Helicity-Dependent Regiodifferentiation in the Excited-State Quenching and Chiroptical Properties of Inward/Outward Helical Coumarins.
Chemistry
; 23(59): 14797-14805, 2017 Oct 20.
Article
em En
| MEDLINE
| ID: mdl-28792106
ABSTRACT
Influence of helicity on the excited-state as well as chiroptical properties of two sets of regiohelical coumarins that are differentiated by "inward" and "outward" disposition of the pyran-2-one ring has been investigated. A subtle difference in the helicities manifests in divergent excited-state properties and significant differences in the dipole moments. The latter permit heretofore unprecedented regiodifferentiation in the O-Hâ
â
â
O hydrogen-bond assisted electron-transfer quenching by phenols. Furthermore, the enantiopure hexahelical coumarins exhibit strong Cotton effects and lend themselves to a very high differentiation in the specific rotations and anisotropic dissymmetry factors. The specific rotation observed for 6-in turns out being the highest of the values reported for all hexahelicenes reported so far.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cumarínicos
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article