Efficient <i>Z</i>-Selective Olefin-Acrylamide Cross-Metathesis Enabled by Sterically Demanding Cyclometalated Ruthenium Catalysts
Yan Xu, Jonathan J. Wong, Adrian E. Samkian, Jeong Hoon Ko, Shuming Chen, K. N. Houk, Robert H. Grubbs
Abstract
The efficient Z-selective cross-metathesis between acrylamides and common terminal olefins has been developed by the use of novel cyclometalated ruthenium catalysts with bulky N-heterocyclic carbene (NHC) ligands. Superior reactivity and stereoselectivity are realized for the first time in this challenging transformation, allowing streamlined access to an important class of cis-Michael acceptors from readily available feedstocks. The kinetic preference for cross-metathesis is enabled by a pivalate anionic ligand, and the origin of this effect is elucidated by density functional theory calculations.
Topics & Concepts
ChemistryRutheniumCarbeneReactivity (psychology)MetathesisSteric effectsCatalysisLigand (biochemistry)StereoselectivityCombinatorial chemistryOlefin fiberOlefin metathesisAcrylamideOrganic chemistryPolymerizationCopolymerPolymerAlternative medicineBiochemistryReceptorMedicinePathologySynthetic Organic Chemistry MethodsN-Heterocyclic Carbenes in Organic and Inorganic ChemistryCatalytic Cross-Coupling Reactions