Dynamic Kinetic Resolution of Axially Chiral Biaryls by Asymmetric Bromination

Significance

Axially chiral biaryl compounds are tremendously important for organic synthesis. Therefore, catalytic and asymmetric approaches toward this compound class are highly demandable. The authors demonstrate that the dynamic kinetic resolution of biaryl compound 2 can be realized by electrophilic aromatic substitution to afford the non-racemic biaryl 3. To explain the stereoselection of the catalysis, the authors suggest a catalyst-substrate complex in which several amide bonds and the tertiary amine in catalyst 1 participate via multiple hydrogen-bonding interactions.