Photoinduced NO release by visible light irradiation from pyrazine-bridged nitrosyl ruthenium complexes.

J Am Chem Soc

Departamento de Química da Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. dos Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil.

Published: December 2003

The binuclear complex [RuII(NH3)5(pz)RuII(bpy)2(NO)](PF6)5 was prepared and characterized by elemental analysis, UV-vis, and IR spectroscopy. The complex UV-vis spectrum has presented bands at 242, 286, and 530 nm in acetate buffer solution at pH 4.5. The photochemical study by laser flash-photolysis at 532 nm showed the NO release account from the NO measured by a NO sensor. The quantum yield for NO release (0.025 +/- 0.004 mol einsten-1) was determined with a laser flash-photolysis apparatus (Continuum Q-switched Nd:YAG laser). The major irradiation product of the [RuII(NH3)5(pz)RuII(bpy)2(NO)]5+ complex besides nitric oxide is [RuIII(NH3)5(pz)RuII(bpy)2(H2O)]5+.

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http://dx.doi.org/10.1021/ja0376801DOI Listing

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