Chiral shift reagent


A chiral shift reagent is a reagent used in analytical chemistry for determining the optical purity of a sample. Some analytical techniques such as HPLC and NMR, in their most commons forms, cannot distinguish enantiomers within a sample, but can distinguish diastereomers. Therefore, converting a mixture of enantiomers to a corresponding mixture of diastereomers can allow analysis.
One method involves the reaction of a chiral derivatizing agent with a mixture of enantiomers to produce diastereomers via covalent attachment. One of the most common CDA is Mosher's acid.
Another method involves non-covalent interactions. NMR shift reagents such as EuFOD, Pirkle's alcohol, and TRISPHAT take advantage of the formation of diastereomeric complexes between the shift reagent and the analytical sample.