Enamino Derivatives of 1,3-Dioxoindane-2-carboxylic Acid
摘要:
Although 1,3-dioxoindane-2-carboxylic acid is highly unstable, its enamino derivatives can be isolated by careful hydrolysis of their esters with 2,4-dihydroxy-1,4-naphthoquinone. Crystal structure determination reveals the formation of two intramolecular hydrogen bonds. offering thus a possible explanation for the stability of these acids.
Indenocarboxamides, resulting from the sequential addition of two arylamine equivalents to indanedione ketene dimer, are oxidized by [bis(trifluoroacetoxy)iodobenzene] to fused indeno-1,4-diazepinones in yields depending on the substituents on both aromatic rings. A plausible reaction pathway explaining the formation of the title compounds, as well as the formation of the two other minor products of the reaction, through a common intermediate, is suggested.