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Updated: Aug 29, 2025
Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Rhodium(II)-Catalyzed Enantioselective Intermolecular Aziridination of Alkenes
Vincent Boquet1, Ali Nasrallah1, Alejandro L Dana2,3
1Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198 Gif-sur-Yvette, France.
Abstract:
C4-Symmetrical dirhodium(II) tetracarboxylates are highly efficient catalysts for the asymmetric intermolecular aziridination of substituted alkenes with sulfamates. The reaction proceeds with high levels of efficiency and chemoselectivity to afford aziridines with excellent yields of up to 95% and enantiomeric excesses of up to 99%. The scope of the alkene aziridination includes mono-, di-, and trisubstituted olefins as well as the late-stage functionalization of complex substrates. The reaction can be performed on a gram-scale with a catalyst loading of 0.1 mol %. Our DFT study led us to propose a two-spin-state mechanism, involving a triplet Rh-nitrene species as key intermediate to drive the stereocontrolled approach and activation of the substrate.
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