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Updated: May 1, 2026
Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Distortional supramolecular isomers of polyrotaxane coordination polymers: photoreactivity and sensing of nitro
In-Hyeok Park1, Raghavender Medishetty, Ja-Yeon Kim
1Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University, Jinju 660-701 (South Korea).
Abstract:
Distortional isomers, or bond-stretch isomers, differ only in the length of one or more bonds, which is due to crystallographic disorder in most cases. The term distortional isomerism is introduced to describe the structures of polyrotaxane 2D coordination polymers (CPs) that differ only by the relative positions in the neighboring entangled axles. A large ring and a long spacer ligand in 2D CPs yielded four different supramolecular isomers, of which two have an entangled polyrotaxane structure. One pair of C=C bonds in the spacer ligand is well-aligned in one isomer and undergoes [2+2] cycloaddition reaction, whereas the other isomer is photoinert. They also have different sensing efficiency for several aromatic nitro compounds. However, both isomers show selective PL quenching for the Brady's reagent. Structurally similar supramolecular isomers with different photochemical reactivity and sensing abilities appear to be unprecedented.
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