1,7-Asymmetric Induction in a Nitrogen Ring Expansion Process Facilitated by in Situ Tethering

Abstract

[formula: see text] There are only a few methods for the asymmetric ring expansion of prochiral ketones. Symmetrically substituted cyclohexanones can be converted to the corresponding ring-expanded caprolactam with excellent 1,7-diastereoselectivity (> or = 93% ds) and yields (> or = 86%), using a chiral hydroxy azide-mediated Schmidt reaction.