Asymmetric conjugate addition of organometallic reagents to chiral α,β-unsaturated esters

Article abstract of DOI:10.1016/S0957-4166(00)82125-4

Asymmetric conjugate addition to α,β-unsaturated ester was studied using four kinds of cyclic diols (1c-4c) as chiral auxiliaries. Among the tested substrates, (R,R)-cyclohexane-1,2-diol derivatives (6a-c) and (1R,2S)-2-hydroxymethylcyclopentanol derivative (7a) showed high and reverse diastereoselectivity in conjugate addition by organocuprates (R₂CuLi) and/or Grignard reagents in the presence of copper iodide (RMgBr + CuI), respectively.