Modular Functionalization of Allenes to Aminated Stereotriads

Nitrogen-containing stereotriads, compounds with three
adjacent
stereodefined carbons, are commonly found in biologically important
molecules. However, the preparation of molecules bearing these motifs
can be challenging. Herein, we describe a modular oxidation protocol
which converts a substituted allene to a triply functionalized amine
of the form C–X/C–N/C–Y. The key step employs
a Rh-catalyzed intramolecular conversion of the allene to a strained
bicyclic methylene aziridine. This reactive intermediate is further
elaborated to the target products, often in one reaction vessel and
with effective transfer of the axial chirality of the allene to point
chirality in the stereotriad.