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A mutually stabilized host-guest pair.

ABSTRACT: By using click chemistry, a hexacationic cage was synthesized. The cage contains two triscationic ?-electron-deficient trispyridiniumtriazine (TPZ3+) platforms that are bridged in a face-to-face manner by three ethylene-triazole-ethylene linkers. A diversity of ?-electron-rich guests can be recognized within the pocket of the cage, driven by host-guest ?-? interactions. The cage cavity acts as a protecting group, preventing an anthracene guest from undergoing Diels-Alder reaction. Under ultraviolet (UV) light, the pyridinium C?N bonds in TPZ3+ platforms are polarized and weakened, resulting in the occurrence of cage decomposition via ?-elimination. Guest recognition could help to prevent this UV-stimulated cage decomposition by suppressing the excitation of the TPZ3+ units.

SUBMITTER: Zhang C

PROVIDER: S-EPMC6957241 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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A mutually stabilized host-guest pair.

Zhang Chi C Wang Hongye H Zhong Jie J Lei Ye Y Du Renfeng R Zhang Yang Y Shen Libo L Jiao Tianyu T Zhu Yulu Y Zhu Haiming H Li Haoran H Li Hao H

Science advances 20191101 11

By using click chemistry, a hexacationic cage was synthesized. The cage contains two triscationic π-electron-deficient trispyridiniumtriazine (TPZ<sup>3+</sup>) platforms that are bridged in a face-to-face manner by three ethylene-triazole-ethylene linkers. A diversity of π-electron-rich guests can be recognized within the pocket of the cage, driven by host-guest π-π interactions. The cage cavity acts as a protecting group, preventing an anthracene guest from undergoing Diels-Alder reaction. Und ...[more]

PMID: 31976368

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