Fully Delocalized Mixed-Valent Cu1.5 Cu1.5 Complex: Strong Cu-Cu interaction and Fast Electron Self-Exchange Rate Despite Large Structural Changes.
Angew Chem Int Ed Engl
; 62(10): e202215840, 2023 Mar 01.
Article
en En
| MEDLINE
| ID: mdl-36504436
ABSTRACT
A flexible macrocyclic ligand with two tridentate {CNC} compartments can host two Cu ions in reversibly interconvertible states, CuI CuI (1) and mixed-valent Cu1.5 Cu1.5 (2). They were characterized by XRD and multiple spectroscopic methods, including EPR, UV/Vis absorption and MCD, in combination with TD-DFT and CASSCF calculations. 2 features a short Cuâ
â
â
Cu distance (≈2.5â
Å; compared to ≈4.0â
Å in 1) and a very high delocalization energy of 13 000â
cm-1 , comparable to the mixed-valent state of the biological CuA site. Electron self-exchange between 1 and 2 is rapid despite large structural reorganization, and is proposed to proceed via a sequential mechanism involving an active conformer of 1, viz. 1'; the latter has been characterized by XRD. Such electron transfer (ET) process is reminiscent of the conformationally gated ET proposed for biological systems. This redox couple is a unique pair of flexible dicopper complexes, achieving fast electron self-exchange closely related to the function of the CuA site.
Texto completo:
1
Banco de datos:
MEDLINE
Idioma:
En
Año:
2023
Tipo del documento:
Article