Dendritic polyphenylene framework as a light-harvesting shell for highly emissive [2.2]Paracyclophane core

• Published in: Polymer (Guilford) 2021-11, Vol.234, p.124227, Article 124227
• Main Authors: Krasnova, Irina Yu, Antonov, Dmitrii Yu, Shapovalov, Alexey V., Shifrina, Zinaida B.
• Format: Article
• Language: English
• Subjects: [2.2]paracyclophane; dendrimer; Dendrimers; Diels-Alder reactions; Energy transfer; light-harvesting shell; Optical properties; Photoluminescence; Photons; Ultraviolet radiation
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2021.124227

New polyphenylene type dendrimers of two generations were developed through attaching the aromatic dendron units to the highly emissive conjugated 4,7,12,15-tetra(phenylethynyl)[2.2]paracyclophane core via the Diels-Alder reaction. The polyphenylene moieties in dendrimers efficiently absorbed the UV light, followed by the energy transfer to the [2.2]paracyclophane core, resulting in photoluminescence with high quantum yields from the core unit and demonstrating efficient intramolecular energy transfer. The detailed analysis of optical properties of polyphenylene dendrimers with the [2.2]paracyclophane core was carried out using parent model compounds that resemble the constituents of respective dendrimers. The success of this study became possible to a certain extent due to an improvement of the synthetic procedure for 4,7,12,15-tetraethynyl substituted [2.2]paracyclophane derivatives allowing for high yields of target products. [Display omitted] •New cross-conjugated dendrimers based on [2.2]-paracyclophane were synthesized.•High quantum yield of photoluminescence of dendrimers was detected.•Effective energy transfer from polyphenylene shell to [2.2]-paracyclophane core was established in dendrimers.