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Title: Solvent-responsive cavitand lanthanum complex
Stimuli-responsive supramolecular assemblies are dynamic systems that can reversibly switch between different states upon external stimuli. In this context, metal coordination offers a reliable strategy for the preparation of stimuli responsive supramolecular architectures. Herein we report the preparation of a solvent-responsive cavitand-lanthanum coordination complex. A tetra-phosphonate cavitand has been functionalized with four hydroxyl moieties at the upper rim to form a pre-organized octadentate ligand capable of binding lanthanum salts. Exploiting the orthogonal recognition sites, two different complex architectures are formed in acetonitrile and acetone, respectively. The complexes have been characterized in solution by NMR spectroscopy, ITC experiments, while at the solid state, the single crystal structure of the acetonitrile derivative has been determined. Furthermore, as observed by DOSY-NMR spectroscopy, small quantities of acetone in acetonitrile are sufficient to trigger assembly interconversion.  more » « less
Award ID(s):
1809740
PAR ID:
10148033
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
48
Issue:
36
ISSN:
1477-9226
Page Range / eLocation ID:
13732 to 13739
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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