AI Article Synopsis
- N-alkoxyheterocycles serve as effective one-electron acceptors in photochemical reactions, generating radicals that can break down into alkoxy radicals and neutral heterocycles.
- The study measures the kinetics of the N-O bond fragmentation reaction across different radicals, revealing a vast range of rate constants differing by seven orders of magnitude.
- Researchers explain the variation in reaction rates through the relationship between the energies of relevant molecular orbitals and a specific reaction potential energy surface, supported by advanced electronic structure calculations.
Article Abstract
N-alkoxyheterocycles can act as powerful one-electron acceptors in photochemical electron-transfer reactions. One-electron reduction of these species results in formation of a radical that undergoes N-O bond fragmentation to form an alkoxy radical and a neutral heterocycle. The kinetics of this N-O bond fragmentation reaction have been determined for a series of radicals with varying substituents and extents of delocalization. Rate constants varying over 7 orders of magnitude are obtained. A reaction potential energy surface is described that involves avoidance of a conical intersection. A molecular basis for the variation of the reaction rate constant with radical structure is given in terms of the relationship between the energies of the important molecular orbitals and the reaction potential energy surface. Ab initio and density functional electronic structure calculations provide support for the proposed reaction energy surface.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/ja020768e | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Synthetically Reversible, Proton-Mediated Nitrite N-O Bond Cleavage at a Dicopper Site.
J Am Chem Soc
December 2024
Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States.
A monocationic dicopper(I,I) nitrite complex [Cu(μ-κ:κ-ON)DPFN][NTf] () (DPFN = 2,7-bis(fluoro-di(2-pyridyl)methyl)-1,8-naphthyridine, NTf = N(SOCF)), was synthesized by treatment of a dicopper acetonitrile complex, [Cu(μ-MeCN)DPFN][NTf] (), with tetrabutylammonium nitrite ([BuN][NO]). DFT calculations indicate that is one of three linkage isomers that are close in energy and presumably accessible in solution. Reaction of the μ-κ:κ-ON complex with -TolSH produces nitrous acid (HONO) and the corresponding dicopper thiolate species via an acid-base exchange reaction.
View Article and Find Full Text PDFA nonequilibrium kinetic model of high-resolution vibrational energy transfer in RDX from selective IR excitation.
J Chem Phys
December 2024
Center for Engineering Concepts Development, Department of Mechanical Engineering, University of Maryland at College Park, College Park, Maryland 20742, USA.
In this paper, we develop a model based on a second quantization-with anharmonic phonon scattering and the phonon Boltzmann transport equation-to study precise high-resolution nonequilibrium vibrational energy transfer (VET) under selective phonon excitation in cyclotrimethylene trinitramine. We simulate mid-infrared pump-probe spectroscopy and observe a prompt appearance (<1 ps) of broad-spectrum intensity, which agrees well with experimental data in the literature. The selective excitation of phonons at different frequencies reveals distinct VET pathways and the kinetic evolution of mode occupations as the system reaches a new equilibrium temperature.
View Article and Find Full Text PDFDevelopment of a Triazinyluronium-Based Dehydrative Condensing Reagent with No Heteroatomic Bonds.
J Org Chem
December 2024
Faculty of Pharmaceutical Sciences, Institute of Medical, Pharmaceutical, and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Article Synopsis
- A new dehydrative condensing reagent, DMT-TU, has been created, which is based on triazinyluronium.
- DMT-TU is safer than traditional reagents since it lacks high-energy N-N and N-O bonds, making it less explosive according to differential scanning calorimetry.
- The reagent successfully converts carboxylic acids and amines into amides at room temperature and minimizes racemization in peptide bond formation.
Refining Metal-Free Carbon Nanoreactors through Electronic and Geometric Comodification for Boosted HO Electrosynthesis toward Efficient Water Decontamination.
Environ Sci Technol
December 2024
College of Energy, Soochow Institute for Energy and Materials Innovations, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China.
Hydrogen peroxide (HO) electrosynthesis using metal-free carbon materials via the 2e oxygen reduction pathway has sparked considerable research interest. However, the scalable preparation of carbon electrocatalysts to achieve satisfactory HO yield in acidic media remains a grand challenge. Here, we present the design of a carbon nanoreactor series that integrates precise O/N codoping alongside well-regulated geometric structures targeting high-efficiency electrosynthesis of HO.
View Article and Find Full Text PDF-Hydroxyphthalimides as Nitrogen Radical Precursors in the Copper-Catalyzed Radical Cross-Coupling Amination of Arylboronic Acids: Synthesis of Arylamines.
J Org Chem
December 2024
College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
Article Synopsis
- A new method for synthesizing arylamines has been introduced, utilizing copper as a catalyst for radical cross-coupling amination with arylboronic acids.
- This innovative approach involves using -hydroxyphthalimides to create nitrogen-based radicals, which effectively react with arylboronic acids, achieving yields of up to 98%.
- The process shows excellent efficiency with various functional groups, and studies indicate that a nitrogen radical cross-coupling mechanism is facilitated by the breaking of N-O bonds using phosphites.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!