In the title compound, C15H17N3O2, the dihedral angle between the planes of the
pyrazolidine and phenyl rings is 29.91 (6). The piperidine ring adopts a chair
conformation. In the crystal, molecules are linked into chains running parallel to
the a-axis direction by a combination of N—H  O and C—H  O hydrogen
bonds. Furthermore, there exist C—H   interactions and – stacking
interactions [centroid-to-centroid distance = 3.5274 (10) A ° ] between the
pyrazolidine rings of adjacent molecules.