Item


An analysis of the isomerization energies of 1,2-/1,3-diazacyclobutadiene, pyrazole/imidazole, and pyridazine/pyrimidine with the turn-upside-down approach

The isomerization energies of 1,2- and 1,3-diazacyclobutadiene, pyrazole and imidazole, and pyridazine and pyrimidine are 10.6, 9.4, and 20.9 kcal/mol, respectively, at the BP86/TZ2P level of theory. These energies are analyzed using a Morokuma-like energy decomposition analysis in conjunction with what we have called turn-upside-down approach. Our results indicate that, in the three cases, the higher stability of the 1,3-isomers is not due to lower Pauli repulsions but because of the more favorable σ-orbital interactions involved in the formation of two C-N bonds in comparison with the generation of C-C and N-N bonds in the 1,2-isomers

We thank the following organizations for financial support: the Ministerio de Ciencia e Innovacion (MICINN, Project Nos. CTQ2008-03077/BQU, CTQ2008-06532/BQU, and CTQ2011-23156/BQU, Ramon y Cajal contract to J.P., and FPI fellowship to M.E.H.) and the DIUE of the Generalitat de Catalunya (project no. 2009SGR637). W.T. thanks FONDECYT (Grant No. 1109043). We acknowledge helpful comments from Prof. Dr. F. Matthias Bickelhaupt. Excellent service by the Centre de Supercomputacio de Catalunya (CESCA) is gratefully acknowledged

American Chemical Society (ACS)

Manager: Ministerio de Educación y Ciencia (Espanya)
Ministerio de Ciencia e Innovación (Espanya)
Generalitat de Catalunya. Agència de Gestió d’Ajuts Universitaris i de Recerca
Author: El Hamdi Lahfid, Majid
Tiznado, William
Poater i Teixidor, Jordi
Solà i Puig, Miquel
Abstract: The isomerization energies of 1,2- and 1,3-diazacyclobutadiene, pyrazole and imidazole, and pyridazine and pyrimidine are 10.6, 9.4, and 20.9 kcal/mol, respectively, at the BP86/TZ2P level of theory. These energies are analyzed using a Morokuma-like energy decomposition analysis in conjunction with what we have called turn-upside-down approach. Our results indicate that, in the three cases, the higher stability of the 1,3-isomers is not due to lower Pauli repulsions but because of the more favorable σ-orbital interactions involved in the formation of two C-N bonds in comparison with the generation of C-C and N-N bonds in the 1,2-isomers
We thank the following organizations for financial support: the Ministerio de Ciencia e Innovacion (MICINN, Project Nos. CTQ2008-03077/BQU, CTQ2008-06532/BQU, and CTQ2011-23156/BQU, Ramon y Cajal contract to J.P., and FPI fellowship to M.E.H.) and the DIUE of the Generalitat de Catalunya (project no. 2009SGR637). W.T. thanks FONDECYT (Grant No. 1109043). We acknowledge helpful comments from Prof. Dr. F. Matthias Bickelhaupt. Excellent service by the Centre de Supercomputacio de Catalunya (CESCA) is gratefully acknowledged
Format: application/pdf
Document access: http://hdl.handle.net/10256/11390
Language: eng
Publisher: American Chemical Society (ACS)
Collection: info:eu-repo/semantics/altIdentifier/doi/10.1021/jo201639k
info:eu-repo/semantics/altIdentifier/issn/0022-3263
info:eu-repo/semantics/altIdentifier/eissn/1520-6904
info:eu-repo/grantAgreement/MICINN//CTQ2008-03077/ES/CLUSTERES METALICOS Y SEMIMETALICOS. ESTUDIOS DE AROMATICIDAD Y REACTIVIDAD/
info:eu-repo/grantAgreement/MICINN//CTQ2008-06532/ES/REACTIVIDAD Y ENLACE QUIMICO EN BIOMEDICINA Y QUIMICA (BIO)INORGANICA/
info:eu-repo/grantAgreement/MICINN//CTQ2011-23156/ES/AVANCES EN CATALISIS Y AROMATICIDAD/
AGAUR/2009-2014/2009 SGR-637
Rights: Tots els drets reservats
Subject: Isomerització
Isomerization
Title: An analysis of the isomerization energies of 1,2-/1,3-diazacyclobutadiene, pyrazole/imidazole, and pyridazine/pyrimidine with the turn-upside-down approach
Type: info:eu-repo/semantics/article
Repository: DUGiDocs

Subjects

Authors