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 A(3)-coupling, has been established as a convenient and general approach towards propargylamines. Furthermore, the A(3)-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 A(3)-coupling as well as different tandem reactions involving A(3)-coupling have been developed. This tutorial review aims to highlight the current achievements in the field of A(3)-couplings and related transformations.