Photoinduced electron transfer in host-guest interactions of a viologen derivative with a didansyl-pillar[5]arene. (June 2022)

• Record Type: Journal Article
• Authors: Pisagatti, I.; Crisafulli, D.; Pappalardo, A.; Trusso Sfrazzetto, G.; Notti, A.; Nastasi, F.; Parisi, M.F.; Micali, N.; Gattuso, G.; Villari, V.
• Is Part Of: Materials today chemistry. Volume 24(2022)
• Publication Date: 2022-06
• Subjects: Pillararenes -- Viologen -- Dansyl -- Photoinduced electron transfer -- DOSY NMR -- Host-guest complexation; Chemistry -- Periodicals; Materials -- Research -- Periodicals; Materials science -- Periodicals; Chemistry; Materials -- Research; Electronic journals; Periodicals; 660.282
• DOI: 10.1016/j.mtchem.2022.100841
• Languages: English
• ISSNs: 2468-5194

Abstract

Abstract: With the goal of understanding the electron transfer mechanism of fluorophore-functionalized pillararenes, a pillar[5]arene bearing two dansyl fluorophore moieties at the opposite rims of its cavity has been synthesized, and the behavior of such a new host molecule has been thoroughly investigated in the presence of an N, N′ -di-(6-bromohexyl)-viologen derivative. 1 H NMR, NOESY and DOSY experiments demonstrated that the pillar[5]arene recognizes the viologen derivative, forming a 1:1 host-guest complex by including one of the two bromoalkyl chains within its π-rich cavity. Photophysical and electrochemical studies revealed that, upon guest addition to the host, the fluorescence intensity of the complex is progressively quenched by a photoinduced electron transfer process (PET) from one of the dansyl groups of the host to the viologen moiety of the guest. Graphical abstract: Image 1 Highlights: A pillar[5]arene bearing two dansyl fluorophore moieties has been synthesized. The pillararene forms a 1:1 complex with N, N′ -di (6-bromohexyl)-bipyridinium. Fluorescence of the complex is progressively quenched by a dansyl-to-viologen PET.