The first stereodivergent umpolung 1,5-conjugate addition reaction via synergistic
Pd/Cu catalysts is reported. By dictating the absolute configuration of each chiral
ligand ligated to corresponding metals, all four stereoisomers of the products are
easily achieved. A series of amino acid moieties are introduced to the γ-position
of the conjugated esters in high yields with excellent diastereoselectivities and
enantioselectivities. The downstream transformations highlight the synthetic value
of the method.
Key words
stereodivergent - 1,5-conjugate addition - palladium - copper - synergistic catalysis