Au-Catalyzed Synthesis of Thiopyrano­[2,3‑b]­indoles Featuring Tandem Rearrangement and Hydroarylation

Gold­(III)-catalyzed synthesis of 14-π electron heteroaromatic thiopyrano­[2,3-b]­indole is reported using conjugated enyne tethered indole sulfides, featuring skeletal rearrangement conjoined with intramolecular hydroarylation (via C3–H functionalization of the indole core) and oxidative aromatization. Subsequent Pd-catalyzed C–C coupling resulted in a 16-π electron heteroaromatic isothio­chromeno­[1,8,7-bcd]­indole.