3-(o-Carboxyphenyl)-1-ethyltriazene 1-Oxide

The structure determination of the title compound, C₉H₁₁N₃O₃, establishes the N-oxide form of triazene. The two molecules in the asymmetric unit are hydrogen bonded and have different conformations. One molecule is essentially planar while in the other molecule, the terminal ethyl and carboxy groups deviate considerably from the corresponding molecular plane. The planar phenyl ring and the trigonal-planar geometry about the triazene N atom bonded to the phenyl ring suggest a resonance interaction extending over adjacent atoms. Intermolecular hydrogen bonds link the molecules into infinite chains.