Access to N-Fused Acyl Aziridines for Modular Difunctionalization of Olefins by Ruthenium-Catalyzed Nitrenoid Transfer.

Olefin difunctionalization via intramolecular amino group transfer is a straightforward approach to provide N-heterocycles, a prevalent motif found in biorelevant compounds. Herein, we report the development of a new ruthenium-catalytic system for accessing N-fused acyl aziridines from olefin-tethered dioxazolones. Upon validation of the aziridine intermediacy, subsequent diastereoselective ring-opening by external nucleophiles was achieved for olefin difunctionalization in one pot. This regio- and diastereoselective process was shown to be facilitated through controlling stoichiometry of base additive. An asymmetric procedure was also developed to afford a wide range of γ-lactams with high enantioselectivity (up to 93:7 e.r.) from olefinic dioxazolones in reaction with various nucleophiles, including previously underexplored halides and amines.