We report the synthesis, photophysics, electrochemistry and electrochemiluminescence (ECL) of two dqp (dqp=2,6-di(quinoline-8-yl)pyridine) based ruthenium(II) complexes, bearing either a n-butyl ester (1) or the corresponding carboxylic acid functionality (2). The complexes were prepared from [Ru(dqp)(MeCN)3 ][PF6 ]2 by reaction with the dqp precursor using microwave irradiation. In both cases, photoluminescence spectra present strong 3 MLCT-based red/near-infrared (NIR) emissions centred at about 710 nm. The photoluminescence quantum yields were 6.1 % and 1.8 % for 1 and 2 respectively while the excited state lifetimes were 3.60 μs and 2.37 μs. Both complexes are ECL active, although ECL efficiency (ΦECL ) of 1 was substantially higher than 2, due to its more favourable electrochemical properties. Importantly, 1 also gave strong ECL in aqueous media, which is rare for near-infrared emitters. The results suggest the possibility of very interesting ECL sensing applications for this class of emitter in biological media.

中文翻译：

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水溶液中双链双钌（II）二（喹啉-8-基）吡啶配合物的近红外电化学发光。

我们报告了两个基于dqp（dqp = 2,6-di（quinoline-8-yl）pyridine）的钌（II）配合物的合成，光物理，电化学和电化学发光（ECL），它们带有正丁酯（1）或相应的羧酸官能团（2）。通过使用微波辐射与dqp前体反应，从[Ru（dqp）（MeCN）3] [PF6] 2制备配合物。在这两种情况下，光致发光光谱都呈现出基于3 MLCT的强红色/近红外（NIR）发射，中心波长约为710 nm。1和2的光致发光量子产率分别为6.1％和1.8％，而激发态寿命为3.60μs和2.37μs。两种配合物均具有ECL活性，尽管ECL效率（ΦECL）为1远高于2，这是由于其更有利的电化学性能。重要的，1还可以在水性介质中产生很强的ECL，这对于近红外发射器而言是罕见的。结果表明，对于这种类型的生物介质中的发射器，非常有趣的ECL感测应用可能存在。