Crystal structure of (1Z)-1-(4-chloro­benzyl­idene)-5-(4-meth­oxy­phen­yl)-3-oxopyrazolidin-1-ium-2-ide

The title mol­ecule, C(17)H(15)ClN(2)O(2), is L-shaped with the 4-chloro­benzyl­idene ring almost coplanar with the planar pyrazolidine ring (r.m.s. deviation = 0.020 Å), making a dihedral angle of 4.83 (17)°. The 4-meth­oxy­phenyl ring is almost normal to the mean plane of the pyrazolidine ring and the 4-chloro­benzyl­idene ring, with dihedral angles of 87.36 (17) and 89.23 (16)°, respectively. The pyrazolidine ring occurs in the betaine form with a Z configuration for the exocyclic C=N bond. In the crystal, C—H⋯O and C—H⋯π inter­actions generate ribbons of mol­ecules along [1-10].