Details
| Original language | English |
|---|---|
| Pages (from-to) | 16187-16194 |
| Number of pages | 8 |
| Journal | Journal of Physical Chemistry |
| Volume | 100 |
| Issue number | 40 |
| Publication status | Published - 3 Oct 1996 |
| Externally published | Yes |
Abstract
Quantum chemical calculations of the proton-transfer system 2-(2′,4′-dinitrobenzyl)pyridine (DNBP) and of derivatives with larger aromatic bases are presented. These systems undergo photochemical isomerizations from a stable form to two different photoisomers. Ab initio methods are employed to investigate the isomerization of methylimine to vinylamine as a model system for the proton-transfer reaction of DNBP. The ground and excited states of both isomers and of the transition state for the isomerization are studied with Hartree-Fock and MRD-CI (multireference singles and doubles CI) methods. The isomerizations of the larger system DNBP and its derivatives are investigated with semiempirical PM3-SCF and PM3-MRD-CI methods. The intrinsic reaction coordinate formalism is used for calculating the reaction pathways from the optimized transition states. The relative stabilities of the various isomers and the mechanism of the intramolecular proton-transfer reaction are discussed. The ortho-nitro group assists the proton transfer from the methylene group to the pyridine ring. The experimentally observed reaction barriers are reproduced by taking crystal effects into account.
ASJC Scopus subject areas
- Engineering(all)
- General Engineering
- Chemistry(all)
- Physical and Theoretical Chemistry
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In: Journal of Physical Chemistry, Vol. 100, No. 40, 03.10.1996, p. 16187-16194.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Quantum chemical investigations of the thermal and photoinduced proton-transfer reactions of 2-(2′,4′-dinitrobenzyl)pyridine
AU - Frank, Irmgard
AU - Grimme, Stefan
AU - Peyerimhoff, Sigrid D.
PY - 1996/10/3
Y1 - 1996/10/3
N2 - Quantum chemical calculations of the proton-transfer system 2-(2′,4′-dinitrobenzyl)pyridine (DNBP) and of derivatives with larger aromatic bases are presented. These systems undergo photochemical isomerizations from a stable form to two different photoisomers. Ab initio methods are employed to investigate the isomerization of methylimine to vinylamine as a model system for the proton-transfer reaction of DNBP. The ground and excited states of both isomers and of the transition state for the isomerization are studied with Hartree-Fock and MRD-CI (multireference singles and doubles CI) methods. The isomerizations of the larger system DNBP and its derivatives are investigated with semiempirical PM3-SCF and PM3-MRD-CI methods. The intrinsic reaction coordinate formalism is used for calculating the reaction pathways from the optimized transition states. The relative stabilities of the various isomers and the mechanism of the intramolecular proton-transfer reaction are discussed. The ortho-nitro group assists the proton transfer from the methylene group to the pyridine ring. The experimentally observed reaction barriers are reproduced by taking crystal effects into account.
AB - Quantum chemical calculations of the proton-transfer system 2-(2′,4′-dinitrobenzyl)pyridine (DNBP) and of derivatives with larger aromatic bases are presented. These systems undergo photochemical isomerizations from a stable form to two different photoisomers. Ab initio methods are employed to investigate the isomerization of methylimine to vinylamine as a model system for the proton-transfer reaction of DNBP. The ground and excited states of both isomers and of the transition state for the isomerization are studied with Hartree-Fock and MRD-CI (multireference singles and doubles CI) methods. The isomerizations of the larger system DNBP and its derivatives are investigated with semiempirical PM3-SCF and PM3-MRD-CI methods. The intrinsic reaction coordinate formalism is used for calculating the reaction pathways from the optimized transition states. The relative stabilities of the various isomers and the mechanism of the intramolecular proton-transfer reaction are discussed. The ortho-nitro group assists the proton transfer from the methylene group to the pyridine ring. The experimentally observed reaction barriers are reproduced by taking crystal effects into account.
UR - http://www.scopus.com/inward/record.url?scp=0000873016&partnerID=8YFLogxK
U2 - 10.1021/jp960923+
DO - 10.1021/jp960923+
M3 - Article
AN - SCOPUS:0000873016
VL - 100
SP - 16187
EP - 16194
JO - Journal of Physical Chemistry
JF - Journal of Physical Chemistry
SN - 0022-3654
IS - 40
ER -