Casting a new light on azide photochemistry: photolytic production of cyclic-N3.

The first postulated structure of the N(3) moiety appeared in a scientific journal in 1890 and was reported as a cyclic triangle with one N,N double bond and two N,N single bonds. Only in the last several years has our understanding of azides advanced to the point that we can now claim to know how to synthesize this prototypical bonding motif. This article examines the experiments and theory that were essential in reaching this point and suggests future directions of research on cyclic-N(3).