Highly Enantioselective Imine Cinnamylation with a Remarkable Diastereochemical Switch

The first general method for the enantioselective cinnamylation of aldimines is reported. The method utilizes a simple chiral cinnamylsilane reagent and is characterized by experimental simplicity and extraordinarily high levels of enantioselectivity. Further, a remarkable and unprecedented diastereochemical reversal has been realized whereby either diastereomer may be accessed from the same trans-cinnamylsilane based upon a subtle change to the imine, thus obviating the usual requirement for both the trans- and cis-cinnamylsilanes.