title: The stereochemical course of intramolecular Michael reactions.
abstract: We present a general model for understanding the stereochemical course of intramolecular Michael reactions. We show that the addition of β-ketoester enolates to α,β-unsaturated esters and imides bearing adjacent stereocenters (X, Y = H, Me, OR) leads to high levels of asymmetric induction. Reinforcing and nonreinforcing stereochemical relationships are evaluated from the syn and anti reactant diastereomers. On the basis of synthetic, spectroscopic, and computational studies, we propose that the outcomes of these reactions can be rationalized by a dipole-minimized chair transition-state model.
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors.forename: Eugene E
authors.initials: EE
authors.lastname: Kwan
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Scheerer
authors.forename: David A
authors.initials: DA
authors.lastname: Evans
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D004952:Esters; D007094:Imides / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D002264:Carboxylic Acids; D004952:Esters; D007094:Imides