Inherently chiral monomers with biindole cores and oligothiophene terminals: redox site interactions, electrooligomerization and enantiodiscrimination ability in electrochemistry

Inherently chiral monomers with biindole cores and oligothiophene terminals: redox site interactions, electrooligomerization and enantiodiscrimination ability in electrochemistry Elisa Emanuele*a,#,Tiziana Benincorib, Andrea Penonib, Luca Scapinellob, Giorgia Bonettib, Serena Arnaboldia, Sara Grecchia, Patrizia R. Mussinia, Roberto Cirillic, Jiří Ludvíkd, Magdaléna Hromadovád a Dip. di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano (Italy); bUniv. degli Studi dell'Insubria, Dip. di Scienza e Alta Tecnologia, Via Valleggio 11, 22100 Como (Italy) c Centro Nazionale per il Controllo e la Valutazione dei Farmaci, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Roma (Italy) d Dept. of Molecular Electrochemistry and Catalysis, J. Heyrovsky Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8 (Czech Republic) *[email protected], #present address: Dept. of Energy, Politecnico di Milano, via Lambruschini 4, 20156 Milano, Italy Inherently chiral monomers based on biindole atropisomeric cores and thiophene-terminated wings can be regarded as a fascinating family of electrochemically active objects. They provide a nice casebook for studies of equivalent redox sites interacting through a torsional barrier modulable through molecular design. Moreover, configurationally stable family terms can be separated into enantiomers and electrooligomerized yielding chirally modified electrodes with outstanding performances in chiral voltammetry and magnetoelectrochemistry experiments. A minireview of the so far developed family [1-5] will be presented, discussing the modulating effects on the monomer functional properties of (a) the biindole core connectivity, (b) the (hetero)aromatic wings structure and length and, most importantly, (c) the substituents on the N sites of the biindole core, a key tool for enhancing enantiodiscrimination by providing additional coordination elements. References [1] S. Arnaboldi, T. Benincori, A. Penoni, L. Vaghi, R. Cirilli, S. Abbate, G. Longhi, G. Mazzeo, S. Grecchi, M. Panigati, P. R. Mussini, Chem. Science 2019, 10, 2708. [2] C. Malacrida, L. Scapinello, R. Cirilli, S. Grecchi, A. Penoni, T. Benincori, S. Ludwigs, ChemElectroChem 2021, 8, 3250. [3] L. Scapinello, S. Grecchi, S. Rossi, F. Arduini, S. Arnaboldi, A. Penoni, R. Cirilli, P.R. Mussini, T. Benincori, Chem. Eur. J. 2021, 27, 13190. [4] S. Arnaboldi, S. Grecchi, L. Vaghi, A. Penoni, L. Scapinello, I.F. Buzzi, R. Cirilli, M. Pierini, T. Benincori, P.R.Mussini, ChemElectroChem 2022, 9, e202100903. [5] S. Grecchi, G. Bonetti, E. Emanuele, J. Ludvík, L. Koláčná, A. Liška, M. Hromadová, S. Arnaboldi, R. Cirilli, P.R. Mussini, T. Benincori, Chem. Eur. J. 2024, 23, e202303530.