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Rational synthesis of benzimidazole[3]arenes by Cu^II-catalyzed post-macrocyclization transformation.

ABSTRACT: A new series of calix[n]arene analogues, benzimidazole[3]arenes, was rationally synthesized by Cu^II-catalyzed post-macrocyclization transformation of a tris(o-phenylenediamine) macrocycle, and fully characterized by NMR, MS, and single-crystal X-ray diffraction (XRD) analyses. The resulting syn- and anti-benzimidazole[3]arenes have a bowl-shaped and a warped structure, respectively, in their crystalline states, and both display a dynamic inversion behavior in solution. This modification resulted in strong fluorescence due to the generated benzimidazole moieties. The mechanistic study of the post-macrocyclization transformation demonstrated that the formation of both benzimidazole[3]arenes was catalyzed, via triimine intermediates, by Cu^II ions in air through oxidation and cyclization of the tris(o-phenylenediamine) macrocycle.

SUBMITTER: Tashiro S

PROVIDER: S-EPMC6187690 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Rational synthesis of benzimidazole[3]arenes by CuII-catalyzed post-macrocyclization transformation.

Tashiro Shohei S Umeki Tsutomu T Kubota Ryou R Shionoya Mitsuhiko M

Chemical science 20180905 39

A new series of calix[n]arene analogues, benzimidazole[3]arenes, was rationally synthesized by CuII-catalyzed post-macrocyclization transformation of a tris(o-phenylenediamine) macrocycle, and fully characterized by NMR, MS, and single-crystal X-ray diffraction (XRD) analyses. The resulting syn- and anti-benzimidazole[3]arenes have a bowl-shaped and a warped structure, respectively, in their crystalline states, and both display a dynamic inversion behavior ...[more]

PMID: 30393521

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