Norbornadiene Serves as a Tolyl Group Precursor for Constructing Biphenyl Derivatives by Palladium Catalysis

We herein report a Pd(0)-catalyzed Catellani-type reaction of aryl iodides, O-acylhydroxylamine, and norbornadiene (NBD), where NBD acts as an o-tolyl synthon to efficiently afford aminobiphenyl derivatives. The key to this transformation is a rare β²-carbon elimination of the norbornyl Pd(II) intermediate rather than the classic β¹-carbon elimination, making this the first example of NBD as an aromatic synthon in a Catellani-type reaction.