothiophenol give phenazine, phenoxazine and thiodiphenylamine.
Sulphur chloride, S2C12, is obtained as a by-product in the manufacture of carbon tetrachloride from carbon bisulphide and chlorine, and may also be prepared on the small scale by distilling sulphur in a chlorine gas, or by the action of sulphur on sulphuryl chloride in the presence of aluminium chloride (0.
It combines directly with chlorine to form sulphuryl chloride and also with many metallic peroxides, converting them into sulphates.
Sulphuryl fluoride, SO 2 F 2, formed by the action of fluorine on sulphur dioxide (H.
1 3 2, p. 374), is an exceedingly stable colourless gas at ordinary temperatures, becoming solid at about -120° C. Sulphuryl chloride, SO 2 C1 2, first obtained in 1838 by Regnault (Ann.