The synthesis and reactions of some polychloroaromatic azides, sulphonyl azides and sulphonohydrazides

Azidopentachlorobenzene (2) and 4-azidotetrachloropyridine (4) react with norbornene to give the aziridines (6) and (7); with cyclohexene the enamines (10) and (11) are formed. 1,2,3,4-Tetrachlorobenzene reacts with chlorosulphonic acid to give 2,3,4,5-tetrachlorobenzenesulphonyl chloride (14), but the reported chlorosulphonation of 1,2,4,5-tetrachlorobenzene could not be effected, and under drastic conditions the reaction afforded hexachlorobenzene. The sulphonyl chloride (14) reacts with hydrazine to give the sulphonohydrazide (15). However, in contrast to previous work, reaction of polychloroaromatic sulphonyl chlorides with ammonia and phenylhydrazine gave only the normal sulphonamides and N'-phenyl sulphonohydrazides.