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Published on: February 7, 2019
IBiox[(-)-menthyl]: a sterically demanding chiral NHC ligand
Sebastian Würtz1, Claudia Lohre, Roland Fröhlich
1Organisch-Chemisches Institut der Westfälischen Wilhelms-Universität Munster, Corrensstrasse 40, 48149 Münster, Germany.
Abstract:
An exceedingly sterically demanding, rigid, and chiral NHC ligand, IBiox[(-)-menthyl] (1), was prepared and structurally characterized. With a buried volume of approximately 50%, this ligand arguably represents one of the most sterically demanding monodentate ligands. The ability to use aryl chloride substrates in intramolecular palladium-catalyzed alpha-arylations reveals its unique reactivity. Moreover, C(2)-symmetric 1 allows the highly enantioselective formation of oxindoles with up to 99% ee.
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