Determining Enantiomeric Excess Utilizing Ratiometric Measurements of a Deuterium Labeled Malonate by 1H NMR Spectroscopy

Enantiomeric excess quantification is important in the synthesis of many small molecules. Esterase enzymes such as porcine liver esterase are known for their ability to generate high enantioselectivity. Many methods have been developed in order to measure the enantiomeric excess of a chiral mixture. Herein we report a new method of direct quantification by 1H NMR spectroscopy of an enantiomeric mixture using ratiometric measurements of an isotope labelled probe. Our method has been demonstrated to be comparable to that of HPLC and yield quantitative results with ease.