Recent advances in radical transformations of internal alkynes.

Over the past years, impressive progress has been made on the development of the chemoselective and direct formation of carbon-carbon and carbon-heteroatom bonds involving internal alkynes under catalytic oxidative systems. These transformations heavily rely on the in situ generation of reactive radical intermediates that are initiated by oxidants, visible light photocatalysis, or electrocatalysis and so on. Numerous chemically and biomedically important building blocks have been synthesized, and will continue to be obtained by taking advantage of the radical transformation of internal alkynes in the following years. In this review, we highlight the recent progress in this rapidly growing area by presenting a series of catalytic oxidative reactions, mechanisms and applications which have appeared in the most recent literature.