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Electronic fluxes during diels-alder reactions involving 1,2-benzoquinones: mechanistic insights from the analysis of electron localization function and catastrophe theory†
Article first published online: 2 AUG 2012
Copyright © 2012 Wiley Periodicals, Inc.
Journal of Computational Chemistry
Volume 33, Issue 30, pages 2400–2411, 15 November 2012
How to Cite
González-Navarrete, P., Domingo, L. R., Andrés, J., Berski, S. and Silvi, B. (2012), Electronic fluxes during diels-alder reactions involving 1,2-benzoquinones: mechanistic insights from the analysis of electron localization function and catastrophe theory. J. Comput. Chem., 33: 2400–2411. doi: 10.1002/jcc.23085
- Issue published online: 13 OCT 2012
- Article first published online: 2 AUG 2012
- Manuscript Accepted: 10 JUL 2012
- Manuscript Revised: 2 JUL 2012
- Manuscript Received: 15 MAY 2012
- Generalitat Valenciana. Grant Number: Prometeo/2009/053
- Spanish Ministry Ministerio de Ciencia e Innovación. Grant Numbers: CTQ2009-14541-C02, CTQ2009-11027/BQU
- Fundación Bancaja. Grant Number: P1.1B2010-10
- Universitat Jaume (the Postdoctoral grant)
- Fundación Bancaixa-UJI (financial support during research stays at UJI, 2010 and 2011)
- electron localization function;
- catastrophe theory;
- Diels-Alder reactions;
By means of the joint use of electron localization function (ELF) and Thom's catastrophe theory, a theoretical analysis of the energy profile for the hetero-Diels-Alder reaction of 4-methoxy-1,2-benzoquinone 1 and methoxyethylene 2 has been carried out. The 12 different structural stability domains obtained by the bonding evolution theory have been identified as well as the bifurcation catastrophes (fold and cusp) responsible for the changes in the topology of the system. This analysis permits finding a relationship between the ELF topology and the evolution of the bond breaking/forming processes and electron pair rearrangements through the reaction progress in terms of the different ways of pairing up the electrons. The reaction mechanism corresponds to an asynchronous electronic flux; first, the O1C5 bond is formed by the nucleophilic attack of the C5 carbon of the electron rich ethylene 2 on the most electrophilically activated carbonyl O1 oxygen of 1, and once the σ bond has been completed, the formation process of the second O4C6 bond takes place. In addition, the values of the local electrophilicity and local nucleophilcity indices in the framework of conceptual density functional theory accounts for the asychronicity of the process as well as for the observed regioselectivity. © 2012 Wiley Periodicals, Inc.