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Zinc-[7]helicenocyanine and Its Discrete π-Stacked Homochiral Dimer.

ABSTRACT: In this communication, we demonstrate a novel approach to prepare a discrete dimer of chiral phthalocyanine (Pc) by exploiting the flexible molecular geometry of helicenes, which enables structural interlocking and strong aggregation tendency of Pcs. Synthesized [7]helicene-Pc hybrid molecular structure, zinc-[7]helicenocyanine (Zn-7HPc), exclusively forms a stable dimeric pair consisting of two homochiral molecules. The dimerization constants were estimated to be as high as 8.96×10⁶ M^-1 and 3.42×10⁷ M^-1 in THF and DMSO, respectively, indicating remarkable stability of dimer. In addition, Zn-7HPc exhibited chiral self-sorting behavior, which resulted in preferential formation of a homochiral dimer also in the racemic sample. Two phthalocyanine subunits in the dimeric form strongly communicate with each other as revealed by a large comproportionation constant and observation of an IV-CT band for the thermodynamically stable mixed-valence state.

SUBMITTER: Zhang F

PROVIDER: S-EPMC8597050 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Zinc-[7]helicenocyanine and Its Discrete π-Stacked Homochiral Dimer.

Zhang Fangyuan F Radacki Krzysztof K Braunschweig Holger H Lambert Christoph C Ravat Prince P

Angewandte Chemie (International ed. in English) 20210928 44

In this communication, we demonstrate a novel approach to prepare a discrete dimer of chiral phthalocyanine (Pc) by exploiting the flexible molecular geometry of helicenes, which enables structural interlocking and strong aggregation tendency of Pcs. Synthesized [7]helicene-Pc hybrid molecular structure, zinc-[7]helicenocyanine (Zn-7HPc), exclusively forms a stable dimeric pair consisting of two homochiral molecules. The dimerization constants were estimated to be as high as 8.96×10<sup>6</sup> ...[more]

PMID: 34403564

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