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Updated: Apr 27, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Helicity inversion and redox chemistry of chiral manganese(II) cubanes
Claire Deville1, Matteo Granelli, Alan M Downward
1Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai Ernest Ansermet, CH 1211 Geneva 4, Switzerland. Alan.Willliams@unige.ch.
Abstract:
The chiral ligand S-1,2-bis(1H-benzimidazol-2-yl)ethanol, 1, reacts with manganese(II) salts to form cubanes which readily undergo oxidation reactions leading either to a tetranuclear manganese(II,III) mixed valence complex 4 or to a tetranuclear complex of ligand 5 where the secondary alcohol has been oxidised to an enolate. N-methylation of ligand 1 slows the oxidation reaction and stable manganese(II) cubanes may be isolated. The fully methylated ligand 2 gives a cubane of opposite helicity to that found previously for 1 with cobalt. The inversion may be explained by conformational analysis. Cyclic voltammetry suggests that the manganese cubanes reported here are insufficiently robust to store oxidising equivalents as in the oxygen evolving system of photosystem II.
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