Expedient Pd‐Catalyzed Α‐arylation Towards Dibenzoxepinones: Pivotal Manske's Ketone for the Formal Synthesis of Cularine Alkaloids

The general synthesis of diversely substituted dibenzoxepinones by a combined Pd-catalyzed alpha-arylation and SNAr strategy is reported and applied to the synthesis of Manske's ketone, a key intermediate en route to the total synthesis of cularine alkaloids. In the course of this work, an unanticipated ring contraction reaction to a xanthone was observed and serves as a caveat for the conditions of the widely used alpha-arylation reaction.