Synthesis in the Key of Catellani: Norbornene-Mediated ortho C–H Functionalization

Abstract

In the late 1990s Catellani reported a remarkable palladium-catalyzed domino reaction [1] in the presence of norbornene, in which aryl iodides were alkylated at the ortho positions by alkyl halides followed by a Mizoroki-Heck reaction to afford products of type 1 (Scheme 1) [2–4]. The process allowed for the construction of up to three carbon–carbon bonds in a single reaction using simple, commercially available starting materials. We called this process the Catellani reaction, and in the past decade considerable attention has been focused upon unlocking its synthetic potential. This review will primarily focus upon the mechanistic aspects of the Catellani reaction, followed by an overview of the synthetic scope of molecules currently accessible with this technology.