Direct catalytic asymmetric aldol additions of methyl ynones. Spontaneous reversal in the sense of enantioinduction

J Am Chem Soc. 2004 Mar 10;126(9):2660-1. doi: 10.1021/ja038666r.


In this Communication, we report the direct, catalytic, asymmetric aldol addition of methyl ynones using our dinuclear zinc catalyst. A spontaneous reversal in the sense of enantioinduction was observed for these reactions; formation of the (S)-enantiomer is favored in the early stages (69% ee after 5 min), whereas the (R)-enantiomer is isolated as the major product after prolonged reaction times (97% ee after 22 h). It could be shown that this reversal in enantioselectivity is due to formation of a new catalytic species which incorporates the aldol product.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alcohols / chemical synthesis*
  • Aldehydes / chemistry*
  • Alkynes / chemical synthesis
  • Alkynes / chemistry*
  • Catalysis
  • Ketones / chemical synthesis
  • Ketones / chemistry*
  • Stereoisomerism


  • Alcohols
  • Aldehydes
  • Alkynes
  • Ketones