The Ir-Catalyzed Asymmetric Hydrogenation of α-Halogenated Ketones Utilizing Cinchona-Alkaloid-Derived NNP Ligand to Produce (<i>R</i>)- and (<i>S</i>)-Halohydrins
Qian Chen, Hao Sun, Lin Li, Jie Tian, Qian Xu, Nana Ma, Li Li, Lin Zhang, Chun Li
Abstract
The asymmetric hydrogenation of α-halogenated ketones with iridium catalyst was developed, utilizing easily accessed cinchona-alkaloid-based NNP ligands. Various α-chloroacetophenones, heterocyclic thienyl and furanyl substrates, and even bromoketones were completely converted to the desired chiral halohydrins by this protocol. Both (R)- and (S)-chiral halohydrins can be prepared by changing the configurations of the chiral ligand NNP with up to 99.6% ee (enantiomeric excess) and 98.8% ee, respectively. Also, a gram-scale experiment was carried out efficiently.
Topics & Concepts
ChemistryCinchonaIridiumAsymmetric hydrogenationEnantiomerCatalysisLigand (biochemistry)Enantiomeric excessEnantioselective synthesisAlkaloidChiral ligandOrganic chemistryCombinatorial chemistryBiochemistryReceptorAsymmetric Hydrogenation and CatalysisSurface Chemistry and CatalysisCatalysis for Biomass Conversion