MOP‐Type Binaphthyl Phosphite and Diamidophosphite Ligands and Their Application in Catalytic Asymmetric Transformations

Monodentate phosphite and diamidophosphite ligands have been developed based on O ‐methyl‐BINOL. These chiral ligands are easy to prepare from readily accessible phosphorylating reagents – ( S a or R a )‐2‐chlorodinaphtho[2,1‐ d :1′,2′‐ f ][1,3,2]dioxaphosphepine and ( 2R,5S )‐2‐chloro‐3‐phenyl‐1,3‐diaza‐2‐phosphabicyclo[3.3.0]octane. The new ligands have demonstrated excellent enantioselectivity in the palladium‐catalysed allylic substitution reactions of ( E )‐1,3‐diphenylallyl acetate with sodium p ‐toluenesulfinate (up to 99 % ee ), pyrrolidine (up to 97 % ee ), dipropylamine (up to 95 % ee ) and dimethyl malonate (up to 99 % ee ). In the palladium‐catalysed deracemization of ethyl ( E )‐1,3‐diphenylallyl carbonate, up to 96 % enantioselectivity has been achieved. The diamidophosphite ligands have exhibited very good enantioselectivity in the Rh‐catalysed asymmetric hydrogenation of dimethyl itaconate (up to 90 % ee ).