The von Braun Cyanogen Bromide Reaction

The reaction of a tertiary amine with cyanogen bromide was first described in 1900 by Julius von Braun who elaborated the reaction to such an extent that it bears his name. Generally, a tertiary amine reacts with cyanogen bromide to yield an alkyl bromide and a disubstituted cyanamide. The direct conversion of secondary amines to disubstituted cyanamides with cyanogen bromide proceeds in low yield because some of the amine is converted to its hydrobromide. The material in this chapter is limited to a discussion of the reaction of tertiary amines with cyanogen bromide.

Keywords: von Braun reaction; cyanogen bromide; alicyclic amines; cyclic amines; alkaloids; synthetic applications; experimental conditions