Photoisomerization and photodegradation of metanilic acid

Abstract

The photolysis of metanilic acid (1) as the sodium metanilate, through quartz under helium at λ= 254 nm leading to the isomeric anilinesulphonic acids (2 and 3) and aniline (4) has been studied in water. The effects of pH and solvent on products, the acid–base catalysis of the photoreaction (pH–product profile) and the effects of substrate concentration, radical scavenging, triplet sensitization and quenching studies are reported.

A mechanism involving a single triplet and a series of σ-complexes is proposed.