Modular Synthesis of Chiral Trisubstituted 1,2‐Allenyl Ketones Enabled by Organophosphine Dual‐Reagent Catalysis

Comprehensive Summary A catalytic asymmetric conjugate addition of malonic esters to yne‐enones was successfully achieved via coperative catalysis of chiral biamide‐phosphine and methyl acrylate, which afforded the corresponding chiral trisubstituted 1,2‐allenyl ketones containing contigous axial and carbon center chirality with excellent enantioselectivity (up to 99% ee) and good diastereoselectivity (up to 93 : 7 dr). It is meaningful to note that the addition of an inorganic base (K 2 CO 3 ) did not cause the background racemic reaction but could enhance the reactivity as a co‐catalyst.