Synthesis and photochromic circular dichroism of 2,7-di-tert-butyl-10b,10c-dimethyl-pyrazino[2,3-e]dihydropyrene

Abstract

2,7-Di-tert-butyl-10b,10c-dimethyl-pyrazino[2,3-e]dihydropyrene was prepared and its photochromic properties were studied. The open form of the molecule was separated into its constituent enantiomers by chiral HPLC. The absolute structures of the enantiomers were determined by using spectra predicted with time-dependent density functional theory. Photoswitchable circular dichroism properties of 2,7-di-tert-butyl-10b,10c-dimethyl-pyrazino[2,3-e]dihydropyrene were observed, suggesting its potential for application in molecular devices.

Chirality and Circular Polarized Properties of Photochromic Polyaromatic Molecules

“…Although the methyl protons of toluene were detected at 2.31 ppm, internal methyl group of DHP 16 were observed at −1.03 ppm in toluene-d 8 . The chemical shifts of internal methyl protons of other DHPs 9, 15, and 17 were observed at −3.61, [20], −0.14 [15], and − 1.53 pp [14], respectively. The degree of upshielding effects was different due to the heterocycle unit and functional groups of DHPs.…”

“…In this chapter, we will describe about our recent topics about the syntheses, photochromism, and circular polarized properties of asymmetrical-functionalized DHPs [14][15][16][17].…”