Permanganate Oxidation of Quinoxaline and Its Derivatives

Article abstract of DOI:10.1002/hlca.19940770610

The oxidation reaction of a series of quinoxaline derivatives, using KMnO4 in the presence or absence of NaOH, are described.Neutral oxidation of 2-chloro- and 2,3-dichlorodioxalines 2-4 afforded the corresponding chloro- and dichloropyrazinedicarboxilic acids 13 and 14 in good yield.On the other hand, oxidation of quinoxalin-2(1H)-one and 1,4-dihydroquinoxaline-2,3-dione derivatives in alkaline medium gave different products, with the quinoxalin-2(1H)-one (5) forming 1,4-dihydroquinoxaline-2,3-dione (9), while various substituted quinoxalin-2,3-dione derivatives (see 9-11) gave a new type of dimeric products.The structural assignments for the new compounds were based on spectroscopic data.