Chapter 30.SE, Problem 30AP

Interpretation Introduction

Interpretation:

A mechanism for the thermal rearrangement of vinyl substituted cyclopropanes in to cyclopentenes identifying the pericyclic process involved is to be proposed.

Concept introduction:

Sigmatropic rearrangements involve the migration of a σ bond present at the end or in the middle of the system across the π electron system from one position to another. They are represented by [m,n] where m and n represents the number of atoms between the bond being broken and the bond being formed in two directions.

If even number of electron pair is involved then thermal reaction occur through antarafacial pathway and photochemical reactions occur through suprafacial pathway.

If odd number of electron pair is involved then thermal reaction occur through suprafacial pathway and photochemical reactions occur through antarafacial pathway.

To propose:

A mechanism for the thermal rearrangement of vinyl substituted cyclopropanes in to cyclopentenes identifying the pericyclic process involved.