Benzo‐Tetrathiafulvalene‐ (BTTF‐) Annulated Expanded Porphyrins: Potential Next‐Generation Multielectron Reservoirs. Issue 13 (28th January 2021)

• Record Type: Journal Article
• Authors: Jana, Atanu; Ishida, Masatoshi; Furuta, Hiroyuki
• Is Part Of: Chemistry. Volume 27:Issue 13(2021)
• Page Start: 4466
• Page End: 4472
• Publication Date: 2021-01-28
• Subjects: density functional calculations -- electrochemistry -- expanded porphyrins -- intramolecular charge transfer -- tetrathiafulvalene; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202005021
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Two sterically crowded benzo‐tetrathiafulvalene (BTTF)‐annulated expanded porphyrins (BTTF7‐F and BTTF8 ) are synthesized. Detailed photophysical investigations reveal their intrinsic intramolecular charge transfer (CT) character, originated from partial electron transfer from electron‐rich TTF units to the relatively electron‐deficient macrocyclic core. This finding stands in contrast to what was observed in the previously reported Figure‐of‐eight conformer of BTTF‐annulated [28]hexaphyrin (BTTF6 ), in which a typical π–π* electronic transition from HOMO to LUMO was observed. However, core expansion in BTTF7‐F and BTTF8 makes the oligopyrrole macrocyclic cores relatively more electron‐deficient, facilitating the effective intramolecular CT process. Comparative electrochemical investigations reveal that the current generated at the oxidative region is directly proportional to the number of TTF units attached to the macrocyclic core. This work demonstrates the control of the intramolecular CT process through incremental addition of TTF units to the macrocyclic core. Facile multielectron electrochemical oxidations of these expanded porphyrins suggest that they behave like potential multielectron reservoirs. Abstract : Expanded porphyrins : Two new benzo‐TTF‐annulated expanded porphyrins show effective intramolecular charge transfer (CT) transitions from TTF moieties to the macrocyclic core. Electrochemical investigations reveal that these electron‐rich materials could be used as efficient electron reservoirs for material applications.