Photochemistry of nickel salen based complexes and relevance to catalysis

• Tipo: Artigo em Revista Científica Internacional
• Data: 2002

Autores

de Castro, B (Autor) FCUP; Ferreira, R (Autor) Outra; Freire, C (Autor) FCUP; Garcia, H (Autor) Outra; Palomares, EJ (Autor) Outra; Sabater, MJ (Autor) Outra

Revista

Título: New Journal of Chemistry

Vol. 26

Páginas: 405-410

ISSN: 1144-0546

Editora: Royal Society of Chemistry

Indexação

ISI Web of Knowledge - 11 Citações

Scopus - 15 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-000-RNK

DOI: 10.1039/b108436d

Abstract (EN): A series of four nickel salen complexes have been synthesised and their photochemical properties studied. These complexes emit in hexane at lambda(em) 580 nm with similar quantum efficiencies. Fluorescence decay occurs on the nanosecond time scale and its intensity is quenched by oxygen except for the complex with the shortest lifetime. For all complexes laser ash photolysis in CH2Cl2 or hexane generates a transient (lifetime on the mus time scale) that was assigned to a Ni-to-ligand electron transfer triplet excited state. In an attempt to show the relevance of photochemical data to catalysis, epoxidation of beta-methylstyrene was carried out in the presence of the four complexes. It was found that the activity of the complexes correlates with the lifetime of the triplet charge-separated state. This relationship was interpreted as reflecting the intrinsic stability of the oxidised Ni ion in the different complexes, which is the common link between the photochemical and catalytic experiments.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6