Carregant...
Fitxers
Tipus de document
ArticleVersió
Versió publicadaData de publicació
Tots els drets reservats
Si us plau utilitzeu sempre aquest identificador per citar o enllaçar aquest document: https://hdl.handle.net/2445/169288
Photochemical, Photophysical and Electrochemical Properties of a Photoisomerizable Cyclophane and its [2]Catenates with Aromatic Crown Ethers
Títol de la revista
Director/Tutor
ISSN de la revista
Títol del volum
Recurs relacionat
Resum
The photochemical, photophysical, and electrochemical behaviour of t-1,2-bis(1-benzy1-4- pyridinium)ethylene (t-DBBPE2+) (used as model compound), a cyclophane made of two t-1,2-bis(4-pyridin-ium)ethylene (BPE) units (141, and its catenanes (1B134+,1BN4+, and INN') with aromatic crown ethers containing two p-dimethoxybenzene units (BB), one p-dimethoxybenzene and one 1,5-dimethoxynaphthalene unit (BN), and two 1,5-dimethoxynaphthalene units (NN) have been investigated in acetonitrile solution. For both t-DBBPE' and 14+, fluorescence and direct trans-*cis photoisomerization are prevented by the presence of an intramolecular charge-transfer (CT) excited state close to or below the lire level, but the triplet-sensitized photoisomerization takes place with high quantum yield. In the 1BB4*, 1BN4', and 1NN4' catenanes, also the triplet sensitized photoisomerization is quenched by the presence of lower lying inter-component CT levels. The intercomponent CT interaction present in the catenanes affects the reduction potentials of the t-DBBPE2+ units of 14+. Such an interaction, which plays the role of a brake against the free rotation of the two rings of catenanes, is released upon reduction of the 14+ cyclophane.
Matèries
Matèries (anglès)
Citació
Citació
BALLARDINI, Roberto, BALZANI, Vincenzo, CREDI, A. (alberto), GANDOLFI, Maria teresa, PRODI, Luca, VENTURI, Margherita, PÉREZ GARCÍA, M. lluïsa (maria lluïsa), STODDART, J. frasser. Photochemical, Photophysical and Electrochemical Properties of a Photoisomerizable Cyclophane and its [2]Catenates with Aromatic Crown Ethers. _Gazzetta Chimica Italiana_. 1995. Vol. 125, núm. 353-359. [consulta: 24 de gener de 2026]. ISSN: 0016-5603. [Disponible a: https://hdl.handle.net/2445/169288]