Phenyl azide

Overview
Phenylazide is an organic compound with the formula C6H5N3. It is one of the prototypical organic azides. It has a pungent odor.

It is prepared by the diazotization of phenylhydrazine with nitrous acid:
 * C6H5NHNH2 +  HNO2  → C6H5N3  +  2 H2O

The structure consists of a linear N=N=N substituent bound to a phenyl group. The C-N=N angle is approximately 120°.

Chemical reactions
C6H5N3 is used to make heterocycles via cycloaddition to alkenes and especially alkynes, particularly those bearing electronegative substituents. It reacts with triphenylphosphine to give the Staudinger reagent C6H5NP(C6H5)3. Thermolysis induces loss of N2 to give the highly reactive phenylnitrene C6H5N.

Other fundamental phenyl-N molecules
Related phenyl-N building blocks include C6H5NH2, C6H5NO, C6H5NO2, C6H5NHOH, C6H5NHNH2, and C6H5N 2 +.

Safety
A protective blast shield is needed during purification and handling. Distillation temperatures should be as low a possible. Organic Syntheses recommends 5mm Hg to give a boiling point of “66–68 °C/21 mm. with a bath temperature of 70–75 °C.” The pure substance may be stored in the dark, cold, and even then the shelf-life is only weeks.