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A Structure-Adaptive Ligand: The Conformation Changes to Fit with the Lengths and Angles of Tetravalent Bis-Paraquat
Yoichi Habata, Yuka Matsumoto, Hiroki Horita
1Department of Chemistry, Education Center, Faculty of Engineering, Chiba Institute of Technology, Shibazono, Narashino, Chiba 275-0023, Japan.
Abstract:
A flexible cylindrical cryptand (1b) with two m-phenylene-26-crown-8 ethers has been prepared, and its complexing properties with respect to tetravalent cationic bis-paraquat guests have been investigated. Diffusion-ordered spectroscopy nuclear magnetic resonance (NMR) and titration experiments using cold electrospray ionization mass spectrometry and 1H NMR revealed that 1b has versatile complexing properties with respect to tetravalent cationic guests used despite the guest molecules' length and shape.
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