A combined DFT and NMR investigation of the zinc organometallic intermediate proposed in the syn-selective tandem chain extension-aldol reaction of β-keto esters.

Academic Article


  • The tandem chain extension-aldol (TCA) reaction of β-keto esters provides an α-substituted γ-keto ester with an average syn:anti selectivity of 10:1. It is proposed that the reaction proceeds via a carbon-zinc bound organometallic intermediate potentially bearing mechanistic similarity to the Reformatsky reaction. Evidence, derived from control Reformatsky reactions and a study of the structure of the TCA intermediate utilizing DFT methods and NMR spectroscopy, suggests the γ-keto group of the TCA intermediate plays a significant role in diastereoselectivity observed in this reaction. Such coordination effects have design implications for future zinc mediated reactions.
  • Authors

  • Aiken, Karelle S
  • Eger, Wilhelm A
  • Williams, Craig M
  • Spencer, Carley M
  • Zercher, Charles
  • Status

    Publication Date

  • July 20, 2012
  • Published In


  • Aldehydes
  • Esters
  • Ketones
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Organometallic Compounds
  • Quantum Theory
  • Zinc
  • Digital Object Identifier (doi)

    Start Page

  • 5942
  • End Page

  • 5955
  • Volume

  • 77
  • Issue

  • 14