Acidity and photolability of ruthenium salen nitrosyl and aquo complexes in aqueous solutions

被引:21
作者
Bordini, J. [1 ]
Novaes, D. O. [2 ]
Borissevitch, I. E. [2 ]
Owens, B. T. [3 ]
Ford, P. C. [3 ]
Tfouni, E. [1 ]
机构
[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Pret, Dept Quim, BR-14040901 Ribeirao Preto, SP, Brazil
[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Pret, Dept Fis & Mat, BR-14040901 Ribeirao Preto, SP, Brazil
[3] Univ Calif Santa Barbara, Dept Chem & Biochem, Santa Barbara, CA 93106 USA
基金
美国国家科学基金会; 巴西圣保罗研究基金会;
关键词
chloride; photolability; photorelease; ruthenium; salen; Schiff base; nitrosyl; complexes; photochemistry; nitric oxide; donor; nitrosonium; acidity; coordinated water; sequential photoreactions;
D O I
10.1016/j.ica.2007.11.018
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The photochemical behavior of nitrosyl complexes Ru(salen)(NO)(OH(2))(+) and Ru(salen)(NO) Cl (salen = N, N'-ethylenebis-(salicylideneiminato) dianion) in aqueous solution is described. Irradiation with light in the 350-450 nm range resulted in nitric oxide (NO) release from both. For Ru(salen)(NO) Cl secondary photoreactions also resulted in chloride aquation. Thus, in both cases the final photoproduct is the diaquo cation Ru(III) (salen) (OH(2))(2)(+), for which pK(a)'s of 5.9 and 9.1 were determined for the coordinated waters. The pK(a) of the Ru(salen)(NO)(OH(2))+ cation was also determined as 4.5 +/- 0.1, and the relative acidities of these ruthenium aquo units are discussed in the context of the bonding interactions between Ru(III) and NO. (C) 2007 Elsevier B.V. All rights reserved.
引用
收藏
页码:2252 / 2258
页数:7
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