Rh(I)/Bisoxazolinephosphine-Catalyzed Regio- and Enantioselective Allylic Substitutions
Wenbin Xu, Samir Ghorai, Wenyu Huang, Changkun Li
Abstract
Rhodium(I)/bisoxazolinephosphine combination has been developed as a general catalyst to achieve the dynamic kinetic asymmetric allylation of a variety of nitrogen, carbon, oxygen, and sulfur pronucleophiles from branched racemic allylic carbonates. Exclusive branch-selectivity and up to 99% enantiomeric excess could be obtained under neutral conditions. Linear allylic substrates (both Z and E) could be converted to the same chiral branched products with excellent regio- and enantioselectivities as well. Chiral π-allyl-Rh(III)/NPN intermediate was isolated and characterized to understand the origin of the high selectivities.
Topics & Concepts
Allylic rearrangementEnantioselective synthesisCatalysisChemistryRhodiumKinetic resolutionEnantiomerSelectivitySulfurEnantiomeric excessOrganic chemistryMedicinal chemistryStereochemistryAsymmetric Hydrogenation and CatalysisAsymmetric Synthesis and CatalysisSynthetic Organic Chemistry Methods