Structures of beta-amino ester enolates: new strategies using the method of continuous variation

J Am Chem Soc. 2008 Dec 24;130(51):17334-41. doi: 10.1021/ja8016957.

Abstract

The solution structures of four enolates derived from beta-amino esters are investigated using (6)Li NMR spectroscopy in conjunction with the method of continuous variation (method of Job). Ensembles of homo- and heteroaggregated enolates are generated by mixing enantiomers of a single enolate (R/S mixtures), opposite antipodes of two different enolates (R/S' mixtures), and the same antipodes of two different enolates (R/R' mixtures). The numbers of observable aggregates and their dependence on the mole fraction of the two enolates confirm the hexamer assignments. Inherent symmetries observable in the (6)Li NMR spectra show the stereochemistry of chelation about the hexagonal drum.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Chemistry, Organic / methods*
  • Drug Design
  • Esters / chemistry*
  • Lithium / chemistry
  • Magnetic Resonance Spectroscopy
  • Models, Chemical
  • Models, Molecular
  • Models, Statistical
  • Software
  • Stereoisomerism

Substances

  • Esters
  • Lithium