Catalytic Asymmetric Synthesis of Diketopiperazines by Intramolecular Tsuji–Trost Allylation

We report the intramolecular Tsuji–Trost reaction of Ugi adducts to give spiro-diketopiperazines in high yield and with high enantioselectivity. This approach allows the catalytic asymmetric construction of a broad range of these medicinally important heterocycles under mild conditions, in two steps from cheap, commercially available starting materials.