109002-28-0Relevant academic research and scientific papers
Fused Nitrogen-Containing Heterocycles: IV. 3-Benzoyl-2-oxo-1,2- dihydroquinoxaline Hydrazones and Flavazoles Derived Therefrom
Mamedov,Kalinin,Gubaidullin,Rizvanov,Chernova,Doroshkina,Litvinov,Levin
, p. 131 - 140 (2003)
3-Benzoyl-1,2-dihydroquinoxalin-2-one reacts with hydrazine and thiosemicarbazide to give the corresponding hydrazone and thiosemicarbazone. The reaction with arylhydrazines yields 3-(α-arylazobenzylidene)-1,2,3,4- tetrahydroquinoxalin-2-ones which are tautomeric to the respective arylhydrazones. On heating in boiling acetic acid, the products of both types undergo intramolecular cyclocondensation with formation of 3-phenylpyrazolo[3,4- b]quinoxalines (3-phenylflavazoles). 3-Benzoyl-1,2-dihydroquinoxalin-2-one thiosemicarbazone gives rise to flavazole structure only in the presence of methyl 3-chloro-2-oxo-3-phenylpropionate as a trap of thiocarbamoyl moiety. The cyclization of 3-(α-hydrazonobenzyl)-1,2-dihydroquinoxalin-2-one is accompanied by formation of quinoxalyl ketone azine.
Phenylation and Dephenylation Reactions: Formation of 1H-Pyrazoloquinoxalines
Pillai, P. Madhavan,Ramabhadran, P.
, p. 901 - 904 (2007/10/02)
1,3-Diphenyl-1H-pyrazoloquinoxaline (9) has been isolated as a byproduct in the conversion of quinoxaline-2-carboxaldehyde phenylhydrazone (1) into 1-phenyl-1H-pyrazoloquinoxaline (5) using stored phenylhydrazine as the dehydrogenating agent
