Enantioselective [3+2] Cycloaddition of Donor‐Acceptor Aziridines and Imines to Construct 2,5‐trans‐Imidazolidines.

An enantioselective [3+2] cycloaddition of donor‐acceptor aziridines with N‐aryl protected imines was developed with a Ni(ClO4)2 ⋅ 6H2O/N,N′‐dioxide catalyst system, providing a broad range of chiral trans‐substituted imidazolidine compounds with good yields and excellent enantioselectivities (up to 99 % yield, up to 98 % ee). Control experiments indicated that the products could offer excellent diastereoselectivities with the control of chiral Ni(II)‐N,N′‐dioxide complex and the interaction of the substrates. The possible catalytic process was proposed to rationalize the stereocontrol. [ABSTRACT FROM AUTHOR]