The absolute configuration of the stereogenic center at the β-position of a carboxylic acid can be determined via derivatization with chiral benzylic amines [PhCH(Me)NH2 or 1-NpCH(Me)NH2]. Acids of known configuration and with a variety of β-substituents were subjected to derivatization. Analysis of the signs of the chemical shift differences of substituent protons permits determination of the absolute configuration.
Bibliographical noteFunding Information:
This work was supported in part by the National Institutes of Health and an Egyptian Ministry of Education Fellowship (to A.-S.S.H.). We thank Drs. Maren Pink and Victor J. Young of the University of Minnesota X-ray Crystallographic Laboratory for determination of the structure of syn- vi .
- Carboxylic acids
- NMR spectroscopy