• Journal of the Korean Chemical Society
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• v.46 no.6
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• pp.581-584
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• 2002

• Journal of the Korean Chemical Society
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• v.49 no.4
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• pp.363-369
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• 2005

• YAKHAK HOEJI
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• v.44 no.4
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• pp.325-333
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• 2000

The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxides 2 with 2-chloroacrylonitrile gave the 2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxalines 3, which were converted into the 2,3,4,6-tetrahydro-1H-1,2-diazepino[3,4-b]quinoxalines 5-7. The reaction of compounds 3 with selenium dioxide in acetic acid/water resulted in ring transformation to give the 1,4-dihydro-4-oxopyridazino[3,4-b]quinoxalines 8.

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.385-393
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• 2004

2-Ethoxycarbonyl-3-methylquinoxaline 1,4-dioxide (8) was synthesized from benzofuroxan and ethyl acetoacetate. The reaction of compound 8 with hydrazine hydrate or selenium dioxide gave 2-hydrazinocarbonyl-3-methylquinoxaline 1,4-dioxide (9) or 2-ethoxycarbonyl-3-formylquinoxaline 1,4-dioxide (10), respectively. The reaction of compound 9 with alkanoyl chlorides, benzoyl chlorides, heteroacyl chlorides, and benzenesulfonyl chlorides afforded 3-methyl-2-(substituted hydrazinocarbonyl)quinoxaline 1,4-dioxides (11-14), respectively. The reaction of compound 9 with sodium azide gave 2-azidocarbonyl-3-methylquinoxaline 1,4-dioxide (15), and then its refluxing in dioxane/alcohols resulted in the Curtius rearrangement to give N-(3-methyl-1,4-dioxoquinoxalin-2-yl)-alkyl carbamates (16). The reaction of compound 15 with substituted anilines afforded 2-(3-substituted phenylureido)-3-methylquinoxaline 1,4-dioxides (17). The reaction of compound 10 with benzoic hydrazide or substituted anilines provided quinoxaline 1,4-di-oxides (18, 19), respectively. The herbicidal and fungicidal activities of the synthesized compounds were investigated.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.229-236
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• 2000

The reaction of 6-chloro-2-hydrazinoquinoxaline 4.oxide(10) with acetylacetone or dibenzoylmethane gave 6-chloro-2-(3,5-disubstituted pyrazol-1-yl)quinoxaline 4-oxides (11) through the intramolecular·cyclization.The chlorination of compound 11 with phosphoryl chloride afforded 3,6-dichloro-2-(3,5-disubstituted pyrazol-1-yl)quinoxalines (12), whose reaction with hydrazine hydrate provided 6-chloro-3-hydrazinodehydes, benzenesulfonyl chloride, substituted benzoyl chlohdes or acyl chlorides gave novel pyrazolylquinoxalines (14-17).