An NMR method for assigning relative stereochemistry to beta-hydroxy ketones deriving from aldol reactions of methyl ketones.
We describe a simple 1H NMR analysis that permits the stereochemistry of beta-hydroxy ketones to be assigned by visual inspection of the ABX patterns for the alpha-methylene unit of the beta-hydroxy ketone in the 1H NMR spectra. This method has been verified by application to a wide range of beta-hydroxy ketones deriving from aldol reactions of chiral aldehydes with a variety of chiral and achiral methyl ketone enolates (see Tables 1 and 2). The stereochemistry of 54 of these compounds have been assigned by rigorous chemical methods.
Roush
William R
WR
Department of Chemistry, University of Michigan, Ann Arbor 48109, USA. roush@umich.edu
Bannister
Thomas D
TD
Wendt
Michael D
MD
VanNieuwenhze
Michael S
MS
Gustin
Darin J
DJ
Dilley
Garrett J
GJ
Lane
Gregory C
GC
Scheidt
Karl A
KA
Smith
William J
WJ
D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods*; D007659:Ketones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
D007659:Ketones; D008697:Methane