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An unprecedented deconstructive reorganization strategy for the de novo synthesis of hydroxylated benzofurans from kojic acid- or maltol-derived alkynes is reported. In this reaction, both the benzene and furan rings were simultaneously constructed, whereas the pyrone moiety of the kojic acid or maltol was deconstructed and then reorganized into the benzene ring as a six-carbon component. Through this strategy, at least one free hydroxyl group was introduced into the benzene ring in a substitution-pattern tunable fashion without protection-deprotection and redox adjustment. With this method, a large number of hydroxylated benzofuran derivatives with different substitution-patterns have been prepared efficiently. This methodology has also been shown as the key step in a collective total synthesis of hydroxylated benzofuran-containing natural products (11 examples).

The highly chemo-, enantio-, and diastereoselective catalyst-controlled intramolecular allylic C-H insertion and cyclopropanation of donor/donor carbenes are reported. The RuII /Pybox complex selectively catalyzed the intramolecular allylic C-H insertion, providing vinyl-substituted dihydroindoles with greater than 20:1 chemoselectivity and up to greater than 99 % ee. Chiral dirhodium(II) tetracarboxylates, however, selectively promoted the intramolecular cyclopropanation, giving rise to cyclopropane-fused tetrahydroquinoline derivatives in excellent yields with greater than 99:1 chemoselectivity and up to 97 % ee.

A cascade Claisen rearrangement of a well-organized maltol propargyl ether for the construction of polysubstituted salicylaldehydes is reported. This reaction features high atom economy (100 %), as well as catalyst-free and gram-scale conditions. Based on this novel methodology, the total synthesis of hemigossypol, gossypol, and their analogues has been realized.

A one-pot tandem process involving hydrolysis, Knoevenagel condensation, Michael addition, and Conia-ene (HKMC) reactions has been developed for the rapid synthesis of indanone-fused 2-methylene tetrahydrofurans from the reaction of enynals and propynols. In this process, two rings and four bonds are generated with 100 % atom-economy and high step-efficiency. The resulting tetrahydrofurans were readily oxidized into α-methylene γ-lactones, which are one of the most important substructures in natural and bioactive compounds.