3- Phenylbenzo quinoxaline

Dimethylamino-6-nitro-3-phenylbenzo[/ quinoxaline 4-oxide is formed in a similar reaction from l-methoxy-2,4-dinitronaphthalene with benzacetiniidamide. ... 

Reaction of l-nitroso-2-aminonaphthalene with the aziridine 16 gives a mixture of 3-phenylbenzo[/]quinoxaline (18) and the naphthoimidazole 19. The reaction is initiated by thermal cleavage of the aziridine into the corresponding azomethine 17 and cycloaddition of the azomethine to the nitroso group. Other examples of this type of reaction have been reported. 

There is little systematic knowledge of the chemistry of this ring system. Oxidation of 3-phenylbenzo[/]quinoxaline with chromic anhydride in boiling acetic acid gives 3-phenylbenzo[/]quinoxaline-5,6-quinone (28). The quinone reacts with aromatic aldehydes to form addition products 29 on exposure to light. Reduction of 28 with phenylhydrazine gives the corresponding hydroquinone, which is characterized as a diace-... 

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