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

Al-Yassiri MA, Puchta R (2023)

Publication Type: Journal article

Publication year: 2023

Journal

ChemPhysChem Wiley

DOI: 10.1002/cphc.202200688

Abstract

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 ∇2ρ(r), (2D-3D) multidimensional off-nucleus magnetic shielding (σzz(r) and σiso(r)), and scanning nucleus-independent chemical shift (NICSzz 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 σzz(r) and σiso(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.

Authors with CRIS profile

Ralph Puchta Lehrstuhl für Anorganische und Metallorganische Chemie

Involved external institutions

University of Baghdad IQ Iraq (IQ)

How to cite

APA:

Al-Yassiri, M.A., & Puchta, R. (2023). Predicting a New Δ-Proton Sponge-Base of 4,12-Dihydrogen-4,8,12-triazatriangulene through Proton Affinity, Aromatic Stabilization Energy, and Aromatic Magnetism. ChemPhysChem. https://dx.doi.org/10.1002/cphc.202200688

MLA:

Al-Yassiri, Muntadar A.H., and Ralph Puchta. "Predicting a New Δ-Proton Sponge-Base of 4,12-Dihydrogen-4,8,12-triazatriangulene through Proton Affinity, Aromatic Stabilization Energy, and Aromatic Magnetism." ChemPhysChem (2023).

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