Construction of Spirocyclic Oxindoles by Aminocatalysis Cascades

Significance

Aminocatalysis cascade reactions were employed for one-step construction of complex spirocyclic oxindoles 4 and 9. Starting from oxindoles 2 and α,β-unsaturated ketones 3 using primary amine catalyst 1 spirocyclic oxindoles 4 were obtained in moderate yields with high enan­tioselectivity. A complementary three-component reaction starting from oxindoles 6, aldehydes 7 and α,β-unsaturated aldehydes 8 was catalyzed by secondary amine catalyst 5. Spirocyclic oxindoles 9 were obtained in moderate yields with very high enantioselectivity.