An inert Pt(II)âpyridine bond is considerably labilized upon UV irradiation. On the basis of this phenomenon, kinetically inert Pt(II)-linked coordination rings and cages are formed in high yields from their components by obtaining a kinetically distributed mixture and subsequently equilibrating the mixture into the thermodynamically stable structures upon temporary photolabilization. This method is applicable when the pyridine rings in the ligands are not conjugated with other aromatic rings, in good agreement with DFT calculations that indicate the dependency of the photolability on the Ï-conjugation of the ligand frameworks. Interruption of Ï-conjugation either by introducing an methylene linker or by twisting the aromatic rings are effective to accomplish the photo-induced self-assembly.
the self‐assembly process of a Pd4L8 double‐walled square (DWS) from [PdPy*4]2+ (Py*: 3‐chloropyridine used as the leaving ligand on the PdII center) and an organic ditopicligand by QASAP (quantitative analysis of self‐assembly process). DWS is assembled mainly through three pathways. Within 5 minutes of the self‐assembly, all of the substrates, the metal source and the organic ditopicligand, were
我们研究了由[PdPy * 4 ] 2+(Py *:3-氯吡啶用作Pd II中心的离去配体)的Pd 4 L 8双壁方形(DWS)的自组装过程通过QASAP进行配体(自组装过程的定量分析)。DWS主要通过三个途径进行组装。自组装后5分钟内,所有底物,金属来源和有机二位配体被完全消耗,并转化为主要中间体。在2小时内,主要中间体提供了30%的DWS,200纳米大小的大型中间体和相对稳定的瞬态中间体。通过NMR和质量测量将该稳定的中间体表征为动力学捕获的Pd 3 L 6双层三角形(DWT)。从2小时到1天,借助于Py *,由200 nm大小的大中间体形成了19%的DWS,而Py *并不是最终组装的组成部分。1天后,其余的大型中间体和DWT提供了39%的DWS再次借助Py *。这种自组装过程与以前报道的单壁大环化合物完全不同,并且自组装途径的变化将来自对位配体灵活性的差异。这项研究揭示了DWS自组装过程的复杂性,而不是简单的单一途径。
Supramolecular Two-dimensional Arrays with Phenyl/Perfluorophenyl Interactions Constructed from One-dimensional Coordination Polymers
作者:Kayoko Kasai
DOI:10.1246/cl.2006.54
日期:2006.1
Supramolecular assembly of Cd(NO3)2, aniline derivatives and fluorinated ligand 1,4-bis(4-pyridylmethyl)-2,3,5,6-tetrafluorobenzene (bpf) afforded one-dimensional coordination polymers [Cd(bpf)(aniline)2(NO3)2]n (1), [Cd(bpf)(p-toluidine)2(NO3)2]n (2), and [Cd(bpf)(p-bromoaniline)2(NO3)2]·(p-bromoaniline)2}n (3). The 1D polymers of 1 and 2 were connected through phenyl/perfluorophenyl interaction to give supramolecular two-dimensional arrays while no such interaction in 3 due to the bulky Br group.
self-assembly process of a Pd4L8 double-walled square (DWS) was investigated. As was seen in Pd2L4 cages, Pd(II)-linked coordination self-assembly processes are generally affected by the rigidity of multitopic ligands. However, the self-assembly of a Pd4L8 DWS from rigid ditopic ligands took place with the formation of two kinds of metastable species [submicrometer-sized species and a Pd3L6 double-walled triangle
研究了Pd 4 L 8双层正方形(DWS)的自组装过程。如在Pd 2 L 4笼子中所见,Pd(II)连接的配位自组装过程通常受多位配体刚性的影响。然而,由刚性的对位配体自组装的Pd 4 L 8 DWS发生了两种亚稳态物种[亚微米大小的物种和Pd 3 L 6双壁三角形(DWT)]的形成。该结果表明,DWS的自组装过程很大程度上受最终产物的几何形状的影响,而不受二位配体的几何形状的影响。