作者:Ian S. Tidmarsh、Thomas B. Faust、Harry Adams、Lindsay P. Harding、Luca Russo、William Clegg、Michael D. Ward
DOI:10.1021/ja805605y
日期:2008.11.12
8(L (naph)) 12} (16+) retain their structural integrity in polar solvents, in contrast to the cagesM 8(L (anth)) 12} (16+) which dissociate in polar solvents. Consequently, the cagesM 8(L (naph)) 12} (16+) give NMR spectra in agreement with the symmetry observed in the solid state, and their fluorescence spectra (for M = Cd) display (in addition to the normal naphthalene-based pi-pi* fluorescence)
已经制备了两个新的双二齿桥连配体,L(萘)和 L(蒽),它们包含两个螯合吡唑基-吡啶单元,连接到一个芳族间隔基(naphthalene-1,5-diyl 和 anthracene-9,10-diyl分别)通过亚甲基连接器。这些中的每一个都与具有八面体配位几何结构偏好的过渡金属离子反应以提供M 8L 12} (16+)笼(对于L(蒽),M = Cu,Zn;对于L(萘),M = Co, Ni, Cd) 具有近似立方排列的金属离子,桥接配体跨越十二个边缘中的每一个,以及包含阴离子和/或溶剂分子混合物的大中心腔。基于 L (anth) 的笼子具有两个具有相反手性的环状螺旋 M 4L 4} 面,通过四个额外的 L (anth) 配体作为“支柱”连接;所有金属中心都具有经向三螯合构型。相比之下,基于 L (naph) 的笼子具有(非晶体学)S 6 对称性,对角对角具有面三螯构型,其他六个是子午线。两种结构之间的另一个显着差异是含有
Shape-, Size-, and Functional Group-Selective Binding of Small Organic Guests in a Paramagnetic Coordination Cage
作者:Simon Turega、Martina Whitehead、Benjamin R. Hall、Anthony J. H. M. Meijer、Christopher A. Hunter、Michael D. Ward
DOI:10.1021/ic302498t
日期:2013.1.18
coordination cage [Co8L12]16+ (where L is a bridging ligand containing two chelating pyrazolyl-pyridine units connected to a central naphthalene-1,5-diyl spacer via methylene “hinges”) has been investigated in detail by 1H NMR spectroscopy. The cage encloses a cavity of volume of ca. 400 Å3, which is accessible through 4 Å diameter portals in the centers of the cube faces. The paramagnetism of the cage eliminates
八核立方配位笼[Co 8 L 12 ] 16+的主体-客体化学性质(其中L是包含两个螯合吡唑基-吡啶单元的桥连配体,它们通过亚甲基“铰链”连接至中央萘-1,5-二基间隔基)已通过1 H NMR光谱进行了详细研究。笼子围成一个容积为ca的空腔。400埃3,这是通过在立方体的表面的中心4个的直径门户访问。保持架的顺磁性通过将NMR信号分散在大约一个范围内,从而消除了NMR信号的重叠。200 ppm,使得易于观察到特定信号的变化,并且还导致络合宾客的大络合物诱导的移动。笼子,CD 3CN溶液可作为小型有机客体(如香豆素(K = 78 M – 1))和其他具有类似大小和形状的双环分子(如异喹啉-N-氧化物(K = 2100 M )的大小和形状选择宿主–1)。结合来自两个独立的识别元素,它们已经被分别量化。它们是:(i)从所述H-键的相互作用接受客户的氧原子与会聚基团CH质子的腔体内部产生的极性成分
Stepwise assembly of mixed-metal coordination cages containing both kinetically inert and kinetically labile metal ions: introduction of metal-centred redox and photophysical activity at specific sites
作者:Ashley B. Wragg、Alexander J. Metherell、William Cullen、Michael D. Ward
DOI:10.1039/c5dt02957k
日期:——
each ligand is bound to the metal ion, such that the complex has three pendant bidentate sites at which cageassembly can propagate by coordination to additional labile ions Mb in a separate step. Thus, combination of four [(Ma)L3]2+ units and four [Mb]2+ ions results in assembly of the complete cages [(Ma)4(Mb)4L12]16+ in which a metal ion lies at each of the eight vertices, and a bridging ligand spans
据报道逐步制备了杂金属八核配位笼[(M a)4(M b)4 L 12 ] 16+,其中M a = Ru或Os,M b = Cd或Co(均处于+2氧化态) )。这需要初步制备动力学惰性的单核复合物[(M a)L 3 ] 2+,其中L是具有两个双齿螯合吡唑基-吡啶单元的对位配体:在复合物中[(M a)L 3 ] 2+每个配体的一个末端与金属离子结合,使得络合物具有三个悬垂的双齿位点,笼子组件可以在单独的步骤中通过配位而传播至另外的不稳定离子M b上。因此,四个[(M a)L 3 ] 2+单元和四个[M b ] 2+离子的组合导致组装完整的笼子[(M a)4(M b)4 L 12 ] 16+其中一个金属离子位于八个顶点中的每个顶点上,并且一个桥接配体跨越了一个立方体的十二个边缘中的每个顶点。不同类型的金属离子必须在外围交替排列,每种桥联配体均与每种类型的一种金属离子键合。所有四个笼子都具有结构特征:在Ru(II)/
Stepwise synthesis of a Ru<sub>4</sub>Cd<sub>4</sub> coordination cage using inert and labile subcomponents: introduction of redox activity at specific sites
作者:Alexander J. Metherell、Michael D. Ward
DOI:10.1039/c4cc02627f
日期:——
Combination of four [RuL3]2+ units, each with three pendant binding sites, and four Cd2+ ions affords the redox-active, heteronuclear, cubic cage [Ru4Cd4L12]16+.
One Guest or Two? A Crystallographic and Solution Study of Guest Binding in a Cubic Coordination Cage
作者:Christopher G. P. Taylor、Stephen P. Argent、Michael D. Ludden、Jerico R. Piper、Cristina Mozaceanu、Sarah A. Barnett、Michael D. Ward
DOI:10.1002/chem.201905499
日期:2020.3.9
despite the fact that solution titrations are consistent with 1:1 complex formation, and the combined volume of the pair of guests significantly exceeds the Rebek 55±9 % packing for optimal guest binding, with packing coefficients of up to 87 %. Re-examination of solution titrationdata for guest binding in two cases showed that, although conventional fluorescence titrations are consistent with 1:1 binding