Palladium-catalyzed dearomative 1,4-arylmethylenation of naphthalenes

Abstract

An efficient palladium-catalyzed construction of E-exocyclic-double-bond-containing spirooxindoles via 1,4-arylmethylenation of naphthalenes has been developed. Aryl aldehyde-derived N-tosylhydrazones were successfully applied as carbene precursors to capture the endocyclic π-allylpalladium intermediate, which was generated via an arylative Heck reaction of the naphthalene-masked conjugated diene, followed by a highly regioselective β-hydride elimination. This reaction features broad functional group tolerance and excellent chemo- and E/Z selectivities.