A Structure-Adaptive Ligand: The Conformation Changes to Fit with the Lengths and Angles of Tetravalent Bis-Paraquat Guests

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( 1)H NMR revealed that 1b has versatile complexing properties with respect to tetravalent cationic guests used despite the guest molecules' length and shape.

Automated summary

A flexible cylindrical cryptand (1b) with two m-phenylene-26-crown-8 ethers has been found to have versatile complexing properties with respect to tetravalent cationic guests despite their differences in length and shape, according to diffusion-ordered spectroscopy nuclear magnetic resonance (NMR) and titration experiments.