organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

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

aCollege of Chemistry and Chemical Engineering, Qinzhou University, Qinzhou, Guangxi 535000, People's Republic of China, and bGuangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University, Nanning, Guangxi 530004, People's Republic of China
*Correspondence e-mail: ljmmarise@163.com

(Received 4 May 2012; accepted 8 May 2012; online 16 May 2012)

The title Schiff base compound, C14H12N4O3, displays an E conformation with respect to the C=N double bond [1.268 (3) Å]. The dihedral angle between the benzene rings is 3.2 (5)°, consistent with an essentially planar mol­ecule. In the crystal, N—H⋯O and N—H⋯N hydrogen bonds, as well as C—H⋯O inter­actions, link the mol­ecules into layers that stack along the c axis.

Related literature

For the coordination chemistry of Schiff base and hydrazone compounds, see: Kucukguzel et al. (2006[Kucukguzel, G., Kocatepe, A., De Clercq, E., Sahi, F. & Gulluce, M. (2006). Eur. J. Med. Chem. 41, 353-359.]); Khattab et al. (2005[Khattab, S. N. (2005). Molecules, 10, 1218-1228.]); Karthikeyan et al. (2006[Karthikeyan, M. S., Prasad, D. J., Poojary, B., Bhat, K. S., Holla, B. S. & Kumari, N. S. (2006). Bioorg. Med. Chem. 14, 7482-7489.]). For a closely related 4-amino­benzohydrazide and its Schiff base structures and further background references, see: Xu (2012[Xu, S.-Q. (2012). Acta Cryst. E68, o1320.]); Shi & Li (2012[Shi, Z.-F. & Li, J.-M. (2012). Acta Cryst. E68, o1546-o1547.]); Bakir & Green (2002[Bakir, M. & Green, O. (2002). Acta Cryst. C58, o263-o265.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12N4O3

  • Mr = 284.28

  • Monoclinic, P 21

  • a = 6.4594 (13) Å

  • b = 4.5998 (13) Å

  • c = 20.598 (5) Å

  • β = 95.08 (4)°

  • V = 609.6 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 296 K

  • 0.25 × 0.18 × 0.10 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.976, Tmax = 0.989

  • 4632 measured reflections

  • 2710 independent reflections

  • 1516 reflections with I > 2σ(I)

  • Rint = 0.048

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.111

  • S = 1.05

  • 2710 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯N1i 0.89 2.44 3.287 (4) 162
N1—H1B⋯O1ii 0.89 2.35 3.164 (3) 153
N2—H2⋯O1iii 0.86 2.13 2.843 (3) 142
C2—H2A⋯O1ii 0.93 2.56 3.329 (3) 140
Symmetry codes: (i) [-x+3, y+{\script{1\over 2}}, -z]; (ii) x+1, y-1, z; (iii) x, y-1, z.

Data collection: SMART (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Schiff bases are one of the most prevalent mixed-donor ligands in the field of coordination chemistry. They play an important role in the development of coordination chemistry related to catalysis and enzymatic reactions, magnetism, and supramolecular architectures (Karthikeyan et al., 2006; Khattab, 2005; Kucukguzel et al., 2006). Structures of Schiff bases derived from substituted 4-aminobenzohydrazide and closely related to the title compound have been reported earlier (Xu, 2012; Shi & Li, 2012; Bakir & Green, 2002). In order to explore new anti-bacterial compounds, a new hydrazone derivative was prepared and characterized crystallographically.

As shown in Fig. 1, the asymmetric unit of the title compound, (I), contains one independent molecule displaying an E configuration with respect to its CN double bond. The dihedral angle between the two benzene rings is 3.2 (5)°. The bond lengths and angles are as expected for a compound of this type and agree with the other ligands belonging to the hydrazone series. The C8N3 and C7O1 bond lengths of 1.268 (3) and 1.226 (3) Å, respectively, are the expected values for such double bonds. In the crystal packing, it is noted that amino-H (H1A, H1B) and amide-H2A atoms are involved in forming intermolecular N—H···O and N—H···N hydrogen bonds (Fig. 2 and Table 1), linking the molecules into a two-dimensional layer structure that stacks along the c axis. Weak C—H···O interactions are also noted within the layer.

Related literature top

For the coordination chemistry of Schiff base and hydrazone compounds, see: Kucukguzel et al. (2006); Khattab et al. (2005); Karthikeyan et al. (2006). For a closely related 4-aminobenzohydrazide and its Schiff base structures and further background references, see: Xu (2012); Shi & Li (2012); Bakir & Green (2002).

Experimental top

To a methanol solution (20 ml) of 2-nitrobenzaldehyde (1 mmol, 0.151 g) and 4-aminobenzohydrazide (1 mmol, 0.151 g), a few drops of acetic acid were added. The mixture was refluxed for 2 h and then cooled to room temperature to give a yellow solution. Crystals of the title compound were formed by gradual evaporation of the solvent over a period of 6 days at room temperature.

