Reactions of pentafluorobenzoylpyruvic ester and its copper(II) chelate with dinucleophiles
作者:V.I. Saloutin、S.G. Perevalov
DOI:10.1016/s0022-1139(99)00060-3
日期:1999.6
dinucleophiles — hydrazine, phenylhydrazine, hydroxylamine hydrochloride, 1,2-ethylenediamine, 1,2-phenylenediamine, 2-aminophenol — to form heterocyclic compounds. Reactions between bis(ethyl pentafluorobenzoylpyruvate)copper (II) chelate and these amine hydrochlorides also produce heterocycles. The analytical data of these compounds — elemental analysis, IR-, and NMR spectral data — are reported.
Nitrogen-substituted 4-oxoquinoline-2-carboxylic acids have been prepared by the reaction of pentafluorobenzoylpyruvic acid with isopropyl-, cyclohexyl-, phenyl- and ethanol-amine. Ammonia and triethylamine, however, were found to react with pentafluorobenzoylpyruvic acid to form only the 2-carboxy-5,6,7-8-tetrafluorochromone; such behaviour has been found in the reactions of ethyl pentafluorobenzoylpyruvate
A stable crystalline hydrogen-bonded adduct of dimethylsulphoxide (DMSO) and 7-hydroxy-5,6,8-trifluoro-2-carboxychromone has been prepared by the reaction of 2-carboxy-5,6,7,8-tetrafluorochromone with KOH/glycerol in DMSO. It has been found that pentafluorophenol and also 1-cyclohexyl-7-hydroxy-5,6,8-trifluoro-4(1H)-4-oxoquinoline-2-carboxylic acid form the corresponding crystalline hydrogen-bonded
The self-condensation of ethyl pentafluorobenzoylacetate leads to the formation of 3-pentafluorophenyl-1H-isopyrono[2,3-b]-6,7,8,9-tetrafluorochrom in 37% yield. On hydrolysis, this gave 2-pentafluorobenzoylmethyl-5,6,7,8-tetrafluorochromone. Other routes for preparing some new fluorinated chromones have been confirmed via intramolecular cyclization of ethyl pentafluorobenzoylpyruvate and also from the 2-ethoxymethylene pentafluorobenzoylacetic ester.
Saloutin; Perevalov; Skryabina, Russian Journal of Organic Chemistry, 1996, vol. 32, # 9, p. 1340 - 1343