Copper Guanidinoquinoline Complexes as Entatic State Models of Electron-Transfer Proteins.
Chemistry
; 23(62): 15738-15745, 2017 Nov 07.
Article
en En
| MEDLINE
| ID: mdl-28850743
ABSTRACT
The electron-transfer abilities of the copper guanidinoquinoline (GUAqu) complexes [Cu(TMGqu)2 ]+/2+ and [Cu(DMEGqu)2 ]+/2+ (TMGqu=tetramethylguanidinoquinoline, DMEGqu=dimethylethylguanidinoquinoline) were examined in different solvents. The determination of the electron self-exchange rate based on the Marcus theory reveals the highest electron-transfer rate of copper complexes with pure N-donor ligands (k11 =1.2×104 â
s-1 m-1 in propionitrile). This is supported by an examination of the reorganisation energy of the complexes by using Eyring theory and DFT calculations. The low reorganisation energies in nitrile solvents correspond with the high electron-transfer rates of the complexes. Therefore, the [Cu(GUAqu)2 ]+/2+ complexes act as good entatic states model of copper enzymes. The structural influence of the complexes on the kinetic parameters shows that the TMGqu system possesses a higher electron-transfer rate than DMEGqu. Supporting DFT calculations give a closer insight into the kinetics and thermodynamics (Nelsen's four-point method and isodesmic reactions) of the electron transfer.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Quinolinas
/
Modelos Moleculares
/
Cobre
/
Complejos de Coordinación
Idioma:
En
Revista:
Chemistry
Asunto de la revista:
QUIMICA
Año:
2017
Tipo del documento:
Article
País de afiliación:
Alemania