The redox-A(3) reaction

This highlight details the recent emergence of a new type of A(3) reaction (three-component condensation of an amine, an aldehyde and an alkyne). In contrast to the classic A(3) coupling process, the redox-A(3) reaction incorporates an iminium isomerization step and leads to amine alpha-alkynylation. The overall transformation is redox-neutral by virtue of a combined reductive N-alkylation/oxidative C-H bond functionalization.