Brönsted acid-catalyzed one-pot synthesis of indoles from o-aminobenzyl alcohols and furans has been developed. This method operates via the in situ formation of aminobenzylfuran, followed by its recyclization into the indole core. The method proved to be efficient for substrates possessing different functional groups, including -OMe, -CO2Cy, and -Br. The resulting indoles can easily be transformed into diverse scaffolds, including 2,3- and 1,2-fused indoles, and indole possessing an α,β-unsaturated ketone moiety at the C-2 position.

We report the divergent synthesis of benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans using the concept of the extended Corey-Chaykovsky reactions. With this concept, 2-hydroxychalcones were treated with the Corey ylide providing highly...

Oxidative rearrangement of 2-(2-aminobenzyl)furans affording 2-(2-acylvinyl)indoles in a stereocontrolled manner in good-to-excellent yields has been developed. Thus, (2-aminobenzyl)furans with electron-releasing alkoxy substituents in the phenyl group form only E-isomers of 2-(2-acylvinyl)indoles. Conversely, substrates without such substituents produce target products as Z-isomers exclusively. A short diastereoselective method for the transformation of the obtained 2-(2-acylvinyl)indoles into antimalarial bisindole alkaloid flinderole A-C analogues has been developed.

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The Brönsted acid-catalyzed cascade synthesis of densely substituted benzofurans from easily available salicyl alcohols and biomass-derived furans has been developed. The disclosed sequence includes the intermediate formation of 2-(2-hydroxybenzyl)furans that quickly rearrange into functionalized benzofurans. The established protocol was applied for the total synthesis of sugikurojinol B.

Rhodium-catalyzed decomposition of furyl-tethered 1-sulfonyl-1,2,3-triazoles was demonstrated to have high synthetic potential for the synthesis of densely substituted heterocyclic frameworks.

Recent developments on the transformations of furans under oxidative conditions toward the total synthesis of complex natural compounds are discussed. Reactions and methods are classified according to the type of oxidant used. Comparisons are then made between all the strategies to provide a comprehensive overview. This review covers the most prominent work published from 2011 until 2017.1 Introduction2 Reagents and Methods for Oxidation of the Furan Ring2.1 Singlet Oxygen2.2 Peroxides and Hydroperoxides2.3 Quinones2.4 Halogen-Based Oxidants2.5 Chromium-Based Oxidants3 The Achmatowicz Reaction3.1 Halogen-Based Oxidants3.2 Hydroperoxides3.3 Enzymatic Oxidation4 Conclusion

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