Chapter 6, Problem 15PP

Interpretation Introduction

Interpretation:

Thereaction of propyl bromide with sodium cyanide $\left(\text{NaCN}\right)$ whether occurs faster in $\text{DMF}$ or in ethanol is to be explained.

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.

In organic chemistry, the nucleophilic substitution reaction thatconsists of bimolecular reaction, one-step mechanism, and no carbocation is known as ${\text{S}}_{\text{N}}2$ reaction.

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

$N,N-\text{Dimethylformamide}\left(\text{DMF}\right)$ is considered an organic compound with the formula ${\left({\text{CH}}_{\text{3}}\right)}_{\text{2}}\text{NCH}$. It is a polar aprotic solvent, which is used in ${\text{S}}_{\text{N}}2$ reactions.

A chemical species thathas the tendency to donate an electron pair to an electrophile in order to form a chemical bondis known as nucleophile.

To form an alkyl halide, reaction takes place between halogen atoms and alkanes.

Cyanide ion $\left({\text{CN}}^{-}\right)$ is a nucleophile