91Ó°ÊÓ

You can prepare nitriles from methyl and $\mathbf{1}\mathbf{°}$alkylhalides via ${\mathbf{S}}_{\mathbf{N}}\mathbf{2}$substitution reaction. Cyanides are used as a reagent for such reactions.

a. The reaction a is an example of${\mathrm{S}}_{\mathrm{N}}2$ substitution reaction by cyanide. The product is shown below:

Nucleophilic reaction of cyanide with alkyl halide

The carbon atom of the cyanide group acts as a nucleophile in nitriles, and thus takes part in nucleophilic substitution with reagents like water, hydrides, and organometals.

The hydrolysis of nitriles is an example of a reaction where water acts as a nucleophile.

The reactions b and c are examples of hydrolysis in acidic and basic conditions, respectively. The product is given below:

b.

Hydrolysis in acidic condition

c.

Hydrolysis in basic condition