Chlorination of ammonia and aliphatic amines by Cl2: DFT study of medium and substituent effects
| Autor: | Hrvoje Meštrić, Valerije Vrček |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
inorganic chemicals
Reaction mechanism Electronic correlation Chemistry Organic Chemistry Substituent Photochemistry Solvent chemistry.chemical_compound quantum chemical calculation chlorination aliphatic amines reaction mechanism solvent effect substituent effect Computational chemistry Potential energy surface Molecule Amine gas treating Physical and Theoretical Chemistry Solvent effects |
| Zdroj: | Journal of Physical Organic Chemistry. 22:59-68 |
| ISSN: | 1099-1395 0894-3230 |
| Popis: | The mechanism of chlorination of ammonia and aliphatic amines by Cl2 was studied by quantum-chemical calculations using a series of DFT functionals. Three different reaction pathways were considered for the reaction between Cl2 and NH3 in the gas phase. Several intermediates and transition state structures, not described earlier, were located on the corresponding potential energy surface. It is calculated that the reaction field effects (SCIPCM) on the chlorination is much less pronounced than the effect of a specific solvent interaction which was modeled by an explicit water molecule. It is also found that the calculated energy barrier and the reaction free energy of the chlorination of different amines are dependent on the alkyl-substituent effects. With increase in the basicity of amine, the chlorination reaction becomes more feasible. Calculated geometries of intermediates and overall reaction energetics are significantly influenced by the method for a treatment of electron correlation (DFT vs. MP2), and by the fraction of HF exchange (χ) in DFT functionals. With increase in the χ in the corresponding functional, the DFT results approach those obtained at the MP2 level, and are closer to experimental values, as well. Copyright © 2008 John Wiley & Sons, Ltd. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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