N'-(2-Fluoro-benzo-yl)benzohydrazide

N'-(3-Bromo-5-chloro-2-hy-droxy-benzyl-idene)-2H-1,3-benzodioxole-5-carbo-hydrazide

The asymmetric unit of the title hydrazone compound, C(15)H(10)BrClN(2)O(4), contains two independent mol-ecules. The dihedral angles between the benzene rings are 38.7 (3)° in one mol-ecule and 24.3 (3)° in the other. Both mol-ecules exist in trans conformations with respect to the C=N double bonds of the central methyl-idene units. Intra-molecular O-H⋯N contacts are observed in both mol-ecules, forming S(6) rings. In the crystal, mol-ecules are linked through N-H⋯O hydrogen bonds into chains along the a axis.

2-Chloro-N'-(2-hy-droxy-3,5-diiodo-benzyl-idene)benzohydrazide

In the title compound, C(14)H(9)ClI(2)N(2)O(2), the dihedral angle between the benzene rings is 65.9 (2)° and an intra-molecular O-H⋯N hydrogen bond generates an S(6) ring. The mol-ecule has an E conformation about the C=N bond. In the crystal, mol-ecules are linked into C(4) chains propagating in [001] by N-H⋯O hydrogen bonds.

(E)-2-Fluoro-N′-(4-nitrobenzylidene)benzohydrazide

In the title hydrazone compound, C₁₄H₁₀FN₃O₃, the dihedral angle between the two substituted benzene rings is 13.7 (3)°. The mol­ecule exists in a trans configuration with respect to the central methyl­idene unit. In the crystal, mol­ecules are linked through inter­molecular N—H⋯O hydrogen bonds, forming chains along the a axis.

(E)-4-Meth-oxy-N'-(4-nitro-benzyl-idene)benzohydrazide methanol monosolvate

The hydrazone mol­ecule of the title compound, C₁₅H₁₃N₃O₄·CH₄O, is nearly planar, with a dihedral angle between the two benzene rings of 1.2 (4)°. The mol­ecule exists in a trans configuration with respect to the central methyl­idene unit. In the crystal, the benzohydrazide and methanol mol­ecules are linked through inter­molecular O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds, forming chains along the a axis.

(E)-2-Meth-oxy-N'-(4-nitro-benzyl-idene)benzohydrazide

In the title compound, C(15)H(13)N(3)O(4), the mol-ecule exists in a trans configuration with respect to the methyl-idene unit. The dihedral angle between the two benzene rings is 6.8 (2)°. The C-N-NH-C torsion angle is 3.4 (3)°. The mol-ecule possesses an intra-molecular N-H⋯O hydrogen bond. In the crystal structure, adjacent mol-ecules are linked through inter-molecular C-H⋯O hydrogen bonds, forming dimers.

(E)-N'-(3,4-Dimethoxy-benzyl-idene)-2,4-dihydroxy-benzohydrazide methanol solvate

The title compound, C₁₆H₁₆N₂O₅·CH₃OH, was obtained from a condensation reaction of 3,4-dimethoxy­benzaldehyde and 2,4-dihydroxy­benzohydrazide. The non-H atoms of the Schiff base mol­ecule are approximately coplanar (r.m.s. deviation = 0.043 Å) and the dihedral angle between the two benzene rings is 1.6 (1)°. The mol­ecule adopts an E configuration with respect to the C=N double bond. An intra­molecular O—H⋯O hydrogen bond is observed. The Schiff base and methanol mol­ecules are linked into a two-dimensional network parallel to (10) by inter­molecular N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds.

(E)-N'-(3,4-Dihydroxy-benzyl-idene)-4-nitro-benzohydrazide

In the title Schiff base compound, C₁₄H₁₁N₃O₅, the dihedral angle between the two benzene rings is 1.6 (1)°. The mol­ecule displays an E configuration about the C=N bond. An intra­molecular O—H⋯O hydrogen bond is observed. In the crystal, mol­ecules are linked into layers parallel to (101) by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds. One of the hydroxyl groups is disordered over two positions, with occupancies of 0.643 (5) and 0.357 (5).

