3-Bromo N-Alkyl Cyanamides as Versatile Building Blocks

3-Bromo N-alkyl cyanamides are accessible in one simple synthetic operation from N-alkyl azetidines reacting with cyanogen bromide. These unexplored building blocks combine two extremely useful electrophilic moieties: an alkyl bromide and a cyanamide. We demonstrate herein that they can be transformed into a range of nitrogen-containing molecules, and especially cyclic guanidines, accessible in enantiomerically pure form. Considering the large structural diversity of available azetidines, this contribution complements the use of these strained heterocycles in diversity-oriented synthesis.