On the Question of Stepwise [4+2] Cycloaddition Reactions and Their Stereochemical Aspects
Radomir Jasiński
Abstract
Even at the end of the twentieth century, the view of the one-step [4+2] cycloaddition (Diels-Alder) reaction mechanism was widely accepted as the only possible one, regardless of the nature of the reaction components. Much has changed in the way these reactions are perceived since then. In particular, multi-step mechanisms with zwitterionic or diradical intermediates have been proposed for a number of processes. This review provided a critical analysis of such cases.
Topics & Concepts
CycloadditionDiradicalChemistryMechanism (biology)Reaction mechanismComputational chemistryStepwise reactionComputer scienceOrganic chemistryCatalysisPhilosophyEpistemologyPhysicsOrder of reactionKineticsSinglet stateExcited stateQuantum mechanicsNuclear physicsReaction rate constantOrganic Chemistry Cycloaddition ReactionsFree Radicals and AntioxidantsOxidative Organic Chemistry Reactions