E. V. Pimenova, Olga P. Krasnych, E. Goun
Jun 1, 2003
Citations
0
Influential Citations
9
Citations
Journal
Journal of Fluorine Chemistry
Abstract
Abstract 2-Hydroxy-4-oxo-4-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-but-2-enoic acid methyl ester ( 1 ) was synthesized by the reaction of pentafluoroacetophenone with dimethyl oxalate in the presence of sodium methylate. Subsequently, reactions of compound 1 with aniline, o -phenylenediamine, and o -aminophenol were investigated. In addition, the thermal cyclization of ester 1 was studied and led to the formation of 5,6,8-trifluoro-7-methoxy-4-oxo-4H-chromene-2-carboxylic acid methyl ester ( 6 ) due to nucleophilic substitution of the 3-fluoro group. Hydrolysis of compound 1 and subsequent cyclization by treatment with SOCl 2 gave 5-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-furan-2,3-dione ( 3 ). Thermal decarbonylation of compound 3 under mild conditions resulted in the formation of 3-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-propene-1,3-dione ( 4 ) which dimerized to pyranone 5.