ISM, UMR CNRS No. 5255, Université de Bordeaux, Talence 33405, France.
LCC, CNRS, 205 Route de Narbonne, Toulouse 31077, France.
Nat Commun. 2014 Apr 1;5:3489. doi: 10.1038/ncomms4489.
Metallodendrimers containing redox-robust centres may have applications in molecular redox recognition, sensing, biosensing and catalysis. So far, however, no metallodendrimer is known in several oxidation states. Here we report metallodendrimers with two electronically communicating iron centres that are stable and isolated in both the Fe(II) and Fe(III) oxidation states, and in addition as class-II mixed-valent Fe(II)Fe(III) complexes. These dendrons are branched to arene-centred dendrimer cores either by Sonogashira coupling or 'click' reactions. The latter reaction involves the introduction of intradendritic 1,2,3-triazolyl ligands, which allows investigation of the selective role of these ligands in intradendritic Au(III) coordination and Au(0) nanoparticle stabilization. As a result, and using the various metallodendrimers with different oxidation states, small Au(0) nanoparticles are intradendritically stabilized by the triazole ligands, whereas with the related non-'click' dendrimers large Au(0) nanoparticles are formed outside the dendrimers and stabilized by a group of dendrimers.
含氧化还原稳定中心的金属树状聚合物在分子氧化还原识别、传感、生物传感和催化方面具有应用。然而，到目前为止，还没有已知的处于多种氧化态的金属树状聚合物。在这里，我们报道了具有两个电子通信铁中心的金属树状聚合物，它们在 Fe(II)和 Fe(III)氧化态以及类 II 混合价态 Fe(II)Fe(III)配合物中都是稳定和隔离的。这些树枝通过 Sonogashira 偶联或“点击”反应连接到芳基中心的树状聚合物核上。后一种反应涉及引入树枝内 1,2,3-三唑配体，这允许研究这些配体在树枝内 Au(III)配位和 Au(0)纳米颗粒稳定化中的选择性作用。结果，并且使用具有不同氧化态的各种金属树状聚合物，小的 Au(0)纳米颗粒通过三唑配体被树枝内稳定化，而对于相关的非“点击”树状聚合物，大的 Au(0)纳米颗粒在树状聚合物外部形成并由一组树状聚合物稳定化。
