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Updated: Aug 7, 2026

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
Selection between pinching-type and supramolecular polymer-type complexes by alpha-cyclodextrin-beta-cyclodextrin
Hirokazu Takahashi1, Yoshinori Takashima, Hiroyasu Yamaguchi
1Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Abstract:
Novel supramolecular complexes have been prepared from an alpha-cyclodextrin-beta-cyclodextrin hetero-dimer (alpha-CD-beta-CD hetero-dimer) and hetero-cinnamamide guest dimers, G-t-Boc and G-NH2, having adamantyl groups in aqueous solutions. On addition of the competitive guest, the supramolecular structure formed by a mixture of the alpha-CD-beta-CD hetero-dimer and G-t-Boc was found to be different from that of a mixture of the alpha-CD-beta-CD hetero-dimer and G-NH2 by the 1H NMR spectroscopy, the ROESY NMR spectroscopy, and the circular dichroism spectroscopy. The size of the supramolecular complex from the mixture of the alpha-CD-beta-CD hetero-dimer and G-NH2 is larger than that from the mixture of the alpha-CD-beta-CD hetero-dimer and G-t-Boc, which was proved by the pulse field gradient spin-echo NMR and the atomic force microscopy. These results suggest that the mixture of the alpha-CD-beta-CD hetero-dimer and G-t-Boc formed a pinching-type complex, and the mixture of the alpha-CD-beta-CD hetero-dimer and G-NH2 formed a supramolecular polymer-type complex.
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