Zinc amide catalyzed, regioselective allenylation and propargylation of ketones with allenyl boronate is reported. Tertiary allenyl and homopropargyl alcohols were obtained, respectively, in high selectivities, from the same starting materials, simply by changing the reaction conditions. The substrate scope was wide. Mechanistic studies suggest that the reactions are controlled under kinetic and thermodynamic conditions.
Identification of Modular Chiral Bisphosphines Effective for Cu(I)-Catalyzed Asymmetric Allylation and Propargylation of Ketones
Specifically, catalytic enantioselective propargylation was the first example, affording synthetically useful chiral building blocks that have not been easily accessed to date. In addition to the enantioselectivity, the high catalytic activity of the CuOAc-8 complex is noteworthy. Preliminary studies to elucidate the structure-catalyst activity relationship suggested that the high catalytic activity of