Inherently Chiral Seven- and Eight-Membered Rings: Enantioselective Synthesis and Applications.

Compared to smaller or larger rings, seven- and eight-membered carbo- and heterocycles are typically nonplanar and exhibit greater conformational rigidity. This property alone can impart chirality to certain 7- or 8-membered ring systems. Herein, we summarize recent achievements in the enantioselective synthesis of this class of inherently chiral medium rings, including both ring construction and ring modification, as well as the applications of chiral ligands and catalysts derived from these rigid cyclic scaffolds in asymmetric catalysis.