How does potassium cyanide react with an alkyl halide?
The cyanide species acts as the nucleophile.
And of course the reaction leads (generally) to a
The usual representation of the cyanide ion is as
Note that the length of the original carbon chain has been extended by one carbon. Because the nitrile group can be further elaborated, by reduction to give a primary amine for instance, or by hydrolysis to give a carboxyl group, this reaction offers some synthetic utility.