Refinement top

H-atoms were placed in calculated positions (C—H = 0.93 and N—H = 0.86–0.89 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2Ueq(C or N). In the absence of significant anomalous scattering effects, 1120 Friedel pairs were averaged in the final refinement.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids at the 30% probability level.
[Figure 2] Fig. 2. Crystal packing in the title compound where molecules are linked via N—H···O and N–H···N hydrogen bonds (dashed lines). Except for those involved in hydrogen-bonding interactions, H atoms have been omitted for clarity.
(E)-4-Amino-N'-(2-nitrobenzylidene)benzohydrazide top
Crystal data top
C14H12N4O3F(000) = 296
Mr = 284.28Dx = 1.549 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 7138 reflections
a = 6.4594 (13) Åθ = 1.4–27.5°
b = 4.5998 (13) ŵ = 0.11 mm1
c = 20.598 (5) ÅT = 296 K
β = 95.08 (4)°Block, yellow
V = 609.6 (3) Å30.25 × 0.18 × 0.10 mm
Z = 2
Data collection top
Bruker SMART CCD area-detector
diffractometer
2710 independent reflections
Radiation source: fine-focus sealed tube1516 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.048
ϕ and ω scansθmax = 27.5°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 87
Tmin = 0.976, Tmax = 0.989k = 65
4632 measured reflectionsl = 2624
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0576P)2 + 0.2479P]
where P = (Fo2 + 2Fc2)/3
2710 reflections(Δ/σ)max < 0.001
190 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C14H12N4O3V = 609.6 (3) Å3
Mr = 284.28Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.4594 (13) ŵ = 0.11 mm1
b = 4.5998 (13) ÅT = 296 K
c = 20.598 (5) Å0.25 × 0.18 × 0.10 mm
β = 95.08 (4)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2710 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1516 reflections with I > 2σ(I)
Tmin = 0.976, Tmax = 0.989Rint = 0.048
4632 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.111H-atom parameters constrained
S = 1.05Δρmax = 0.27 e Å3
2710 reflectionsΔρmin = 0.22 e Å3
190 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.6908 (3)1.3470 (4)0.16727 (9)0.0252 (4)
O20.5696 (3)0.5737 (5)0.40854 (9)0.0335 (5)
O30.3389 (3)0.4666 (5)0.47354 (9)0.0338 (5)
N11.4552 (3)0.7167 (6)0.05402 (10)0.0248 (5)
H1A1.50390.82520.02360.030*
H1B1.55830.64430.08110.030*
N20.6727 (3)0.9187 (5)0.21889 (9)0.0193 (4)
H20.70970.74150.22150.023*
N30.5305 (3)1.0250 (5)0.25824 (9)0.0198 (4)
N40.3968 (3)0.6017 (5)0.42806 (10)0.0241 (5)
C11.2814 (3)0.8062 (6)0.08357 (11)0.0196 (5)
C21.2309 (3)0.6722 (6)0.14030 (11)0.0194 (5)
H2A1.31340.52340.15850.023*
C31.0579 (3)0.7606 (6)0.16970 (11)0.0190 (5)
H31.02710.67150.20780.023*
C40.9293 (3)0.9809 (6)0.14297 (11)0.0188 (5)
C50.9786 (3)1.1101 (6)0.08586 (11)0.0200 (5)
H50.89381.25550.06710.024*
C61.1522 (3)1.0262 (6)0.05623 (11)0.0213 (5)
H61.18271.11620.01820.026*
C70.7535 (3)1.0973 (6)0.17592 (11)0.0189 (5)
C80.4572 (3)0.8400 (6)0.29566 (11)0.0196 (5)
H80.50660.65250.29780.024*
C90.2917 (3)0.9327 (6)0.33548 (11)0.0188 (5)
C100.2529 (3)0.8118 (6)0.39485 (11)0.0194 (5)
C110.0792 (4)0.8859 (6)0.42611 (11)0.0230 (6)
