title: Structures of beta-amino ester enolates: new strategies using the method of continuous variation.
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.
authors.affiliation: Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
authors.forename: Lara R
authors.initials: LR
authors.lastname: Liou
authors.forename: Anne J
authors.initials: AJ
authors.lastname: McNeil
authors.forename: Gilman E S
authors.initials: GE
authors.lastname: Toombes
authors.forename: David B
authors.initials: DB
authors.lastname: Collum
mesh_terms: D002625:Chemistry, Organic / Q000379:methods*; D015195:Drug Design; D004952:Esters / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D015233:Models, Statistical; D012984:Software; D013237:Stereoisomerism
chemical_list: D004952:Esters; D008094:Lithium