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The oxidation state in low-valent beryllium and magnesium compounds.

ABSTRACT: Low-valent group 2 (E = Be and Mg) stabilized compounds have been long synthetically pursued. Here we discuss the electronic structure of a series of Lewis base-stabilized Be and Mg compounds. Despite the accepted zero(0) oxidation state nature of the group 2 elements of some recent experimentally accomplished species, the analysis of multireference wavefunctions provides compelling evidence for a strong diradical character with an oxidation state of +2. Thus, we elaborate on the distinction between a description as a donor-acceptor interaction L(0) ⇆ E(0) ⇄ L(0) and the internally oxidized situation, better interpreted as a diradical L(-1) → E(+2) ← L(-1) species. The experimentally accomplished examples rely on the strengthened bonds by increasing the π-acidity of the ligand; avoiding this interaction could lead to an unprecedented low-oxidation state.

SUBMITTER: Gimferrer M

PROVIDER: S-EPMC9172369 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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The oxidation state in low-valent beryllium and magnesium compounds.

Gimferrer Martí M Danés Sergi S Vos Eva E Yildiz Cem B CB Corral Inés I Jana Anukul A Salvador Pedro P Andrada Diego M DM

Chemical science 20220509 22

Low-valent group 2 (E = Be and Mg) stabilized compounds have been long synthetically pursued. Here we discuss the electronic structure of a series of Lewis base-stabilized Be and Mg compounds. Despite the accepted zero(0) oxidation state nature of the group 2 elements of some recent experimentally accomplished species, the analysis of multireference wavefunctions provides compelling evidence for a strong diradical character with an oxidation state of +2. Thus, we elaborate on the distinction bet ...[more]

PMID: 35756523

Similar Datasets

Comment on "The oxidation state in low-valent beryllium and magnesium compounds" by M. Gimferrer, S. Danes, E. Vos, C. B. Yildiz, I. Corral, A. Jana, P. Salvador and D. M. Andrada, <i>Chem. Sci.</i> 2022, <b>13</b>, 6583.

Project description:We challenge the assignment of the oxidation state +2 for beryllium and magnesium in the complexes Be(cAACDip)2 and Mg(cAACDip)2 as suggested by Gimferrer et al., Chem. Sci. 2022, 13, 6583 in a recent study. A careful review of the data in the ESI contradicts their own statement and shows that the results support the earlier suggestion that the metals are in the zero oxidation state. The authors reported wrong data for the excitation energies of Be and Mg to the 1D (np2) state. We also correct some misleading statements about the EDA method.

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Polyoxometalate-enhanced oxidation of organic compounds by nanoparticulate zero-valent iron and ferrous ion in the presence of oxygen.

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