Organocatalytic Michael–Knoevenagel–Hetero-Diels–Alder Reactions: An Efficient Asymmetric One-Pot Strategy to Isochromene Pyrimidinedione Derivatives

Synthesis of isochromene pyrimidinedione derivatives having five stereocenters has been achieved by a one-pot Michael–Knoevenagel condensation–inverse-electron-demand hetero-Diels–Alder reaction of α, β-unsaturated aldehydes, olefinic nitroalkanes, and 1,3-dimethylbarbituric acid via a one-pot strategy with excellent diastereo- and enantioselectivities (up to 99% ee). The structures and absolute configurations of the products were confirmed by X-ray analysis.