Preparation of Azides from Hydrazines by using Dinitrogen Tetroxide as Nitrosonium Ion Source

Various hydrazines such as aryl-, carbonyl-, and sulfonyl-hydrazine were reacted with dinitrogen tetroxide to give the corresponding azides in excellent yields under mild ocnditions at low temperature $(-20-40^\circ{C)}$ in acetonitrile. The reaction appears to be initiated by formation of the .betha.-nitroso hydrazine intermediate which converts into the azide product.