Reactivity Indices related to DFT Theory, the Electron Localization Function (ELF) and Non-Covalent Interactions (NCI) Calculations in the Formation of the non-Halogenated Pyruvic Esters in Solution

The non-halogenated pyruvic esters are essential compounds, considering that they exhibit particular properties, due to the proximity of two functional groups: carbonyl and ester. These molecules can be obtained from the approach of the Lewis acid MgI2 on the iodinated pyruvic ester by using sodium hydrogen sulfite in aqueous solution, which selectively reduces the carbon-iodine bond of the iodinated pyruvic ester. The sites of attack of hydrogen sulfite of this reaction remained uncertain and were the subject of a debate between the experimenters. Our aim in this work is to determine the more favorable sites of attack by using the local indices (Parr functions). To approve the structure of the reagents, we have conducted a topological analysis of electron localization function (ELF). To reveal the type of interaction in the "ester pyruvic-hydrogen sulfite" complex, we have performed a non-covalent interactions (NCI) calculation. The analysis of local indices and NCI analysis of electron density indicate that the approach of the hydrogen sulfite ion will take place on the iodine atom elucidating the preferable site of the attack.

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Testing the tools for revealing and characterizing the iodine–iodine halogen bond in crystals

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520617002931 ◽

2017 ◽

Vol 73 (2) ◽

pp. 217-226 ◽

Cited By ~ 17

Author(s):

Ekaterina Bartashevich ◽

Irina Yushina ◽

Kristina Kropotina ◽

Svetlana Muhitdinova ◽

Vladimir Tsirelson

Keyword(s):

Electron Density ◽

Halogen Bond ◽

Electron Shell ◽

Electron Localization Function ◽

Electron Localization ◽

Localization Function ◽

Non Covalent Interactions ◽

The One ◽

Covalent Interactions

To understand what tools are really suitable to identify and classify the iodine–iodine non-covalent interactions in solid organic polyiodides, we have examined the anisotropy of the electron density within the iodine atomic basin along and across the iodine–iodine halogen bond using the Laplacian of electron density, one-electron potential and electron localization function produced by Kohn–Sham calculations with periodic boundary conditions. The Laplacian of electron density exhibits the smallest anisotropy and yields a vague picture of the outermost electronic shells. The one-electron potential does not show such a deficiency and reveals that the valence electron shell for the halogen-bond acceptor iodine is always wider than that for the halogen-bond donor iodine along its σ-hole direction. We have concluded that the one-electron potential is the most suitable for classification of the iodine–iodine bonds and interactions in complicated cases, while the electron localization function allows to distinguish the diiodine molecule bonded with the monoiodide anion from the typical triiodide anion.

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