Preferred Label : pseudopericyclic;
IUPAC definition : A concerted transformation is pseudopericyclic if the primary changes in bonding occur
within a cyclic array of atoms at one (or more) of which nonbonding and bonding atomic
orbitals interchange roles. A formal example is the enol enol prototropy of pentane-2,4-dione
(acetylacetone). Because the π- and σ-atomic orbitals that interchange roles are
orthogonal, such a reaction does not proceed through a fully conjugated transition
state and is thus not a pericyclic reaction and therefore not governed by the rules
that express orbital symmetry restrictions applicable to pericyclic reactions.;
Origin ID : P04932;
See also
A concerted transformation is pseudopericyclic if the primary changes in bonding occur
within a cyclic array of atoms at one (or more) of which nonbonding and bonding atomic
orbitals interchange roles. A formal example is the enol enol prototropy of pentane-2,4-dione
(acetylacetone). Because the π- and σ-atomic orbitals that interchange roles are
orthogonal, such a reaction does not proceed through a fully conjugated transition
state and is thus not a pericyclic reaction and therefore not governed by the rules
that express orbital symmetry restrictions applicable to pericyclic reactions.
