Proximity effects in diaryl derivatives. Part VI. Base-catalysed rearrangement of 2-(hydroxyamino)aryl aryl sulphones to 2-hydroxy-2′-(arylsulphonyl)azoxybenzenes

Abstract

Treatment of 2-(hydroxyamino)aryl phenyl sulphones or bis-(2-hydroxyaminoaryl) sulphones with aqueous sodium hydroxide at 20° gives 2-hydroxy-2′-(arylsulphonyl)azoxybenzenes (V) and (VII) and arenesulphonate anions. The hydroxy-group in the azoxy-product is derived from the sulphone or hydroxyamino-groups and not from the added base. 2-Nitrosoaryl phenyl sulphones, 2,2′-bis(arylsulphonyl)azoxybenzenes, and 2-nitrosophenols are shown not to be intermediates.