6-Chloro-3-[4-(hexyloxy)phenyl]-[1,2,4]triazolo[4,3-b]pyridazine

Molecules of the title compound, C17H19ClN4O, are essentially planar, the dihedral angles between the planes of the tetraazaindene ring system and the benzene ring and between the benzene ring and the hexyloxy chain being 1.56 (10)° and 5.02 (17)°, respectively. In the crystal, pairs of molecules are connected via π–π interactions between the phenyl ring and the triazolopyridazine moiety.