Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | Shunichi Fukuzumi | * |
dc.contributor.author | Kei Okubo | * |
dc.date.accessioned | 2016-08-27T04:08:41Z | - |
dc.date.available | 2016-08-27T04:08:41Z | - |
dc.date.issued | 2015 | * |
dc.identifier.issn | 0002-7863 | * |
dc.identifier.other | OAK-16209 | * |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/217927 | - |
dc.description.abstract | Photo excitation of end-on trans-mu-1,2-peroxodicopper(II) complex [(tmpa)(2)Cu-2(II)(O-2)](2+) (1) (lambda(max) = 525 and 600 nm) and side-on mu-eta(2):eta(2)-peroxodicopper(II) complexes [(NS)Cu-2(II)(O-2)](2+) (2) and [(N3)Cu-2(II)(O-2)](2+) (3) at -80 degrees C in acetone led to one-photon two-electron peroxide-to-dioxygen oxidation chemistry (O-2(2-) + hv -> O-2 + 2e(-)). Interestingly, light excitation of 2 and 3 (having side-on mu-eta(2):eta(2)-peroxo ligation) led to release of dioxygen, while photoexcitation of 1 (having an end-on trans-1,2-peroxo geometry) did not, even though spectroscopic studies revealed that both reactions proceeded through previously unknown mixed-valent superoxide species: [CuII(O-2(center dot-))Cu-I](2+) (lambda(max) = 685-740 nm). For 1, this intermediate underwent further fast intramolecular electron transfer to yield an "O-2-caged" dicopper(I) adduct, Cu-2(I)-O-2, and a barrierless stepwise back electron transfer to regenerate 1 occurred. Femtosecond laser excitation of 2 and 3 under the same conditions still led to [Cu-II(O-2(center dot-))Cu-I](2+) intermediates that, instead, underwent O-2 release with a quantum yield of 0.14 +/- 0.1 for 3. Such remarkable differences in reaction pathways likely result from the well-known ligand-derived stability of 2 and 3 vs 1 indicated by ligand-Cu-II/I redox potentials; (N5)Cu-I and (N3)Cu-I complexes are far more stable than (tmpa)Cu-I species. The fast Cu-2(I)/O-2 rebinding kinetics was also measured after photoexcitation of 2 and 3, with the results closely tracking those known for the dicopper proteins hemocyanin and tyrosinase, for which the synthetic dicopper(I) precursors [(N5)Cu-2(I)](2+) and [(N3)Cu-2(I)](2+) and their dioxygen adducts serve as models. The biological relevance of the present findings is discussed, including the potential impact on the solar water splitting process. | * |
dc.language | English | * |
dc.publisher | AMER CHEMICAL SOC | * |
dc.title | Laser-Induced Dynamics of Peroxodicopper(II) Complexes Vary with the Ligand Architecture. One-Photon Two-Electron O-2 Ejection and Formation of Mixed-Valent (CuCuII)-Cu-I-Superoxide Intermediates | * |
dc.type | Article | * |
dc.relation.issue | 50 | * |
dc.relation.volume | 137 | * |
dc.relation.index | SCI | * |
dc.relation.index | SCIE | * |
dc.relation.index | SCOPUS | * |
dc.relation.startpage | 15865 | * |
dc.relation.lastpage | 15874 | * |
dc.relation.journaltitle | JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | * |
dc.identifier.doi | 10.1021/jacs.5b10177 | * |
dc.identifier.wosid | WOS:000367562800045 | * |
dc.identifier.scopusid | 2-s2.0-84952802823 | * |
dc.author.google | Saracini, Claudio | * |
dc.author.google | Ohkubo, Kei | * |
dc.author.google | Suenobu, Tomoyoshi | * |
dc.author.google | Meyer, Gerald J. | * |
dc.author.google | Karlin, Kenneth D. | * |
dc.author.google | Fukuzumi, Shunichi | * |
dc.contributor.scopusid | Shunichi Fukuzumi(35430038100;58409757400) | * |
dc.contributor.scopusid | Kei Okubo(7101788990) | * |
dc.date.modifydate | 20240401081001 | * |