Chapter 28, Problem 28.10P

Interpretation Introduction

Interpretation:

The HOMO from the $\text{2π-}$ electron component and the LUMO from the $\text{4π-}$ electron component can also gives bonding in a $\left[\text{4}s+\text{2}s\right]$ cycloaddition is to be shown.

Concept introduction:

Cycloaddition reactions are pericyclic reactions that take place in two compounds containing pi bonds to form cyclic compounds. These reactions are concerted and stereospecific in nature. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in thermal conditions undergoes reaction in antarafacial fashion and polyene containing odd number of bonds undergo reaction in suprafacial fashion. The total number of bonds present in the alkenes is considered in the reaction.