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Inspired by nature, artificial hydrogen bond‐based anion receptors have been developed to achieve high anion selectivity; however, their binding affinity is usually low. The potency of these receptors is usually increased by the introduction of aryl substituents, which withdraw electrons from their binding site through the resonance effect. Here, we show that the polarization of the C(sp3)‐H binding site of bambusuril receptors, and thus their potency to bind anions, can be modulated by the inductive effect. The presence of electron‐withdrawing groups on benzyl substituents of bambusurils significantly increases their binding affinities to halides, resulting in the strongest iodide receptor reported to date with an association constant greater than 1013 M−1 in acetonitrile. A Hammett plot showed that while the bambusuril affinity toward halides linearly increases with the electron‐withdrawing power of their substituents, their binding selectivity remains essentially unchanged. [ABSTRACT FROM AUTHOR]

A novel host−guest recognition motif based on a water-soluble pillar[7]arene ( WP7) and a 2,7-diazapyrenium salt ( DMDAP) was prepared. According to the integrated results of 1H NMR, 2D NOESY, UV-vis spectroscopy and fluorescence titration experiments, we demonstrated that the molecular recognition of WP7 to DMDAP in water not only has high association constant but also has pH-responsiveness. Subsequently, we took advantage of this molecular recognition motif to fabricate a supra-amphiphile based on WP7 and an amphiphilic 2,7-diazapyrenium derivative DAPAC. Its controllable self-assembly in water was also investigated by means of TEM and DLS techniques. [ABSTRACT FROM AUTHOR]