Expeditious Access to Functionalized Tricyclic Pyrrolo-Pyridones via Tandem or Sequential C–N/C–C Bond Formations

The facile synthesis of both saturated and unsaturated tricyclic pyrrolo-pyridones starting from a single readily available, common monocyclic reagent has been developed. An intermolecular annulation via a tandem Buchwald–Hartwig/Heck reaction led to the synthesis of β-carbolinones. The analogous semisaturated tricyclic pyrrolo-pyridones were prepared in good to excellent yields by sequential Buchwald–Hartwig and Fischer indole reactions. The methods feature mild reaction conditions and good functional group tolerance.