Electrochemistry of Cobalta Bis(dicarbollide) Ions Substituted at Carbon Atoms with Hydrophilic Alkylhydroxy and Carboxy Groups

0561301 - BFÚ 2023 RIV CH eng J - Článek v odborném periodiku
Fojt, Lukáš - Grüner, Bohumír - Nekvinda, Jan - Tüzün, Ece Zeynep - Havran, Luděk - Fojta, Miroslav
Electrochemistry of Cobalta Bis(dicarbollide) Ions Substituted at Carbon Atoms with Hydrophilic Alkylhydroxy and Carboxy Groups.
Molecules. Roč. 27, č. 6 (2022), č. článku 1761. E-ISSN 1420-3049
Grant CEP: GA ČR(CZ) GA19-04630S
Institucionální podpora: RVO:68081707 ; RVO:61388980
Klíčová slova: metallacarborane * cobalta bis(dicarbollide) ions * glassy carbon electrode * differential pulse voltammetry
Obor OECD: Inorganic and nuclear chemistry; Inorganic and nuclear chemistry (UACH-T)
Impakt faktor: 4.6, rok: 2022
Způsob publikování: Open access
https://www.mdpi.com/1420-3049/27/6/1761

In this study we explore the effect on the electrochemical signals in aqueous buffers of the presence of hydrophilic alkylhydroxy and carboxy groups on the carbon atoms of cobalta bis(dicarbollide) ions. The oxygen-containing exo-skeletal substituents of cobalta bis(dicarbollide) ions belong to the perspective building blocks that are considered for bioconjugation. Carbon substitution provides wider versatility and applicability in terms of the flexibility of possible chemical pathways. However, until recently, the electrochemistry of compounds substituted only on boron atoms could be studied, due to the unavailability of carbon-substituted congeners. In the present study, electrochemistry in aqueous phosphate buffers is considered along with the dependence of electrochemical response on pH and concentration. The compounds used show electrochemical signals around1.3 and +1.1 V of similar or slightly higher intensities than in the parent cobalta bis(dicarbollide) ion. The signals at positive electrochemical potential correspond to irreversible oxidation of the boron cage (the C2B9 building block) and at negative potential correspond to the reversible redox process of (CoIII/CoII) at the central atom. Although the first signal is typically sharp and its potential can be altered by a number of substituents, the second signal is complex and is composed of three overlapping peaks. This signal shows sigmoidal character at higher concentrations and may be used as a diagnostic tool for aggregation in solution. Surprisingly enough, the observed effects of the site of substitution (boron or carbon) and between individual groups on the electrochemical response were insignificant. Therefore, the substitutions would preserve promising properties of the parent cage for redox labelling, but would not allow for the further tuning of signal position in the electrochemical window.
Trvalý link: https://hdl.handle.net/11104/0333991