Polyhalogeno-aromatic compounds. Part XV. Preparation and reactions of tetrachloropyridine-4-sulphenyl chloride and tetrachloropyridine-4-sulphonyl chloride

Abstract

Tetrachloropyridine-4-sulphenyl chloride was prepared by treating either tetrachloropyridine-4-thiol or the corresponding disulphide with chlorine in carbon tetrachloride and was shown to react normally with acetone, aniline, and sodium cyanide. Tetrachloropyridine-4-sulphonyl chloride was prepared from the thiol by a modification of the usual procedure. It reacted with aqueous alkali, zinc dust in water, aqueous alkaline sodium sulphite, and various amines to give the sulphonic acid or tetrachloropyridin-4-ol (with a large excess of alkali), the thiol, the sulphinic acid, and the corresponding sulphonamide, respectively. The sulphonic acid and the sulphonyl chloride reacted with phosphorus pentachloride to give pentachloropyridine, whereas the sulphinic acid reacted with chlorine in carbon tetrachloride or acetic acid to give the sulphonyl chloride.