Alkynylation by Electrophilic CH Functionalization

Abstract

The introduction of alkyne scaffolds in organic molecules is an interesting topic for researchers ranging from synthetic organic chemists to materials scientists. This goal can be achieved through very diverse disconnections strategies, among which the direct alkynylation of CH bonds is particularly appealing due to the broad scope of substrates that can be employed. In this article, we focus on electrophilic alkynylation methodologies, which employ haloalkynes and hypervalent iodine reagents as acetylene donors. As a result of the length constrains, methodologies based on radical mechanisms and those under oxidative conditions, including cross‐dehydrogenative couplings, are out of scope. The existing protocols for electrophilic alkynylation are herein described and organized by their undirected or directed character. For the latter, different sections were considered according to the nature of the directing group.