| Autor: |
Kua J; Department of Chemistry and Biochemistry, University of San Diego , 5998 Alcala Park, San Diego, California 92110, United States., Rodriguez AA, Marucci LA, Galloway MM, De Haan DO |
| Jazyk: |
angličtina |
| Zdroj: |
The journal of physical chemistry. A [J Phys Chem A] 2015 Mar 12; Vol. 119 (10), pp. 2122-31. Date of Electronic Publication: 2015 Feb 27. |
| DOI: |
10.1021/jp512396d |
| Abstrakt: |
Density functional theory calculations, including Poisson-Boltzmann implicit solvent and free energy corrections, are applied to construct a free energy map of formaldehyde and ammonia co-oligomerization in aqueous solution at pH 7. The stepwise route to forming hexamethylenetetramine (HMTA), the one clearly identified major product in a complex mixture, involves a series of addition reactions of formaldehyde and ammonia coupled with dehydration and cyclization reactions at key steps in the pathway. The free energy map also allows us to propose the possible identity of some major peaks observed by mass spectroscopy in the reaction mixture being the result of stable species not along the pathway to HMTA, in particular those formed by intramolecular condensation of hydroxyl groups to form six-membered rings with ether linkages. Our study complements a baseline free energy map previously worked out for the self-oligomerization of formaldehyde in solution at pH 7 using the same computational protocol and published in this journal (J. Phys. Chem. A 2013, 117, 12658). |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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