Abstract
A reaction mechanism of the oxidation of quinoline to ο-nitrobenzoic acid with hydrogen peroxide was suggested. In the mechanism, the main intermediates were quinoline 1-oxide, carbostyril 1-oxide, 2-nitrosocinnamic acid and 2-nitrocinnamic acid. It was experimentally confirmed that the oxidation of 2-position of quinoline 1-oxide in acidic medium and oxidative deoxidation of quinoline 1-oxide and carbostyril 1-oxide took place during the hydrogen peroxide treatment. In a restricted oxidation with hydrogen peroxide, quinoline was oxidized to 3-quinolinol and quinolinium sulfate afforded 5-quinolinol.
