A New Approach to Axially Chiral Bipyridine N,N′‐Dioxides Bearing Aromatic Substituents and their Use for Catalytic Asymmetric Allylation of Aldehydes with Allyl(trichloro)silane

Palladium‐catalyzed cross‐coupling of bipyridine N,N′‐dioxide 6,6′‐dichloride (Rnap,Rpyr)‐1 with the aryl Grignard reagents opened a new approach to axially chiral bipyridine N,N′‐dioxides (R)‐2 bearing a variety of aryl groups at the 6 and 6′ positions. One of the N,N′‐dioxides (R)‐2d which is substituted with 3,5‐dimethyl‐4‐methoxy groups was found to be highly catalytically active and enantioselective for the asymmetric allylation of aldehydes with allyl(trichloro)silane. The allylation took place with 0.01–0.1 mol % of (R)‐2d giving homoallyl alcohols of up to 94% ee.