Abstract: Asymmetric CC bond formation via the diastereoselective aza-Claisen rearrangement of N-allylketene N, O-acetal 1 is described. Diastereoselection noted for rearrangement 1-2 ranges from 84% to 96% and is a consequence of complete (2)-N, Oacetal olefin selectivity in 1, high C,-si-face selectivity in the rearrangement of 1 to 2, and the absence of C, epimerization in oxazoline 2. Experiments which establish the steric ...