The Power of Iodane-Guided C−H Coupling: A Group-Transfer Strategy in Which a Halogen Works for Its Money

Hypervalent organoiodane reagents are ubiquitous in organic synthesis, both as oxidants and as electrophilic group-transfer agents. In addition to these hallmark applications, a complementary strategy is gaining momentum that exploits the ability of λ³-iodanes to undergo iodine-to-arene group transfer, for example, via iodonio-Claisen-type rearrangement processes. This Minireview discusses recent advances in the use of this method to access a variety of the C−H-functionalized iodoarenes. While Section 2 is focused on the ortho C−H propargylation, allylation, and the more unusual para C−H benzylation, Section 3 is devoted to the C-arylation of enol and phenol substrates. The accompanying discussion includes mechanistic considerations and goes into the synthetic applications of the final iodoarene cores. The Minireview concludes with further conceptual extensions of the method, including the use of non-conventional coupling partners (for example, cyanoalkylation), improved access to λ³-iodane building blocks, and the development of iterative approaches to polysubstituted iodoarenes.