Palladium-Catalyzed Intramolecular Heck Dearomative Alkenylation of Indoles with N -Tosylhydrazones.

An elegant Pd-catalyzed intramolecular Heck dearomative alkenylation of aryl iodides with functionalized N -tosylhydrazones proceeded through a sequential dearomative carbopalladation, migratory insertion, and β-hydride elimination in the presence of Pd(CF 3 COO) 2 (10 mol %), PPh 3 (30 mol %), and Cs 2 CO 3 (2.0 equiv) in 1,4-dioxane (2.0 mL) at 120 °C for 14 h under an argon atmosphere. This cascade cycloaddition protocol provided a reliable and versatile approach to a sequence of structurally diverse indolines in moderate to good yields with good functional group compatibility. In addition, the synthetic robustness of the methodology is highlighted by a scaled-up experiment and derivatization of products via epoxidation and reduction reactions.