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Ferrocene donor linked to pyridine/pyridinium acceptor via a systematically enlarged π-linker.

ABSTRACT: Nine chromophores with ferrocene donor and pyridine/pyridinium acceptors have been prepared and further investigated. The performed X-ray analysis showed partially polarized and geometrically oblate pyridine unit. An extension of the π-system and N-quaternization were revealed as suitable tools for exclusive manipulation of the LUMO with the almost steady HOMO. Whereas the electrochemical HOMO-LUMO gap can be tuned from 3.01 to 1.49 eV, the high- and low-energy absorption bands were found within the range of 280-402/456-547 nm. The pyridinium chromophores showed distinct negative solvatochromism. A thorough DFT analysis has been performed; it turned out that ferrocene donor is capable of two principal D-A interactions, whose employment depends on the appended electron-withdrawing moiety.

SUBMITTER: Kulhanek J

PROVIDER: S-EPMC9044170 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Ferrocene donor linked to pyridine/pyridinium acceptor via a systematically enlarged π-linker.

Kulhánek Jiří J Klikar Milan M Pytela Oldřich O Růžičková Zdenka Z Bureš Filip F

RSC advances 20211101 61

Nine chromophores with ferrocene donor and pyridine/pyridinium acceptors have been prepared and further investigated. The performed X-ray analysis showed partially polarized and geometrically oblate pyridine unit. An extension of the π-system and N-quaternization were revealed as suitable tools for exclusive manipulation of the LUMO with the almost steady HOMO. Whereas the electrochemical HOMO-LUMO gap can be tuned from 3.01 to 1.49 eV, the high- and low-energy absorption bands were found ...[more]

PMID: 35493213

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