In this work six kinds of tartrate diesters were prepared from D(-)

L(+) or DL-tartaric acid respectively

and their structure were verified by IR and NMR. The extraction behavior of optical compounds

D(-) ephedrine and L(+) pseudoephedrine

was investigated at room temperature using prepared tartrate diester as extracting agent and n -heptane as diluent. The ratio of tartrate diester and n -heptane is 1∶1. Distribution coefficients

obtained from experiment data by material balance

show that there is a chiral recognition: L(+) tartrate diesters favour extraction of L(+) pseudoephedrine

while D(-) tartrate diesters favour extraction of D(-) ephedrine. The extraction behavior of the mixture of the above optical active epimerides

was also investigated under the same experimental conditions. The experiment data with HPLC also showed the same conclusion. Meanwhile

a blank experiment was carried out and the result showed that there was no evident effect on extraction distribution coefficients when extraction process occurred in the presence of n -heptane. The relationship between the structure of extracting agent and optical activity of the epimerides was also discussed.