Synthesis of α,β-Unsaturated N-Sulfonyl Imides through Zinc-Catalyzed Intermolecular Oxidation of N-Sulfonyl Ynamides.

A novel zinc-catalyzed intermolecular oxidation of N-sulfonyl ynamides has been developed. A variety of functionalized α,β-unsaturated N-sulfonyl imides are readily accessed by utilizing this approach, thus providing a viable alternative to synthetically useful α,β-unsaturated imides. Importantly, the reaction is proposed to proceed by a vinyligous E2-type elimination pathway, but not metal carbene pathway.

Generation of α-Imino Gold Carbenes through Gold-Catalyzed Intermolecular Reaction of Azides with Ynamides.

The generation of α-imino gold carbenes via gold-catalyzed intermolecular reaction of azides and ynamides is disclosed. This new methodology allows for highly regioselective access to valuable 2-aminoindoles and 3-amino-β-carbolines in generally good to excellent yields. A mechanistic rationale for this tandem reaction, especially for the observed high regioselectivity, is supported by DFT calculations.

Flexible and practical synthesis of 3-oxyindoles through gold-catalyzed intermolecular oxidation of o-ethynylanilines.

A novel gold-catalyzed intermolecular oxidation of o-ethynylanilines has been developed. A range of functionalized 3-oxyindoles are readily accessed by utilizing this strategy. Importantly, this gold-catalyzed oxidative process outcompetes the typical indole formation.