Pericyclic Reaction
- Page ID
- 40862
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A pericyclic reaction is a concerted reaction in which the number of rings in the transition state is greater than the total number of rings in the reactant molecules.
Mechanism
- # covalent bonds broken = 3
- # covalent bonds formed = 3
- # covalent bonds broken + # covalent bonds formed = 3 + 3 = 6
- # steps = 1
Thus, the reaction is a concerted reaction. The transition state of the reaction can be drawn roughly as follows.
- # rings in the reactant molecule = 0
- # rings in the transition state = 1
- # rings in the transition state > # rings in the reactant molecule
Thus, the reaction is a pericyclic reaction. For more examples of pericyclic reactions, see Cope elimination, Claisen rearrangement, Diels-Alder reaction