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Updated: Jan 12, 2026
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Published on: June 13, 2022
Merging Central and Axial Chirality in Cyclic(alkyl)(amino)carbenes: The Keystone for High Enantioselectivities in
Meng Liu1, Dylan Bouëtard1, Jakub Talcik1
1École Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, Univ Rennes, F-35000 Rennes, France.
Abstract:
A series of 38 chiral ruthenium complexes containing cyclic-(alkyl)-(amino)-carbene (CAAC) ligands with axial C-N chirality have been developed. By merging axial and central chirality, very high enantioselectivity (up to >99% ee) as well as good to high E-selectivity (up to 98%) were achieved in the asymmetric ring-opening cross-metathesis (AROCM) of various norbornene and cyclopropene derivatives. Furthermore, these catalysts are efficient in challenging asymmetric ring-closing ene-yne metathesis (ARCEYM), providing valuable enantioenriched building blocks (up to 90% ee). Mechanistic insights from density functional theory (DFT) calculations highlight the crucial role of axial chirality in CAAC ligands in governing both enantio- and diastereo-selectivity in the metathesis reaction.
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