6.3.2 Oxyanions

Aryl ethers bearing EWG in ortho and para positions proceed hydrolysis to afford phenols.

6.3.3 Sulfite Ion

Aryl sulphonic acid can be converted, through their salts, to phenols, by alkali fusion. In spite of the extreme conditions, the reaction gives fairly good yields, except when the substrate contains other groups that are attacked by the alkali at the fusion temperature. Milder conditions can be used when the substrate contains activating groups, but the presence of deactivating groups hinders the reaction. The mechanism is obscured but the benzyne intermediate has been ruled out by the finding that the cine substitution does not occur. For example, sodium p -toluenesulfonate with fused sodium hydroxide gives p -cresol at 250-300°C.

6.3.4 Nitrogen Anions

Nitrite ion could be displaced if other nitro groups are present to activate the aromatic nucleus.