ARENEDIAZONIUM o-BENZENEDISULFONIMIDES: SOME KINETICS OF AZO COUPLING REACTIONS WITH NAPHTHOLS

Kinetic investigation of azo coupling reactions between naphthols and 4-methoxy and 4-nitrobenzenediazonium o-benzenedisulfonimides has been carried out for comparison with the related benzenediazonium tetrafluoroborates. The data clearly indicate that the two kinds of diazonium salts show very similar reactivities. This fact emphasized that arenediazonium o-benzenedisulfonimides, which are very stable, may be used as alternatives to the more usual diazonium salts. The azo coupling reactions between 4-nitro- and 4-methoxybenzenediazonium salts and 1-bromo-2-naphthol, performed with equimolar amounts of both reagents, showed the unexpected formation of large amounts of 1-bromo-4-nitrobenzene and 1-bromo-4-methoxybenzene. Some mechanistic implications of this behaviour are discussed.