A direct, facile, and highly diastereo- and enantioselective dearomatization reaction of β-naphthol derivatives with aziridines has been developed for the first time. A newly designed Box-OH ligand was employed for an in situ generated magnesium catalyst and proved to be efficient. The corresponding dearomatization product was transformed into a polycyclic scaffold and polyhydroxylated compound. (1) H NMR studies revealed the activation mode of the dearomatization process of β-naphthols, and a clear positive nonlinear effect was observed in the reaction, and provides insight into the coordination environment around the Mg(II) center and the possible active species.

An asymmetric formal [3 + 2]-cycloaddition between meso-aziridines and C3-alkylindoles mediated by an in situ generated magnesium catalyst was developed for asymmetric construction of pyrroloindolines. A variety of pyrroloindolines could be obtained by employing commercial available ligands with the assistance of an easily prepared achiral ligand.

The asymmetric Michael reaction between 5H-oxazol-4-ones and α,β-unsaturated acyl imidazoles is reported. A novel 2-benzo[b]thiophenyl-modified chiral ProPhenol species is synthesized and used as a ligand, leading to good enantioselectivities in this asymmetric conjugate addition reaction. Furthermore, the introduction of phenol additives as achiral co-ligands is found to improve the reaction's chemical yields, diastereoselectivities, and enantioselectivities.

A magnesium-catalyzed asymmetric ring-opening reaction of aziridine with indole has been realized by employing commercially available chiral ligands. Both of the enantiomers of the ring-opening product could be obtained with good yields and a high level of enantioselectivity. The corresponding ring-opening product could be further transformed to various types of enantioenriched C3 -halogenated-pyrroloindolines.

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