Abstract
The oxidation of 5-nitrocinnoline (I) with hydrogen peroxide in acetic acid, and with persulfuric acid in sulfuric acid afforded 5-nitrocinnoline 1-oxide (II), 5-nitrocinnoline 2-oxide (III), and 4-nitroindazole (IV). The Oxidation of 8-nitrocinnoline (V) with hydrogen peroxide in acetic acid, with hydrogen peroxide, with phthalic monoperacid, with hydrogen peroxide in 10% sulfuric acid, and with persulfuric acid in sulfuric acid afforded 8-nitrocinnoline 2-oxide (VI), 7-nitroindazole (VII), and 8-nitro-4-cinnolinol (VIII). On the other hand, the oxidation of V with chromic acid in acetic acid gave only VIII with recovery of V.
