Synthesis of 2-(1-alkyl(aryl)-4-oxo-5,6,7,8-tetrafluoro-1, 4-dihydroquinolin-3-yl)glyoxylic acid derivatives

Methods for synthesis of previously unknown 2-(1-alkyl(aryl)-4-oxo-5,6,7,8-tetrafluoro-1,4-dihydroquinolin-3-yl)glyoxylic acids and their esters from the copper chelate of ethyl pentafluorobenzoylpyruvate were developed. 1-Aryl(alkyl)-3-ethoxalyl-5,6,7,8-tetrafluoro-quinolin-4-ones react with o-phenylenediamine and o,-aminophenol to give the corresponding quinolin-3-ylquinoxalones and quinolin-3-ylbenzoxazines. The same heterocycles act with o-aminothiophenol to yield ethyl-2-(7-(2-aminophenylthio)-1-aryl-5,6,8-trifluoro-quinolon-3-yl)-2-(2-mercaptophenylimino)glioxylates. Interaction of 1-aryl-3-ethoxalyl-(heteryl)-5,6,7,8-tetrafluoroquinolones with morpholine gives 7-mono- and 5,7-disubstituted products depending on the reaction conditions. (C) 2001 Elsevier Science B.V. All rights reserved.