Development of Chiral Dinitrones as Modular Lewis Base Catalysts: Asymmetric Allylation of Aldehydes with Allyltrichlorosilanes

Chiral dinitrones were synthesized by condensation of a C2-symmetrical chiral dihydroxylamine with various aldehydes. The electronic and steric properties of the dinitrones can be modified by changing the aldehyde component. The activity of dinitrones as Lewis base catalysts was examined for the asymmetric allylation of aldehydes with allyltrichlorosilanes. Using DMPU as an additive in chloroform, the reaction proceeded at room temperature to afford allylated products in good yields and good enantioselectivities