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  • 1,3,5–2,4,6‐Functionalized Benzene Molecular Cage: An Environmentally Responsive Scaffold that Supports Hierarchical Superstructures
Title: 1,3,5–2,4,6‐Functionalized Benzene Molecular Cage: An Environmentally Responsive Scaffold that Supports Hierarchical Superstructures
Abstract New stimulus‐responsive scaffolds are of interest as constituents of hierarchical supramolecular ensembles. 1,3,5–2,4,6‐Functionalized, facially segregated benzene moieties have a time‐honored role as building blocks for host molecules. However, their user as switchable motifs in the construction of multi‐component supramolecular structures remains poorly explored. Here, we report a molecular cage 1, which consists of a bent anthracene dimer3paired with 1,3,5‐tris(aminomethyl)‐2,4,6‐triethylbenzene2. As the result of the pH‐inducedababab↔bababaisomerization of the constituent‐functionalized benzene units derived from2, this cage can reversibly convert between an open state and a closed form, both in solution and in the solid state. Cage 1was used to create stimuli‐responsive hierarchical superstructures, namely Russian doll‐like complexes with [K⊂18‐crown‐6⊂1]+and [K⊂cryptand‐222⊂1]+. The reversible assembly and disassembly of these superstructures could be induced by switching cage 1from its open to closed form. The present study thus provides an unusual example where pH‐triggered conformation motion within a cage‐like scaffold is used to control the formation and disassociation of hierarchical ensembles.  more » « less
Award ID(s):
2304731
PAR ID:
10532462
Author(s) / Creator(s):
; ; ; ; ; ;
Editor(s):
Kueckmann, Theresa; Maas, Frank; Su, Xin; Tobey, Suzanne; Welckgenannt, Nathalie
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Angewandte Chemie International Edition
ISSN:
1433-7851
Page Range / eLocation ID:
e202407805
Subject(s) / Keyword(s):
Molecular cage environmentally responsive superstructures
Format(s):
Medium: X Other: pdf
Sponsoring Org:
National Science Foundation
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