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Multiple Stimuli-Responsive Conformational Exchanges of Biphen[3]arene Macrocycle.

ABSTRACT: Conformational exchanges of synthetic macrocyclic acceptors are rather fast, which is rarely studied in the absence of guests. Here, we report multiple stimuli-responsive conformational exchanges between two preexisting conformations of 2,2',4,4'-tetramethoxyl biphen[3]arene (MeBP3) macrocycle. Structures of these two conformations are both observed in solid state, and characterized by ¹H NMR, ¹³C NMR and 2D NMR in solution. In particular, conformational exchanges can respond to solvents, temperatures, guest binding and acid/base addition. The current system may have a role to play in the construction of molecular switches and other stimuli-responsive systems.

SUBMITTER: Wang Y

PROVIDER: S-EPMC7762528 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Multiple Stimuli-Responsive Conformational Exchanges of Biphen[3]arene Macrocycle.

Wang Yiliang Y Yang Liu-Pan LP Zhao Xiang X Cui Lei L Li Jian J Jia Xueshun X Fang Jianhui J Li Chunju C

Molecules (Basel, Switzerland) 20201208 24

Conformational exchanges of synthetic macrocyclic acceptors are rather fast, which is rarely studied in the absence of guests. Here, we report multiple stimuli-responsive conformational exchanges between two preexisting conformations of 2,2',4,4'-tetramethoxyl biphen[3]arene (MeBP3) macrocycle. Structures of these two conformations are both observed in solid state, and characterized by <sup>1</sup>H NMR, <sup>13</sup>C NMR and 2D NMR in solution. In particular, conformational exchanges can respo ...[more]

PMID: 33302382

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