Photostability and Dynamic Helical Behavior in Chiral Poly(phenylacetylene)s with a Preferred Screw-Sense.
Angew Chem Int Ed Engl
; 61(33): e202207623, 2022 08 15.
Article
in En
| MEDLINE
| ID: mdl-35731840
ABSTRACT
Helical polymers such as poly(phenylacetylene)s (PPAs) are interesting materials due to the possibility of tuning their helical scaffold (sense and elongation) once they have been prepared and by the presence of external stimuli. The main limitation in the application of PPAs is their poor photostability. These polymers degrade under visible light exposure through a photochemical electrocyclization process. In this work, it was demonstrated, through a selected example, how the photochemical degradation in PPAs is directly related to their dynamic helical behavior. Thus, while PPAs with dynamic helical structures show poor photostability under UV/Vis light exposure, poly-(R)-1, bearing an enantiopure sulfoxide group as pendant group and designed to have a quasi-static helical behavior, shows a large photostability due to the restricted conformational composition at the polyene backbone, needed to orient the conjugated double bonds prior to the photochemical electrocyclization process and the subsequent degradation of the material.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Polymers
/
Bone Screws
Language:
En
Journal:
Angew Chem Int Ed Engl
Year:
2022
Document type:
Article
Affiliation country:
Spain
Publication country:
ALEMANHA
/
ALEMANIA
/
DE
/
DEUSTCHLAND
/
GERMANY