Synthesis of Diversely Substituted Imidazolidines via [3+2] Cycloaddition of 1,3,5‐Triazinanes with Donor‐acceptor Aziridines and Their Anti‐tumor Activity

A Y(OTf)3‐catalyzed [3+2] cycloaddition of 1,3,5‐triazinanes with donor‐acceptor aziridines has been developed, accessing diversely substituted imidazolidines high efficiency. Mechanistic investigations support the formation of imidazolidines through an SN1‐like pathway. Furthermore, these imidazolidines exhibit promising anti‐tumor activity against a series of human cancer cell lines.