Crystal structure of 2-[2-(pyridin-3-yl)diazen-1-yl]aniline

The crystal structure of the title compound, C(11)H(10)N(4), comprises mol­ecules in a trans conformation for which all the atoms are located in general positions. The six-membered rings are coplanar and this arrangement might be stabilized by intra­molecular N—H⋯N hydrogen bonding. In the crystal, the mol­ecules are linked into helical chains parallel to the b axis via N—H⋯N hydrogen bonding. The mol­ecular packing shows a herringbone-like pattern along the a axis. Comparison of the X-ray powder diffraction with that calculated from single crystal data proves that a pure crystalline phase was obtained and UV–Vis measurements reveal that only the trans isomer is present.