Video Experimental Relacionado

Updated: Jan 13, 2026

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction

Published on: August 23, 2018

Conjuntos anfitrion-huésped multicapa dependientes de cationes formados por un macrociclo de níquel(II) a base de

Shigehisa Akine^1,2, Masato Nakano², Yoko Sakata³

¹Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa, Japan.

Chemistry (Weinheim an der Bergstrasse, Germany)

|January 7, 2026

Abstract:

A planar bis(saloph) nickel(II) macrocyclic host, L^2bNi₂, incorporating xanthene motifs and hexyl side chains, was synthesized to provide structural rigidity and solubility. Its ion recognition behavior toward alkali metal ions was investigated by ¹H NMR titration, mass spectrometry, and X-ray crystallography. With Na⁺, a 2:1 (host/guest) sandwich-type complex was formed at 0.5 equiv, which shifted to a monomeric 1:1 complex upon further Na⁺ addition. In contrast, larger alkali metal ions such as K⁺, Rb⁺, and Cs⁺ formed stable 2:1 (host/guest) dimeric complexes, whose sandwich structures remained intact even in the presence of excess cation, resulting in the formation of 2:2, 2:3, and 3:2 higher-order assemblies, unlike those of previously reported related macrocycles. X-ray analyses revealed a rare hexagonal planar coordination for Na⁺ and orthogonally stacked dimeric structures for the larger cations. Theoretical calculations support the experimental trends, showing that larger alkali metal ions favor 2:1 complexation due to reduced repulsive interactions between the metallomacrocycles. These findings demonstrate that the aggregation behavior of the metallomacrocycle is sensitively tuned by the size and coordination preferences of guest cations, highlighting the utility of preorganized, metal-based macrocycles in constructing dynamic, multivalent supramolecular architectures.

Palabras clave:

metales alcalinos sistemas anfitrión-huésped macrociclos níquel interacciones de apilamiento

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