Abstract
Asymmetric 2,7-di-tert-butyl-10b,10c-dimethyl-2',3'-dimethyl-pyrazino[2,3-e]dihydropyrene (DMPZ-DHP) was prepared by the annulation of diamino dihydropyrene with 2,3-butanedione. Optical resolution was achieved using chiral high-performance liquid chromatography systems after the photoisomerization of DMPZ-DHP to DMPZ-metacyclophane-diene (MCPD), and its Kuhn's anisotropy factor (g = Delta epsilon/epsilon) was determined to be approximately 1.0 e(-3) at 550 nm. [S]- and [R]-DMPZ-DHP were irradiated with 550nm left and right circularly polarized light (CPL), and photoisomerization was found to proceed more rapidly upon irradiating the [S]-isomer with right-CPL than with left-CPL and upon irradiating the [R]-isomer with left-CPL than with right-CPL. This suggests that CPL can be detected and analyzed using asymmetric DMPZ-DHP. (C) 2022 Published by Elsevier Ltd.