(E)-N′-(4-Hydroxybenzylidene)-4-hydroxybenzohydrazide methanol solvate

The title compound, C₁₄H₁₂N₂O₃·CH₄O, consists of a Schiff base mol­ecule and a methanol mol­ecule of crystallization. The Schiff base mol­ecule is nearly planar, the dihedral angle between the planes of the two benzene rings being 7.2 (2)°. The mol­ecule exists in the trans configuration with respect to the methyl­idene unit. In the crystal structure, the Schiff base and methanol mol­ecules are linked through O—H⋯O, N—H⋯O and O—H⋯N hydrogen bonds, forming a three-dimensional network.

(E)-4-Hydr-oxy-N'-(4-nitro-benzyl-idene)benzohydrazide

The mol-ecule of the title compound, C(14)H(11)N(3)O(4), is approximately planar, the dihedral angle between the planes of the two substituted benzene rings being 2.54 (7)°. The mol-ecule exists in a trans configuration with respect to the central methyl-idene unit. In the crystal structure, mol-ecules are linked through inter-molecular O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, forming layers parallel to (101). The O/N-H⋯O and C-H⋯O inter-actions form a pair of bifurcated acceptor bonds involving the cabon-yl/nitro O atom, generating an R(2) (1)(6) motif.

(E)-N'-(5-Bromo-2-methoxy-benzyl-idene)-3-methoxy-benzohydrazide

In the title compound, C₁₆H₁₅BrN₂O₃, there are two independent mol­ecules (A and B) in the asymmetric unit. The major difference between the two mol­ecules is the dihedral angle formed by the aromatic rings [72.6 (2) and 18.8 (2)° for A and B, respectively]. The benzohydrazide groups are not planar and the mol­ecules exist in trans configurations with respect to the methyl­idene units. The mol­ecular packing is stabilized by two inter­molecular N—H⋯O hydrogen bonds, forming chains parallel to the c axis. Only the A mol­ecules of the asymmetric unit are held together by π–π inter­actions [centroid–centroid distance = 3.714 (3) Å].

3-Bromo-N'-(2-hydr-oxy-3,5-diiodo-benzyl-idene)benzohydrazide monohydrate

Crystals of the title compound, C(14)H(9)BrI(2)N(2)O(2)·H(2)O, were obtained from a condensation reaction of 3-bromo-benzohydrazide with 3,5-diiodo-salicylaldehyde. The Schiff base mol-ecule assumes an E configuration with respect to the C=N bond, and the dihedral angle between the two benzene rings is 6.9 (2)°. An intra-molecular O-H⋯N hydrogen bond is observed in the Schiff base mol-ecule and may contribute to its overall near planarity. In the crystal structure, mol-ecules are linked through inter-molecular O-H⋯O and N-H⋯O hydrogen bonds, forming layers parallel to the bc plane. Short inter-molecular I⋯O contacts [2.930 (5) Å] are also found, linking the mol-ecules into zigzag chains along b.

(E)-N'-[1-(2-Hydroxy-phen-yl)ethyl-idene]-3-methoxy-benzohydrazide

In the title compound, C(16)H(16)N(2)O(3), the benzohydrazide group is not planar and the mol-ecule exists in a trans configuration with respect to the methyl-idene unit. The dihedral angle between the two substituted benzene rings is 26.9 (2)°. In the crystal structure, the mol-ecular packing is stabilized by intra-molecular O-H⋯N and inter-molecular N-H⋯O hydrogen bonds. The inter-molecular hydrogen bonding forms chains parallel to the b axis.

