Diels–Alder Chemistry of Ketenimines: Toward Highly Reactive Aza-Dienophiles

Abstract The development of new cycloaddition partners remains central to advancing our understanding of molecular structure and pericyclic reactivity, while also enabling increasingly convergent synthetic strategies. In this context, the development of heteroatom-containing cycloaddition components is especially compelling, as such platforms enable streamlined access to heterocyclic frameworks that are prevalent throughout the pharmaceutical landscape. This Perspective provides an overview of ketenimine Diels–Alder chemistry and describes how this reactivity, together with the related chemistry of ketenes, has inspired our recent efforts to establish ketenimines as highly reactive aza-dienophiles.