Construction of Helical Structures with Multiple Fused Anthracenes: Structures and Properties of Long Expanded Helicenes.
Chemistry
; 27(14): 4548-4552, 2021 Mar 08.
Article
em En
| MEDLINE
| ID: mdl-33205503
ABSTRACT
Polycyclic aromatic compounds consisting of four or five fused anthracene units were synthesized by PtCl2 -catalyzed cycloisomerization as novel long expanded helicenes. These compounds have helical structures with significant stacking of the terminal anthracene moieties at 0.33â
nm interlayer distance. In the UV-vis and fluorescence spectra, the absorption and emission bands were red-shifted as the number of fused anthracene units was increased. The characteristic broad and long-lived emission bands of the long analogues are explained by the excimer-like stabilization of the excited state. These photophysical data as well as their cyclic voltammetric data are discussed on the basis of the π-conjugation and interlayer πâ
â
â
π interactions in the molecular structures and the molecular orbitals. The barrier and mechanism of helical inversion are also reported.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Chemistry
Assunto da revista:
QUIMICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Japão