Chapter 6, Problem 44DSP

Interpretation Introduction

Interpretation:

The major product for the reaction shown is to be identified.

Concept Introduction:

In general, ${\text{S}}_{\text{N}}2$ reactions of alkyl halides show the following dependence of rate on structure: $\text{primary > secondary > tertiary}$.

Primary alkyl halides are less crowded at the site of substitution than secondary and tertiary alkyl halides, and thus, react faster in substitution by ${\text{S}}_{\text{N}}2$ mechanism.

For ${\text{S}}_{\text{N}}2$ reactions, the rate of substitution depends on the nature of nucleophile and its concentration. ${\text{S}}_{\text{N}}2$ reactions are undergone at a faster rate in presence of strong nucleophiles.

Polar aprotic solvents give fastest rate of substitution by ${\text{S}}_{\text{N}}2$ mechanism.

Nucleophile attacks carbon atoms from a side opposite bond to a leaving group, and hence, inversion of configuration takes place in ${\text{S}}_{\text{N}}2$ mechanism pathway.

Exchange of two groups in a Fischer projection reverses the configuration of the chirality center.