Chapter 6, Problem 5PP

Interpretation Introduction

Interpretation:

The nucleophilic substitution reaction of $trans\text{-1-bromo-4-}tert\text{-butylcyclohexane}$ with iodide ion using chair conformations is to be shown.

Concept introduction:

Electrophiles are electron-deficient species, which has positive or partially positive charge. Lewis acids are electrophiles, which accept electron pair.

Nucleophiles are electron-rich species, which has negative or partially negative charge. Lewis bases are nucleophiles, which donate electron pair.

Substitution reaction: A reaction in which one of the hydrogen atoms of a hydrocarbon or a functional group is substituted by any other functional group is called substitution reaction.

Nucleophilic substitution reaction is a reaction in which an electron rich nucleophile attacks the positive or partial positive charge of an atom or a group of atoms to replace a leaving group.

The ${\text{S}}_{\text{N}}\text{2}$ reaction occurs in the secondary alkyl halides with the inversion of configuration.

The ${\text{S}}_{\text{N}}\text{2}$ reaction takes place in one step. The nucleophile attacks the alkyl halide from the side opposite to the leaving group resulting in the inversion of configuration.

In double bond or cyclic compounds, if two same functional groups are present on the same side of the double bond or cyclic compound, the given compound can be labeled as cis.

If the two functional groups are present on the different sides of the double bond or cyclic compound, the given compound can be labeled as Trans.

Cis-trans isomerism exists in the compounds in which similar groups are present on the adjacent carbon atoms.

Chair conformations: It is the most stable conformation, which accurately shows the spatial arrangement of atoms.

Equatorial bonds are parallel to the average plane of the ring, while axial bonds are perpendicular to the average plane of the ring.

The conformation having bonds at the equatorial positions are more stable than those with bonds at the axial position.

On flipping the cyclohexane ring, axial bonds become equatorial bonds and equatorial bonds becomes axial bond.

Bulkier group acquires equatorial positions to form stable conformer due to steric factors.