Concept explainers
(a)
Interpretation: The product formed by the thermal electrocyclic ring closure of given triene N is to be determined.
Concept introduction: Electrocyclic reactions are pericyclic reactions which takes place by concerted mechanism. These reactions involve ring opening or ring closure in a conjugated polyene.
(b)
Interpretation: The product formed by the photochemical electrocyclic ring closure of given triene N is to be determined.
Concept introduction: Electrocyclic reactions are pericyclic reactions which takes place by concerted mechanism. These reactions involve ring opening or ring closure in a conjugated polyene.
(c)
Interpretation: The given processes are to be labeled as conrotatory or disrotatory.
Concept introduction: Electrocyclic reactions are pericyclic reactions which takes place by concerted mechanism. These reactions involve ring opening or ring closure in a conjugated polyene. In Conratotory process, the orbitals where rearrangement is taking place rotates in clockwise direction and in disrotatory process the atomic orbitals rotates in opposite direction.
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