TY - JOUR
T1 - The Mysticism of Pericyclic Reactions
T2 - A Contemporary Rationalisation of Organic Reactivity Based on Electron Density Analysis
AU - Domingo, Luis R.
AU - Ríos-Gutiérrez, Mar
AU - Silvi, Bernard
AU - Pérez, Patricia
N1 - Funding Information:
This research was supported by the Ministry of Economy and Competitiveness (MINECO) of the Spanish Government (project CTQ2016-78669-P, AEI/FEDER, UE) and Fondecyt, Chile (grant 1140341). M.R.-G. also thanks MINECO for a pre-doctoral contract, co-financed by the European Social Fund (BES-2014-068258).
PY - 2018/3/7
Y1 - 2018/3/7
N2 - The molecular mechanism of the five most representative “pericyclic reactions” has been studied by applying molecular electron density theory (MEDT). The different phases into which the reaction paths are topologically divided can be regrouped into four well-characterised steps: 1) the rupture of the C–C double bonds, 2) the formation of pseudoradical centres at the interacting carbons, 3) the formation of new C–C single bonds and 4) the formation of new C–C double bonds in the final products. Consequently, the bonding changes in these reactions are neither concerted nor cyclic. As the transition-state structures are located at the end of the large first group of phases or in the narrow second group, the high activation enthalpies found in these reactions are mainly associated with the rupture of C–C double bonds. The present MEDT study makes it possible to rule out the definition of “pericyclic reactions”, made by Woodward and Hoffmann in 1969, in which “all first order changes in bonding relationships take place in concert on a closed curve”.
AB - The molecular mechanism of the five most representative “pericyclic reactions” has been studied by applying molecular electron density theory (MEDT). The different phases into which the reaction paths are topologically divided can be regrouped into four well-characterised steps: 1) the rupture of the C–C double bonds, 2) the formation of pseudoradical centres at the interacting carbons, 3) the formation of new C–C single bonds and 4) the formation of new C–C double bonds in the final products. Consequently, the bonding changes in these reactions are neither concerted nor cyclic. As the transition-state structures are located at the end of the large first group of phases or in the narrow second group, the high activation enthalpies found in these reactions are mainly associated with the rupture of C–C double bonds. The present MEDT study makes it possible to rule out the definition of “pericyclic reactions”, made by Woodward and Hoffmann in 1969, in which “all first order changes in bonding relationships take place in concert on a closed curve”.
KW - Density functional calculations
KW - Diels–Alder
KW - Molecular electron density theory
KW - Pericyclic reactions
KW - Reaction mechanisms
UR - http://www.scopus.com/inward/record.url?scp=85043269049&partnerID=8YFLogxK
U2 - 10.1002/ejoc.201701350
DO - 10.1002/ejoc.201701350
M3 - Article
AN - SCOPUS:85043269049
SN - 1434-193X
VL - 2018
SP - 1107
EP - 1120
JO - European Journal of Organic Chemistry
JF - European Journal of Organic Chemistry
IS - 9
ER -