AIMTo discuss the relationship between the three-point interaction principle in the stereoselective separation of chromatography and applying this principle to survey the infrared spectrometry of racemate.

METHODSIn proving the applicability of the three-point interaction principal in IR spectrometry, a special case was found that phenylglycine did not obtain enantioselective separation on the chiral column but its IR spectrometry still obey this principle and explained such special case by experiment.

RESULTSAfter an equal quantity of solid crystal of d-phenylglycine and l-phenylglycine were mixed and ground for several minutes, they transformed to racemic compound. X-powder diffraction also confirmed this fact.

CONCLUSIONThe three-point principle was relatively reliable when it was used in the enantioselective chromatography separation and the IR spectrometric analysis. The reason of the fact that phenylglycine was not separated by chiral column can be explained by the fact that the acting force between the three polarity groups in the enantiomers is so strong that they can not form the instantaneous diastereoisomer with the chiral column, it was agreeable with the phenomenon that racemic mixture easily became racemic compound only by simply grinding the mixture in IR spectrometric experiment.