Organic compounds that contain an azide functional group. Alkyl azides can be prepared by halide displacement, from alcohols via a variant of the Mitsunobu reaction with diphenyl phosphoryl azide, by ring-opening of epoxides and aziridines or by azidation of alkenes. Aryl azides can be prepared by displacement of the appropriate diazonium salt with sodium azide or with a sulfonamide first to a diazoamino sulfinate and then on hydrolysis the azide and a sulfinic acid (Dutt–Wormall reaction). Organic azides engage in useful organic reactions. They can be reduced to amines by hydrogenolysis or with a phosphines in the Staudinger reaction. They are also popular for their participation in the "click reaction" with alkynes to yield substituted 1,2,3-triazoles. Many of them are explosophores and poisons.