(E)-4-Bromo-N'-(2-nitro-benzyl-idene)benzohydrazide

The title compound, C(14)H(10)BrN(3)O(3), was obtained by a condensation reaction between 2-nitro-benzaldehyde and 4-bromo-benzohydrazide. The dihedral angle between the two benzene rings is 4.1 (2)°. The mol-ecule displays an E configuration about the C=N bond. In the crystal, mol-ecules are linked into a chain along [100] by inter-molecular N-H⋯O hydrogen bonds.

(E)-N'-(5-Bromo-2-methoxy-benzyl-idene)-4-methoxy-benzohydrazide

In the title compound, C(16)H(15)BrN(2)O(3), the benzohydrazide group is not planar and the mol-ecule exists in a trans configuration with respect to the methyl-idene unit. The dihedral angle between the two substituted benzene rings is 75.6 (2)°. In the crystal structure, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds involving carbonyl and amine functionalities, to form chains parallel to the c cell axis.

(E)-N'-(2-Chloro-5-nitro-benzyl-idene)-4-methoxy-benzohydrazide

In the title compound, C₁₅H₁₂ClN₃O₄, the benzohydrazide group is not planar and the mol­ecule exists in a trans configuration with respect to the methyl­idene unit. The dihedral angle between the two substituted benzene rings is 0.4 (3)°. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯O hydrogen bonds, forming chains parallel to the c axis.

(E)-N′-(4-Hydroxybenzylidene)-2-methoxybenzohydrazide

The title compound, C₁₅H₁₄N₂O₃, exists in the E configuration with respect to the central methyl­idene unit. The dihedral angle between the two substituted benzene rings is 22.0 (2)°. Within the mol­ecule there is an intra­molecular N—H⋯O hydrogen bond involving the hydro­zide H atom and the O atom of the meth­oxy substituent on the adjacent phenyl ring. In the crystal structure, mol­ecules are linked through inter­molecular O—H⋯O hydrogen bonds, forming zigzag chains along the b direction.

(E)-2-Chloro-N'-(2-hydr-oxy-1-naphthyl-methyl-ene)benzohydrazide

In the structue of the title compound, C₁₈H₁₃ClN₂O₂, a new Schiff base, the dihedral angle between the benzene and naphthyl ring system mean planes is 22.5 (2)°. The mol­ecule has an E configuration about the C=N bond, and an intra­molecular hydrogen bond involving the hydoxyl substituent on the naphthyl ring and the N′ atom of the hydrazide. The crystal structure is stabilized by inter­molecular N—H⋯O hydrogen bonds, forming one-dimensional chains running parallel to the a axis.

(E)-N'-(2-Hydr-oxy-4-methoxy-benzyl-idene)isonicotinohydrazide monohydrate

The title compound, C₁₄H₁₃N₃O₃·H₂O, was prepared by the reaction of 4-methoxy­salicylaldehyde and isonicotinohydrazide in ethanol. The Schiff base mol­ecule is not planar and has an E configuration with respect to the methyl­idene unit. The dihedral angle between the benzene and pyridine rings is 36.8 (2)°. In the mol­ecule there is an intra­molecular O—H⋯N hydrogen bond involving the hydroxyl substituent and the N atom of the 2-hydr­oxy-4-methoxy­benzyl­idene unit. In the crystal, the mol­ecules are linked through inter­molecular O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds, forming layers parallel to the bc plane.

N'-(5-Bromo-2-hydr-oxy-3-methoxy-benzyl-idene)isonicotinohydrazide

The title compound, C₁₄H₁₂BrN₃O₃, was prepared by reaction of 5-bromo-3-methoxy­salicylaldehyde and isonicotinohydrazide in methanol. The mol­ecule is not planar and adopts a trans configuration with respect to the C=N bond. There is an intra­molecular O—H⋯N hydrogen bond in the mol­ecule. The dihedral angle between the benzene and pyridine rings is 12.2 (2)°. In the crystal structure, mol­ecules are linked through inter­molecular N—H⋯N hydrogen bonds, forming chains running along the c-axis direction.