A metal-free, hypervalent iodine(III)-induced tandem oxidative cycloisomerization based process for preparation of fluorescent diethyl 5,5′-diaryl-2,2′-bifuran-4,4′-dicarboxylates

A new method has been developed for concise synthesis of diethyl 5,5′-diaryl-2,2′-bifuran-4,4′-dicarboxylates. The preparative pathway begins with bis-C-alkylation reaction of the β-ketoester and 1,4-dibromobut-2-yne followed by hypervalent iodine (III)-mediated oxidative cycloisomerization reaction of the formed symmetric γ-alkynyl-diketones. The novel diethyl 5,5′-diaryl-2,2′-bifuran-4,4′-dicarboxylates, formed by using this process were found to possess unique fluorescence properties.