Predicting a New Δ-Proton Sponge-Base of 4,12-Dihydrogen-4,8,12-triazatriangulene through Proton Affinity, Aromatic Stabilization Energy, and Aromatic Magnetism.

Autor: Al-Yassiri MAH; Department of Chemistry - College of Science, University of Baghdad, Al-Jadirya, Baghdad, Iraq., Puchta R; Inorganic Chemistry, Department of Chemistry and Pharmacy, University of Erlangen - Nuremberg, Egerlandstr. 1, 91058, Erlangen, Germany.; Computer Chemistry Center, Department of Chemistry and Pharmacy, University of Erlangen - Nuremberg, Nägelsbachstr. 25, 91052, Erlangen, Germany.; Central Institute for Scientific Computing (ZISC), University of Erlangen - Nuremberg, Martensstr. 5a, 91058, Erlangen, Germany.; Fakultät Angewandte Mathematik, Physik und Allgemeinwissenschaften, Technische Hochschule Nürnberg Georg Simon Ohm, Keßlerplatz 12, 90489, Nürnberg, Germany.
Jazyk: angličtina
Zdroj: Chemphyschem : a European journal of chemical physics and physical chemistry [Chemphyschem] 2023 Aug 15; Vol. 24 (16), pp. e202200688. Date of Electronic Publication: 2023 Jun 27.
DOI: 10.1002/cphc.202200688
Abstrakt: Herein, we report designing a new Δ (delta-shaped) proton sponge base of 4,12-dihydrogen-4,8,12-triazatriangulene (compound 1) and calculating its proton affinity (PA), aromatic stabilization, natural bond orbital (NBO), electron density ρ(r), Laplacian of electron density ∇ 2 ρ(r), (2D-3D) multidimensional off-nucleus magnetic shielding (σ zz (r) and σ iso (r)), and scanning nucleus-independent chemical shift (NICS zz and NICS). Density functional theory (DFT) at B3LYP/6-311+G(d,p), ωB97XD/6-311+G(d,p), and PW91/def2TZVP were used to compute the magnetic shielding variables. In addition, relevant bases like pyridine, quinoline, and acridine were also studied and compared. The protonation of compound 1 yields a highly symmetric carbocation of three Hückel benzenic rings. Comparing our findings of the studied molecules showed that compound 1 precedes others in PA, aromatic isomerization stabilization energy, and basicity. Therefore, the basicity may be enhanced when a conjugate acid gains higher aromatic features than its unprotonated base. Both multidimensional σ zz (r) and σ iso (r) off-nucleus magnetic shieldings outperformed electron-based techniques and can visually monitor changes in aromaticity that occur by protonation. The B3LYP/6-311+G(d,p), ωB97XD/6-311+G(d,p), and PW91/def2TZVP levels showed no significant differences in detailing isochemical shielding surfaces.
(© 2023 The Authors. ChemPhysChem published by Wiley-VCH GmbH.)
Databáze: MEDLINE
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