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Abstract: Cu-catalyzed enantioselective 1,4-conjugate addition of β,γ-unsaturated α-keto ester compound was carried out to afford chiral γ-substituted γ-aryl α-keto ester, which could be conveniently converted to the potential skeleton of new Pril drugs. Up to 81% ee and 99% yield were afforded for the 1,4-conjugate addition using D 2-symmetric biphenyl phosphoramidite ligand. [Copyright &y& Elsevier]

Abstract: A novel class of atropos dibridged biphenyl phosphoramidites bearing a D 2-symmetric biphenyl backbone was prepared and applied as chiral ligands in the copper-catalyzed allylic alkylation with Grignard reagent. The alkylation products were obtained in quantitative yields with high regioselectivities up to 94:6 of SN2′/SN2 ratio and enantiomeric excesses up to 91.1% for SN2′ products. The unique D 2-symmetric backbone ligands have the advantages of easy preparation and sufficient reusability of their key intermediates from the undesired isomers. [Copyright &y& Elsevier]