In the title compound, C11H10ClN3O, the quinoline ring system is essentially planar, the r.m.s. deviation for the non-H atoms being 0.014 (2) Å with a maximum deviation from the mean plane of 0.0206 (14) Å for the C atom bonded to the –CH—N=NH2 group. In the crystal, molecules are linked via N—H⋯O and N—H⋯N hydrogen bonds, forming zigzag layers parallel to (010).

In the title compound, C18H17ClN2O, the quinoline ring system is essentially planar; the r.m.s. deviation for the non-H atoms is 0.04 Å with a maximum deviation from the mean plane of 0.026 (4) Å for the C atom bonded to the –CH2– group. The meth­oxy-substituted benzene ring forms a dihedral angle of 70.22 (4)° with this ring system. The crystal structure can be described as zigzag layers in which the quinoline ring systems are parallel to (011) and molecules are connected via inter­molecular N—H⋯N hydrogen bonds, forming chains along [100]. The crystal studied was an inversion twin with a 0.86 (5):0.14 (5) domain ratio.