Chiral Imidazoline Ligands and Their Applications in Metal-Catalyzed Asymmetric Synthesis†

As a structural analog of oxazoline, imidazoline (4,5-dihydroimidazole) has received much attention in the rational design of chiral ligands. The additional N-substituent provides broader space for fine-tuning of electronic and steric effects, and it offers a good handle for immobilizing onto solid supports. In the past decades, imidazoline ring has emerged as a powerful candidate for the design of chiral nitrogen-containing ligands, as well as a significant alternative for oxazoline ring. Various chiral imidazoline ligands have been designed and utilized in asymmetric organic reactions. These new catalysts can not only be applied in classical reactions, but also be employed to develop new organic reactions with high enantioselectivities. This review provides an overview of chiral imidazoline ligands. Their applications in asymmetric synthesis are also summarized.

Automated summary

Imidazoline, as a structural analog of oxazoline, has gained significant attention in the rational design of chiral ligands due to its additional N-substituent allowing for fine-tuning of electronic and steric effects. Various chiral imidazoline ligands have been designed and employed in asymmetric organic reactions, expanding the applications of chiral synthesis.