Enantioenrichments of α -Amino Acids With High-Intensity Excimer Laser

It has been found that the irradiation with highly intense circularly polarized light (CPL) from an XeF (351 nm) laser can induce the enantiodifferentiation of racemic methionine with reasonable enantiocontrol by switching the sense of the CPL. Also, a similar result was obtained for threonine and it was newly revealed that the enantioenrichment is largely affected by the chemical structure, especially the functional groups, of α-amino acids, to cause photodecomposition such as decarboxylation and deamination. Furthermore, it was shown for the first time that the irradiation of a proline (Pro)-valine (Val) mixture with the CPL induces their enantioselective decomposition simultaneously, suggesting the occurrence of intermolecular interaction between Pro and Val.