Asymmetric construction of quaternary centers by enantioselective allylation: Application to the synthesis of the serotonin antagonist LY426965

[GRAPHICS] Catalytic enantioselective allylation with a chiral bisphosphoramide was applied to the synthesis of LY426965, a serotonin antagonist. The key step, addition of a 3,3-disubstituted allyltrichlorosilane to benzaldehyde, provided the adduct containing a stereogenic quaternary center with excellent diastereoselectivity and enantioselectivity.