Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Ruthenium polypyridine complexes. On the route to biomimetic assemblies asmodels for the photosynthetic reaction center
Autore:
Durr, H; Bossmann, S;
Indirizzi:
Univ Saarland, Fak Organ Chem 8 12, D-66041 Saarbrucken, Germany Univ Saarland Saarbrucken Germany D-66041 , D-66041 Saarbrucken, Germany Univ Karlsruhe, Engler Bunte Inst, D-76128 Karlsruhe, Germany Univ Karlsruhe Karlsruhe Germany D-76128 nst, D-76128 Karlsruhe, Germany
Titolo Testata:
ACCOUNTS OF CHEMICAL RESEARCH
fascicolo: 11, volume: 34, anno: 2001,
pagine: 905 - 917
SICI:
0001-4842(200111)34:11<905:RPCOTR>2.0.ZU;2-J
Fonte:
ISI
Lingua:
ENG
Soggetto:
PHOTOINDUCED ELECTRON-TRANSFER; ARTIFICIAL PHOTOSYNTHESIS; SUPRAMOLECULAR ASSEMBLIES; CHARGE SEPARATION; SYSTEMS; LIGHT; SENSITIZERS; ACCEPTOR; WATER; TRIAD;
Tipo documento:
Review
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Physical, Chemical & Earth Sciences
Citazioni:
53
Recensione:
Indirizzi per estratti:
Indirizzo: Durr, H Univ Saarland, Fak Organ Chem 8 12, D-66041 Saarbrucken, Germany Univ Saarland Saarbrucken Germany D-66041 1 Saarbrucken, Germany
Citazione:
H. Durr e S. Bossmann, "Ruthenium polypyridine complexes. On the route to biomimetic assemblies asmodels for the photosynthetic reaction center", ACC CHEM RE, 34(11), 2001, pp. 905-917

Abstract

We describe in this Account the preparation of RuL3 complexes and their significance as biomimetic models for the photosynthetic reation center. Their preparation from simple or more complicated bypyridine ligands L and their photophysical data, especially their stability, are reported. Biomimetic models involving three concepts of the interaction of RuL3 with acceptors in coordinatively, mechanically, or covalently linked supramolecular assemblies are also presented. The electron transfer (ET) of the noncovalently linked assemblies of RuL3 complexes carrying polyether chains with one or two anisyl binding sites (4 or 5) with the cyclic bisviologen was studied. Molecular modeling and NMR titration clearly show the formation of supramolecular assemblies. Time-resolved spectroscopy demonstrated that ET and charge separation in the RuL3 complexes with two binding sites are more efficient. The more constrained RuL3-bisviologen-catenane (6) possesses two conformations which exhibit different efficiency in ET, creating a charge-separated state in the microsecond domain. The covalently linked Ru(bpy)(3)(2+)-viologen assemblies having one (7, diad) or two bisviologen arms (8, diad) resultin efficient ET. Addition of linear polyethers, cyclic polyethers, or crowns generates new triads and tetrads of the pseudorotaxane type. Molecular modeling and NMR titration clearly indicate the formation of supramolecular assemblies. The analysis of time-resolved studies proves fast ET and especially long-lived charge-separated states in these pseudorotaxanes. These data, compared with the findings for the photosynthetic reation center, show conclusive results. The lifetimes of the charge-separated states increase clearly in the sequence for noncovalently < mechanically < and covalently linked assemblies.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 25/09/20 alle ore 21:26:02