Fig. 5. Scheme used to determine pro-chiral faces during MD. A unit vector, Vbond (orange) represents the reference orientation of the nascent C–C bond going from enamine (ENP) to the aldehyde (PHA). The faces are distinguished in terms of unit vectors, V1 and V2 for each species, whose cross product V1 × V2 = Vface (purple) determines the orientation of a prochiral face. The dot product Vface × Vbond results in a positive or negative value and assigns a Re face or Si face to a molecule.
