School of Chemistry, Center for Synthesis and Chemical Biology, Trinity College Dublin, Dublin 2, Ireland.
Inorg Chem. 2010 Sep 20;49(18):8449-56. doi: 10.1021/ic1010852.
The cyclen-based ligand 1, possessing a [1,10]-phenanthroline moiety as a pendant arm, has been used as a ditopic ligand for the complexation of d- and near infrared (NIR) emitting (and) f-metal ions. This ligand forms kinetically stable complexes, 1·Ln, with lanthanide ions such as Ln = ytterbium, neodymium, and lutetium (formed as a non-IR emitting reference compound), the synthesis and photophysical properties of which are described herein in detail. These 1·Ln complexes were then used as building blocks for the formation of mixed d−f heteropolymetallic self-assemblies, where the phen moiety was used to complex a ruthenium (Ru(II)) ion, giving the d−f3 complexes Ru·Ln3 (Ln = Nd(III), Yb(III), Lu(III)). The formation of these supramolecular coordination conjugates was studied by using absorption and luminescence spectroscopy, while the solution structure of the Ru·Lu3 was elucidated by 1H NMR in D2O and H2O. Of these conjugates, both Ru·Nd3 and Ru·Yb3 displayed an intense NIR-emission in H2O at pH 7.4 (with Q(Yb)(L) = 0.073% and Q(Nd)(L) = 0.040%) and in D2O (with QYbL = 0.23% and Q(Nd)(L) = 0.10%). By comparison with their monometallic analogues Ln·1 (Ln = Nd(III), Yb(III)), we demonstrate that our new design possesses an enhanced sensitization efficiency for lanthanide metal centered sensitization upon using the [Ru(phen)3] moiety (d → f energy transfer) as a visibly exciting antenna, and we demonstrate that the intensity of the Ru(II)-based luminescence strictly correlates to the efficiency of the d → f energy transfer processes.
基于环戊二烯的配体 1 具有作为悬垂臂的[1,10]-菲咯啉部分，已被用作 d-和近红外（NIR）发射（和）f-金属离子的双位点配体。该配体与镧系元素离子（如 Ln = 镱、钕和镥（形成非 IR 发射参考化合物））形成动力学稳定的配合物 1·Ln，本文详细描述了其合成和光物理性质。然后，这些 1·Ln 配合物被用作形成混合 d−f 异多核金属自组装体的构建块，其中 phen 部分用于络合钌（Ru(II)）离子，得到 d−f3 配合物 Ru·Ln3（Ln = Nd(III)、Yb(III)、Lu(III)）。通过吸收和发光光谱研究了这些超分子配位配合物的形成，而 Ru·Lu3 的溶液结构则通过 1H NMR 在 D2O 和 H2O 中阐明。在这些配合物中，Ru·Nd3 和 Ru·Yb3 在 pH 7.4 的 H2O 中（Q(Yb)(L) = 0.073% 和 Q(Nd)(L) = 0.040%）和 D2O 中（QYbL = 0.23% 和 Q(Nd)(L) = 0.10%）均显示出强烈的 NIR 发射。与它们的单核类似物 Ln·1（Ln = Nd(III)、Yb(III)）相比，我们证明了我们的新设计通过使用[Ru(phen)3]部分（d → f 能量转移）作为可见激发天线，提高了镧系金属中心敏化的敏化效率，并且证明了基于 Ru(II)的发光强度与 d → f 能量转移过程的效率严格相关。
