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化学・物質工学セミナー"Guest-binding and Structural Reorganization in Stimuli-responsive
Coordination Cages"
日時：平成28年1月28日（木）14:30～16:00
場所：総合教育研究棟 多目的ホール
Guido H. Clever
講演題目；Guest-bindingandStructuralReorganizationin Stimuli-responsive
Technische Universität
Dortmund,Fakultät
für Chemie und ChemischeBiologie,
Otto-Hahn-Str. 6, 44227 Dortmund, Germany
Coordination Cages
講演者；Guido H. Clever 教授（ドルトムント工科大学）
E-mail: guido.clever@tu-dortmund.de
Banana-shaped bis-monodentate ligands form the basis of a family of coordination cages whosemembers show variable topologies, a rich encapsulation chemistry and several functionalfeatures.[1] Among these, switchable host-guest systems are of particular interest because they
promise to find application in fields such as uptake & release of molecular cargo, sensing andseparation as well as catalysis inside confined molecular environments. Our current research
efforts focus on the triggering of structural reorganizations and the implementation of reversible
control over the size and shape of the cages’ internal cavities.
Previously, we have reported a dibenzosuberone-based interpenetrated double-cage[Pd4Ligand8] which is capable of allosteric anion binding with a tremendous affinity for theinclusion of two chloride anions in its outer pockets.[2] Subsequently, the anion selectivity of thecages could be adjusted by the size of the anionic template in the central pocket.[3] In contrast,
another double-cage derivative was now shown to bind neutral guests inside its central pocket
upon activation with halide anions (Fig. c).[4] Yet another example allowed for switching of theoverall cage architecture (monomeric vs. dimeric vs. triple-catenated, Fig. a-b) by gradually
increasing the concentration of anionic triggers.[5] Based on this work, we further showed, thatthe interpenetration principle can be extended onto other functional backbones such as theelectron donor phenothiazine.[6] In mixed-ligand cages containing additional ligands that serve
as electron acceptors, light-induced charge transfer could be observed by pump-probe
spectroscopy. In another example, light of different wavelengths was used as a trigger toreversibly switch guest uptake and release in a photochromic coordination cage based on
dithienylethene (DTE) ligands.[7] Upon slight changes in the ligand design, light was shown to
induce a complete structural reorganization of the self-assembled system.

References[1] M. Han, D. M. Engelhard, G. H. Clever, Chem. Soc. Rev. 2014, 43, 1848.
[2] S. Freye, J. Hey, A. Torras-Galán, D. Stalke, R. Herbst-Irmer, M. John, G. H. Clever, Angew. Chem.
Int. Ed. 2012, 51, 2191.
[3] S. Freye, R. Michel, D. Stalke, M. Pawliczek, H. Frauendorf, G. H. Clever, J. Am. Chem. Soc. 2013,135, 8476.
[4] S. Löffler, J. Lübben, L. Krause, D. Stalke, B. Dittrich, G. H. Clever, J. Am. Chem. Soc. 2015, 137,1060.
[5] R. Zhu, J. Lübben, B. Dittrich, G. H. Clever, Angew. Chem. Int. Ed. 2015, 54, 2796.
[6] M. Frank, J. Hey, I. Balcioglu, Y.-S. Chen, D. Stalke, T. Suenobu, S. Fukuzumi, H. Frauendorf, G.
H. Clever, Angew. Chem. Int. Ed. 2013, 52, 10102.
[7] M. Han, R. Michel, B. He, Y.-S. Chen, D. Stalke, M. John, G. H. Clever, Angew. Chem. Int. Ed.
2013, 52, 1319.

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