Crystals of the title compound, C(13)H(10)N(4)O(4), were obtained from a condensation reaction of benzaldehyde and 2,4-dinitrophenylhydrazine. The molecule assumes an approximately planar E configuration. Within the dinitrophenyl moiety, the average distance for the aromatic C-C bonds close to the imino group [1.417 (3) A] is appreciably longer than the average distance for the other aromatic C-C bonds in the same phenyl ring [1.373 (3) A]. This increased distance may be a result of the overlap of the non-bonding orbital of the imino N atom with the pi orbitals of the arene. It is likely that pi-pi stacking exists in the crystal structure.

A highly efficient and convenient method for the synthesis of 1,2,4,5-tetrasubstituted imidazoles from readily accessible 2-azido acrylates and nitrones has been developed. This reaction proceeded under mild conditions without the assistance of any metal, acid, or base.

Crystals of the title compound, C15H15N3O, were obtained from a condensation reaction of benzohydrazide and 1-(4-amino­phen­yl)ethanone. The mol­ecule assumes an E configuration with the amino­phenyl and benzohydrazide units located on opposite sites of the C=N double bond. In the crystal structure, the benzene rings of the mol­ecule are slightly twisted with respect to the central hydrazide, the dihedral angles being 18.22 (12) and 27.62 (12)°. The crystal structure contains inter­molecular N—H⋯O and weak C—H⋯N hydrogen bonding.

Key indicatorsSingle-crystal X-ray study T = 295 K Mean (C-C) = 0.003 Å R factor = 0.037 wR factor = 0.115 Data-to-parameter ratio = 19.9For details of how these key indicators were automatically derived from the article, see

Crystals of the title compound, C12H10N4O5, were obtained from a condensation reaction of 2,4-dinitro­phenyl­hydrazine and 2-furyl methyl ketone. The mol­ecule displays a nearly planar structure, and the furan ring is slightly twisted by a dihedral angle of 12.62 (6)° with respect to the phenyl­hydrazone plane. The face-to-face separation of 3.287 (7) Å between parallel benzene rings of adjacent mol­ecules indicates the existence of π–π stacking between dinitro­phenyl rings in the crystal structure.