The emergence of sulfoxide and iodonio-based redox arylation as a synthetic tool (Review-Digest)

This digest highlights the emergence of the directed metal-free arylation approach employing simple sulfoxide and hypervalent aryliodane. These new processes are characterized by an unusual, and synthetically attractive, retention of the reduced −SR and iodine fragment ortho to the newly formed CC bond. Although the development of the sulfur- and iodane-based methods have occurred independently, it is becoming increasingly obvious that the two processes are highly analogous in terms of the mechanism and the substrate scope. Indeed, both types of reaction are proposed to occur via a [3,3]-sigmatropic Claisen-type rearrangement, and have been carried out on closely related families of substrates. The digest covers the progress made in 2011–2015 both in the sulfoxide-based methods and in the iodane-based reaction. The ultimate goal is to (a) highlight the synthetic potential of the approach; and (b) offer, for the first time, a unified vision of the two processes.