Reductive desymmetrization of 2-alkyl-1,3-diketones catalyzed by optically active β-ketoiminato cobalt complexes

(Equation presented) The reductive desymmetrization of acyclic 1,3-diketones was achieved for the first time by catalytic borohydride reduction in the presence of optically active β-ketoiminato cobalt(II) complex catalysts. In this reaction, various 2-substituted-1,3-diaryl-1,3-propanediones were converted into the corresponding optically active 2-substituted-1,3-diaryl-3-hydroxypropanone in good-to-high yields with excellent diastereo-and enantioselectivities and high catalytic efficiencies.