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Diastereo- and Enantioselective Construction of Vicinal All-Carbon Quaternary Stereocenters via Iridium/Europium Bimetallic Catalysis. | LitMetric

The diastereo- and enantioselective construction of vicinal all-carbon quaternary stereocenters is a formidable task. We here report a synergistic bimetallic catalysis via a chiral N,N'-dioxide-europium (Eu) complex and a phosphoramidite-iridium (Ir) catalyst for the asymmetric allylation of oxindole derivatives by using challenging trisubstituted allylic esters. The allylated products bearing vicinal all-carbon quaternary stereocenters were obtained with good diastereoselectivities (up to 20 : 1 dr) and excellent enantioselectivities (up to 99 % ee). Control experiments showed that the complementary diastereomers of the products were not accessible by the change of the stereochemistry of the chiral N,N'-dioxide ligand.

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http://dx.doi.org/10.1002/anie.202208837DOI Listing

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