32387-89-6

Upstream product

• 116611-89-3 7-amino-5-methoxy-2,3-diphenylquinoxaline 
• 134-81-6 benzil 
• 21268-85-9 2-amino-1-methoxy-3,5-dinitrobenzene 

Downstream Products

• 116588-13-7 <5-(2,3-diphenyl)-quinoxalyl> dimethyl phosphate 
• 102468-03-1 acetic acid-(2,3-diphenyl-quinoxalin-5-yl ester) 

Relevant academic research and scientific papers

Synthesis of quinoxalines by cyclization of α-arylimino oximes of α-dicarbonyl compounds

Heating the title compounds 1 at reflux in acetic anhydride yields quinoxalines 3 and 4 via a presumed aryliminoiminyl radical 5, resulting from homolytic cleavage of the N-O bond in the intermediate ester 2. The observed regioselectivity of the reaction is also rationalized by implicating such a radical. (C) 2000 Elsevier Science Ltd.

An unexpected course of the Meisenheimer reaction : aryl phosphates in the reaction of phosphoryl chloride with 2,3-diphenylquinoxaline-N1-oxide.

Contrary to what is observed with other ?-deficient heteroaromatic N-oxides, the reaction of 2,3-diphenylquinoxaline-N1-oxide with OPCl3 gives only very poor yields of chlorinated quinoxalines.It is shown that the major product arises from an unprecedented attack by the nucleophilic oxygen atom of the reagent at a carbon atom of the homocycle of the O-phosphorylated N-oxide, leading ultimately to the corresponding mono- (or di-) aryl ester of phosphoric acid.Using a much smaller excess of OPCl3 and dilution of the medium with an inert solvent strongly increase the yield of chlorination products.It is suggested that, after the initial O-phosphorylation, phosphate formation might be the primary step in all the Meisenheimer reactions.