Laboratoire de Synthèse des Assemblages Moléculaires Multifonctionnels, Institut de Chimie de Strasbourg, CNRS/UMR 7177, Université de Strasbourg, 4, rue Blaise Pascal, 67000, Strasbourg, France.
Inorganic Materials Chemistry Research Group, Laboratory of Materials Chemistry and Chemical Analysis, Department of Chemistry, University of Turku, 20014, Turku, Finland.
Chemistry. 2019 Jan 28;25(6):1481-1487. doi: 10.1002/chem.201805498. Epub 2019 Jan 7.
The allosteric control of the receptor properties of two flexible covalent cages is reported. These receptors consist of two zinc(II) porphyrins connected by four linkers of two different sizes, each incorporating two 1,2,3-triazolyl ligands. Silver(I) ions act as effectors, responsible for an on/off encapsulation mechanism of neutral guest molecules. Binding silver(I) ions to the triazoles opens the cages and triggers the coordination of pyrazine or the encapsulation of N,N'-dibutyl-1,4,5,8-naphthalene diimide. The X-ray structure of the silver(I)-complexed receptor with short connectors is reported, revealing the hollow structure with a cavity well-defined by two eclipsed porphyrins. Rather unexpectedly, the crystallographic structure of this receptor with pyrazine as a guest molecule showed that the cavity is occupied by two pyrazines, each binding to the zinc(II) porphyrin in a monotopic fashion.
报道了两种柔性共价笼状化合物的受体性质的变构控制。这些受体由两个锌（II）卟啉通过两个不同大小的四个连接体连接而成，每个连接体都包含两个 1,2,3-三唑基配体。银（I）离子作为效应物，负责中性客体分子的开/关包封机制。与三唑结合的银（I）离子打开笼状结构并引发吡嗪的配位或 N,N'-二丁基-1,4,5,8-萘二酰亚胺的包封。报道了具有短连接器的银（I）配合物受体的 X 射线结构，揭示了由两个重叠卟啉限定的空腔的空心结构。出人意料的是，作为客体分子的吡嗪存在时，该受体的晶体结构表明空腔被两个吡嗪占据，每个吡嗪以单拓扑方式与锌（II）卟啉结合。
