PDF(Pubmed)
Abstract：
A strategy to engineer the stacking of diketopyrrolopyrrole (DPP) dyes based on non-statistical metallosupramolecular self-assembly is introduced. For this, the DPP backbone is equipped with nitrogen-based donors that allow for different discrete assemblies to be formed upon the addition of Pd(II), distinguished by the number of π-stacked chromophores. A Pd3 L6 three-ring, a heteroleptic Pd2 L2 L\'2 ravel composed of two crossing DPPs (flanked by two carbazoles), and two unprecedented self-penetrated motifs (a Pd2 L3 triple and a Pd2 L4 quadruple stack), were obtained and systematically investigated. With increasing counts of stacked chromophores, UV/Vis absorptions red-shift and emission intensities decrease, except for compound Pd2 L2 L\'2 , which stands out with an exceptional photoluminescence quantum yield of 51 %. This is extraordinary for open-shell metal containing assemblies and explainable by an intra-assembly FRET process. The modular design and synthesis of soluble multi-chromophore building blocks offers the potential for the preparation of nanodevices and materials with applications in sensing, photo-redox catalysis and optics.
摘要：
介绍了一种基于非统计金属超分子自组装的二酮吡咯（DPP）染料堆叠的策略。因此,DPP骨架配备有基于氮的供体，允许在添加Pd（II）时形成不同的离散组件，通过π堆叠的发色团的数量来区分。一个Pd3L6三环，由两个交叉DPP组成的杂合Pd2L2L\'2ravel（两侧是两个咔唑），和两个前所未有的自穿透图案（Pd2L3三重和Pd2L4四重堆栈），获得并进行了系统研究。随着堆积发色团数量的增加，紫外-可见吸收红移和发射强度降低，除了化合物Pd2L2L'2之外，该化合物以52％的优异光致发光量子产率脱颖而出。这对于包含开壳金属的组件来说是非同寻常的，并且可以通过内部组装FRET过程来解释。可溶性多发色团结构单元的模块化设计和合成为制备具有传感应用的纳米器件和材料开辟了潜力。光-氧化还原催化和光学。
