Structure and asymmetric Diels-Alder reactions of optically active allene-1,3-dicarboxylates

The structure and asymmetric Diels-Alder reaction of allene-1,3-dicarboxylates with cyclopentadiene were determined towards pi-face selective reactions due to the axial asymmetry of the allene moiety. The reactions afforded endo adducts formed by the easy access of the diene and the dienophile. The favorable approach is indeed provided by the axial asymmetry of the allene moiety and the secondary optical interaction.