A walk around the A³-coupling

In recent years, the transition-metal catalyzed three-component coupling of an aldehyde, an alkyne and an amine, commonly called A³-coupling, has been established as a convenient and general approach towards propargylamines. Furthermore, the A³-coupling has found a broad application as a key step in the construction of various nitrogen-containing heterocycles, biologically active compounds and natural products. Several interesting modifications of the A³-coupling as well as different tandem reactions involving A³-coupling have been developed. This tutorial review aims to highlight the current achievements in the field of A³-couplings and related transformations.