Synthesis of Planar‐Chiral [2.2]Paracyclophane‐Based Oxazole‐Pyrimidine Ligands and Application in Nickel‐Catalyzed 1,2‐Reduction of α,β‐Unsaturated Ketones

Comprehensive Summary The planar‐chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric catalysis. Among them, chiral [2.2]paracycyclophane has emerged as a privileged type of planar‐chiral framework and has been utilized as an important toolbox due to their structural stability. Herein, we design and synthesize [2.2]paracyclophane‐derived oxazole‐pyrimidine ligands (abberviated as PYMCOX). These N , N ‐ligands with stable properties, rigid structure and large steric hindrance performed successfully in nickel‐catalyzed asymmetric 1,2‐reduction of α,β‐unsaturated ketones, affording the chiral allylic alcohols with up to 99% yield and 99% ee. Meanwhile, this reduction reaction could be conducted on gram‐scale without loss of activity and enantioselectivity, and the chiral ligand could be conveniently recovered with high yield.