The approach to 3-(furan-2-yl)-1,3-di(het)arylprop-2-en-1-ones based on the oxidative dearomatization of 3-(furan-2-yl)-1,3-di(het)arylpropan-1-ones followed by an unusual cyclization of the formed di(het)aryl-substituted 2-ene-1,4,7-triones has been developed. The cyclization step is related to the Paal–Knorr synthesis, but the furan ring formation is accompanied in this case by a formal shift of the double bond through the formation of a fully conjugated 4,7-hydroxy-2,4,6-trien-1-one system or its surrogate.

A synthetic approach to furyl- and benzofuryl-containing building blocks utilizing easily accessible substrates is reported. Cascade acid-catalyzed reactions of 2-methylfuran with α,β-unsaturated carbonyl compounds or salicyl alcohols followed by oxidation afford functionalized furans and benzofurans, respectively. Synthetic potential of the obtained products was demonstrated by synthesizing hetaryl-substituted heterocycles, which may find an application in materials chemistry.

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