Simple and Fast Synthesis of New Axially Chiral Bipyridine N,N′‐Dioxides for Highly Enantioselective Allylation of Aldehydes

Abstract magnified image Unsymmetrically 3,3′‐substituted axially chiral bis(tetrahydroisoquinoline) N,N′‐ dioxides can be prepared in just three steps. They exhibit unique catalytic activity (turnover frequency, enantioselectivity, substrate scope) in the asymmetric allylation of aromatic aldehydes (up to 96% ee ). The product of the enantioselective allylation of benzaldehyde served as a building block for the preparation of an intermediate useful in the enantioselective synthesis of diospongines.