Highly Regio‐ and Enantioselective Cu/Pd Co‐Catalyzed Allylic Alkylation of α‐pyridyl‐α‐fluoroesters: Construction of Quaternary C−F Stereocenters

An efficient synergistic Pd/Cu catalyst system for the highly regioselective asymmetric allylation of α-pyridyl-α-fluoroesters constructed straight-chain allyl products containing C−F quaternary stereocenter. A series of aryl- and aliphatic-substituted straight-chain allyl products were obtained in high yields, excellent enantioselectivities and E/Z-selectivities (up to 98% yield, 98 : 2 er, and >20 : 1 E/Z).

Abstract

New methods for preparation of chiral alkyl fluorides have been studied intensively in recent years due to the favorable physicochemical and biological properties of those structures. Herein, we describe the regio- and enantioselective allylic alkylation of α-pyridyl-α-fluoroesters with allyl acetates promoted by Cu/Pd synergistic catalysis, constructing the carbon- fluorine quaternary stereocenters. In this co-catalytic system, palladium catalyst mainly constructed the C−C bond, while chiral copper catalyst controlled the enantioselectivity. A series of aryl- and aliphatic-substituted allyl acetates are applied, giving the corresponding products in high yield, excellent enantioselectivity, and E/Z (up to 98% yield, 98 : 2 er, E/Z>20 : 1).

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