Expedient Access to 2‐Benzazepines by Palladium‐Catalyzed C−H Activation: Identification of a Unique Hsp90 Inhibitor Scaffold

: Bioactive 2-benzazepines were accessed in an atom- and step-economical manner through a versatile palladium-catalyzed C-H activation strategy. The C-H arylation required low catalyst loading and a mild base, which was reflected by a broad scope and high functional-group tolerance. The benzotriazolodiazepinones were identified as new heat shock protein 90 (Hsp90) inhibiting lead compounds, with considerable potential for anti-cancer applications.