Table 2. Comparison of C=O and N—N bond lengths (Å) between the title compound and reported pyrazolone compounds.

Compound	C=O	N—N
C13H14N2O2a	1.313 (2)	1.395 (2)
C19H16N2O2a	1.261 (2)	1.404 (2)
C15H12N2O2Sa	1.246 (2)	1.373 (2)
C22H15ClN2Oc	1.228 (2)	1.405 (2)
C16H11N3Oc	1.252 (3)	1.412 (4)
C16H10ClN3Oc	1.250 (5)	1.420 (5)
C10H8N4O5d	1.207 (3)	1.412 (2)
C15H11ClN2Oe	1.213 (2)	1.404 (2)

Notes: (a) Holzer et al. (1999 ▶); (b) Bovio et al. (1974 ▶); (c) Ferretti et al. (1985 ▶); (d) Dardonville et al. (1998 ▶); (e) this work.