Wu J, Sun X, Li X, Li X, Feng W, Yuan L. Multi-Responsive Molecular Encapsulation and Release Based on Hydrogen-Bonded Azo-Macrocycle.
Molecules 2023;
28:molecules28114437. [PMID:
37298912 DOI:
10.3390/molecules28114437]
[Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/27/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
Research on stimuli-responsive host-guest systems is at the cutting edge of supramolecular chemistry, owing to their numerous potential applications such as catalysis, molecular machines, and drug delivery. Herein, we present a multi-responsive host-guest system comprising azo-macrocycle 1 and 4,4'-bipyridinium salt G1 for pH-, photo-, and cation- responsiveness. Previously, we reported a novel hydrogen-bonded azo-macrocycle 1. The size of this host can be controlled through light-induced E↔Z photo-isomerization of the constituent azo-benzenes. The host is found in this work to be capable of forming stable complexes with bipyridinium/pyridinium salts, and implementing guest capture and release with G1 under light in a controlled manner. The binding and release of the guest in the complexes can also be easily controlled reversibly by using acid and base. Moreover, the cation competition-induced dissociation of the complex 1a2⊃G1 is achieved. These findings are expected to be useful in regulating encapsulation for sophisticated supramolecular systems.
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