1‐Haloalkynes: Privileged Substrates for Gold Catalysis

Alkynes have been the preferred substrates since the early development of gold catalysis at the dawn of this century. Amongst them, 1‐haloalkynes have gained increased interest in recent years due to the versatility offered by these bifunctional entities as well as the identification of unique reaction modes in this already mature research field. Herein, the seminal contributions that resulted in the observed growth in recent years and the most recent developments will be discussed. The ability of 1‐haloalkynes to undergo halogen migrations under gold catalysis has unveiled unprecedented reaction modes. C−H insertions, alkyne dimerization and olefin haloalkynylation are amongst the most characteristic reactivities of these multifaceted reagents. The presence of a C−Br bond in the products ready for further functionalization results in an increased added value.