N-Phenyl-N'-arenesulfonylhydrazine(1-II) on pyrolysis by refluxing in an atmosphere of nitrogen at ca.
240°C give SO,, H,S, MI3, arene. biaryl. aniline, azobenzene, diaryl sulfide, diaryl sulfone, arenesulfonic
acid. phenyl hydrazine and carbazole derivatives. N-Benzylidene-N'-benzenesulfonylhydrazone(III) on
similar treatment gives the previous products in addition to benzonitrile, bibenzyl, stilbene, 2-phenylindole
and 2,3,4,5-tetraphenyIthiophene. The observed results have been interpreted in terms of a free
radical mechanism involving the hornolysis of N-N and S-N bonds