Dynamic Kinetic Asymmetric Allylic Alkylations of Allenes

摘要

Efficient and atom economic methods for construction of chiral allenes are of significance due to the presence of this core structure in numerous natural and biologically important products,as well as synthetic intermediates for asymmetric synthesis of targets involving chirality transfer.Undoubtedly,the potential in this latter regard has been retarded by the limited accessibility of enantioenriched allenes.Typically,chiral allenes are derived from chiral propargylic alcohols.Only recently has asymmetric catalysis been employed for the construction of allenes.Several limited methods utilize the asymmetric addition of soft nucleophiles to vinyl-allyl Pd(II)intermediates accessed through both the oxidative addition of racemic 2,3-alkadienyl phosphates and prochiral vinyl bromides.