Von Braun reaction
The von Braun reaction is an organic reaction in which a tertiary amine reacts with cyanogen bromide to an organocyanamide.
An example is the reaction of dimethyl-α-naphthylamine:
The reaction mechanism consists of two nucleophilic substitutions: the amine is the first nucleophile displacing the bromine atom which then acts as the second nucleophile. In following the mechanism is described using trimethylamine as example:
First, the trimethylamine reacts with the cyanogen bromide to form a cyano group. This results in a quaternary ammonium salt, which in the next step reacts by splitting off bromomethane to give the dimethylcyanamide. This is a second-order nucleophilic substitution.
