Directing‐Group‐mediated C−H‐Alkynylations

Abstract C−C triple bonds are amongst the most versatile functional groups in synthetic chemistry. Complementary to the Sonogashira coupling the direct metal‐catalyzed alkynylation of C−H bonds has emerged as a highly promising approach in recent years. To guarantee a high regioselectivity suitable directing groups (DGs) are necessary to guide the transition metal (TM) into the right place. In this Focus Review we present the current developments in DG‐mediated C(sp 2 )−H and C(sp 3 )−H modifications with terminal alkynes under oxidative conditions and with electrophilic alkynylation reagents. We will discuss further modifications of the alkyne, in particular subsequent cyclizations to carbo‐ and heterocycles and modifications of the DG in the presence of the alkyne.