Aromatic hydrocarbons nuclear hydroxylation

Substituents exert a powerful influence upon the light effects. The introduction of several hydroxyl groups into aromatic hydrocarbons of one nucleus produces luminous-effects which do not occur with only one hydroxyl group in the molecule. The amino-group always excites luminosity even in mono-nuclear hydrocarbons. The effect of the amino-group often enforces that of the hydroxyl group, thus aminophenols produce luminous effects which are often very intense. 

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