| Autor: |
Dutta SS; School of Chemical Sciences, National Institute of Science Education and Research (NISER) Bhubaneswar, An OCC of Homi Bhabha National Institute, P.O. Jatni, Khurda, Odisha 752050, India., Lourderaj U; School of Chemical Sciences, National Institute of Science Education and Research (NISER) Bhubaneswar, An OCC of Homi Bhabha National Institute, P.O. Jatni, Khurda, Odisha 752050, India. |
| Jazyk: |
angličtina |
| Zdroj: |
The journal of physical chemistry. A [J Phys Chem A] 2024 Nov 19. Date of Electronic Publication: 2024 Nov 19. |
| DOI: |
10.1021/acs.jpca.4c06805 |
| Abstrakt: |
The mechanisms and dynamics of bimolecular nucleophilic substitution (S N 2) reactions are complex and influenced by the nature of the central atom. In this study, we explore S N 2 at a nitrogen center (S N 2@N) by investigating the reaction of chloramine (NH 2 Cl) with methoxide ion (CH 3 O - ) using ab initio classical trajectory simulations at the MP2(fc)/aug-cc-pVDZ level of theory. We observe that, in addition to the expected S N 2 product formation (CH 3 ONH 2 + Cl - ), a high-energy proton-transfer pathway leading to CH 3 OH and NHCl - dominates, with near-quantitative agreement between simulations and experimental data. Notably, we identify a novel hydride-transfer pathway yielding NH 3 , H 2 CO, and Cl - , revealing alternative reactivity channels previously uncharacterized in nitrogen-centered S N 2 reactions. Mechanistic analysis uncovers unconventional roaming-mediated and roundabout pathways alongside the traditional direct rebound and indirect mechanisms. Additionally, an umbrella inversion of the NH 2 group resulting in retention of configuration in the CH 3 ONH 2 product was observed in a fraction of trajectories. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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