N'-(4-Methoxy-benzyl-idene)-4-nitro-benzo-hydrazide methanol solvate

Experimental and computational evidence for stabilising parallel, offset π[C(O)N(H)NC]⋯π(phenyl) interactions in acetohydrazide derivatives

Stabilising π[C(O)N(H)NC]⋯π(phenyl) interactions are described.

N'-(3-Methoxy-benzyl-idene)-4-nitro-benzohydrazide monohydrate

There are two independent formula units in the asymmetric unit of the title compound, C(15)H(13)N(3)O(4)·H(2)O. The C=C-N-C torsion angle of the methyl-idenehydrazide group is 174.3 (2)° in one mol-ecule and 178.6 (2)° in the other. The dihedral angles between the two benzene rings in the two mol-ecules are 4.17 (12) and 3.58 (12)°. In the crystal structure, inter-molecular O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds link the components into a two-dimensional network and additional stabilization is provided by weak inter-molecular C-H⋯O hydrogen bonds.

4-Nitro-N'-[(E)-3-pyridylmethyl-idene]benzohydrazide

In the title moleclue, C(13)H(10)N(4)O(3), the methyl-idene-hydrazide [-C(=O)-N-N=C-] fragment is essentially planar, with a maximum deviation of 0.0228 (7) Å. The mean planes of the benzene and pyridine rings make dihedral angles of 25.44 (6) and 5.47 (7)°, respectively, with the mean plane of the methyl-idene-hydrazide fragment. In the crystal structure, inter-molecular N-H⋯N hydrogen bonds link mol-ecules into chains along the b axis. Additional stabilization is provided by weak inter-molecular C-H⋯O hydrogen bonds. The O atoms of the nitro group are disordered over two sets of sites of equal occupancy.

N′-(2-Hydroxy-5-chlorobenzylidene)-4-nitrobenzohydrazide methanol solvate

The title compound, C₁₄H₁₀ClN₃O₄·CH₄O, was synthesized from the reaction of 5-chloro­salicylaldehyde with 4-nitro­benzohydrazide in methanol. The Schiff base mol­ecule is nearly planar, with a dihedral angle of 9.1 (3)° between the two benzene rings. The methanol solvent mol­ecules are linked to the Schiff base mol­ecules by N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, forming chains running parallel to the a axis.

N'-(3,5-Dichloro-2-hydroxy-benzyl-idene)-3-methoxy-benzohydrazide methanol solvate

In the title compound, C(15)H(12)Cl(2)N(2)O(3)·CH(3)OH, the Schiff base mol-ecule is nearly planar, with a dihedral angle of 4.5 (2)° between the two benzene rings. An intra-molecular O-H⋯N hydrogen bond is observed. The methanol solvent mol-ecule is linked to the Schiff base mol-ecule through inter-molecular N-H⋯O and O-H⋯O hydrogen bonds.