Reaction mechanisms Part (ii) Pericyclic reactions

Abstract

This report surveys the 2007 literature on mechanisms of pericyclic reactions. One recurring theme in this year’s reports is catalysis. Several studies addressed the catalysis of cycloaddition reactions by preorganization (via encapsulation, hydrogen bond directed precomplex formation, or hydrophobic effects) or selective transition state stabilization (viahydrogen bonding interactions) and the acceleration of sigmatropic shifts by selective transition state stabilization (viahydrogen bonding, transition metal complexation, and weak interactions with halogens) or addition of an electron. In addition, the mechanisms of several interesting cascades consisting of multiple types of pericyclic reactions linked in tandem were examined in detail.