H110.05550.79750.46500.028*
C120.0568 (4)1.0909 (7)0.39888 (12)0.0264 (6)
H120.17351.14050.41910.032*
C130.0189 (4)1.2225 (6)0.34132 (12)0.0245 (5)
H130.10851.36470.32360.029*
C140.1523 (3)1.1439 (6)0.30967 (12)0.0218 (5)
H140.17461.23310.27070.026*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0270 (9)0.0148 (9)0.0353 (10)0.0046 (7)0.0107 (7)0.0022 (8)
O20.0270 (8)0.0396 (13)0.0347 (10)0.0120 (9)0.0078 (7)0.0073 (10)
O30.0390 (10)0.0295 (12)0.0336 (10)0.0006 (9)0.0069 (8)0.0107 (10)
N10.0206 (9)0.0285 (13)0.0269 (10)0.0033 (10)0.0103 (7)0.0009 (11)
N20.0187 (9)0.0158 (10)0.0247 (9)0.0043 (8)0.0083 (7)0.0010 (9)
N30.0182 (8)0.0198 (11)0.0223 (9)0.0026 (8)0.0061 (7)0.0025 (9)
N40.0269 (10)0.0202 (11)0.0256 (10)0.0020 (9)0.0052 (8)0.0012 (10)
C10.0170 (10)0.0202 (13)0.0222 (10)0.0017 (10)0.0047 (8)0.0073 (11)
C20.0182 (10)0.0164 (13)0.0236 (11)0.0029 (9)0.0021 (8)0.0020 (10)
C30.0193 (10)0.0154 (13)0.0232 (11)0.0012 (9)0.0060 (8)0.0008 (10)
C40.0164 (9)0.0189 (13)0.0215 (10)0.0004 (10)0.0034 (7)0.0039 (10)
C50.0204 (10)0.0170 (12)0.0227 (11)0.0012 (10)0.0024 (8)0.0011 (11)
C60.0232 (11)0.0208 (13)0.0208 (10)0.0012 (10)0.0068 (8)0.0008 (10)
C70.0181 (10)0.0171 (12)0.0222 (11)0.0012 (10)0.0044 (8)0.0026 (11)
C80.0188 (9)0.0181 (12)0.0223 (10)0.0010 (10)0.0038 (8)0.0014 (11)
C90.0157 (9)0.0153 (12)0.0258 (11)0.0009 (9)0.0045 (8)0.0028 (10)
C100.0188 (10)0.0153 (12)0.0243 (11)0.0014 (10)0.0028 (8)0.0007 (11)
C110.0251 (11)0.0230 (15)0.0223 (11)0.0018 (11)0.0094 (8)0.0004 (11)
C120.0203 (10)0.0318 (16)0.0283 (12)0.0023 (11)0.0084 (9)0.0031 (13)
C130.0223 (10)0.0216 (14)0.0293 (12)0.0035 (11)0.0020 (9)0.0028 (12)
C140.0215 (10)0.0187 (14)0.0254 (11)0.0013 (10)0.0035 (8)0.0010 (11)
Geometric parameters (Å, º) top
O1—C71.226 (3)C4—C51.380 (3)
O2—N41.226 (3)C4—C71.474 (3)
O3—N41.211 (3)C5—C61.378 (3)
N1—C11.386 (3)C5—H50.9300
N1—H1A0.8900C6—H60.9300
N1—H1B0.8900C8—C91.467 (3)
N2—C71.346 (3)C8—H80.9300
N2—N31.368 (3)C9—C101.386 (3)
N2—H20.8600C9—C141.397 (3)
N3—C81.268 (3)C10—C111.385 (3)
N4—C101.470 (3)C11—C121.378 (4)
C1—C21.385 (3)C11—H110.9300
C1—C61.398 (3)C12—C131.372 (4)
C2—C31.379 (3)C12—H120.9300
C2—H2A0.9300C13—C141.381 (3)
C3—C41.393 (3)C13—H130.9300
C3—H30.9300C14—H140.9300
C1—N1—H1A120.0C5—C6—H6119.9
C1—N1—H1B115.0C1—C6—H6119.9
H1A—N1—H1B111.2O1—C7—N2121.8 (2)
C7—N2—N3119.3 (2)O1—C7—C4122.1 (2)
C7—N2—H2120.4N2—C7—C4116.1 (2)
N3—N2—H2120.4N3—C8—C9118.3 (2)
C8—N3—N2115.1 (2)N3—C8—H8120.9
O3—N4—O2123.5 (2)C9—C8—H8120.9
O3—N4—C10118.12 (19)C10—C9—C14117.0 (2)
O2—N4—C10118.3 (2)C10—C9—C8125.2 (2)
C2—C1—N1119.9 (2)C14—C9—C8117.8 (2)
C2—C1—C6118.8 (2)C9—C10—C11121.9 (2)
N1—C1—C6121.0 (2)C9—C10—N4121.26 (19)
C3—C2—C1120.0 (2)C11—C10—N4116.7 (2)
C3—C2—H2A119.9C12—C11—C10119.5 (2)
C1—C2—H2A119.9C12—C11—H11120.2
C2—C3—C4121.2 (2)C10—C11—H11120.2
C2—C3—H3119.4C11—C12—C13119.7 (2)
C4—C3—H3119.4C11—C12—H12120.2
C5—C4—C3118.2 (2)C13—C12—H12120.2
C5—C4—C7119.0 (2)C12—C13—C14120.6 (2)
C3—C4—C7122.6 (2)C12—C13—H13119.7
C6—C5—C4121.0 (2)C14—C13—H13119.7
C6—C5—H5119.4C13—C14—C9121.2 (2)
C4—C5—H5119.4C13—C14—H14119.4
C5—C6—C1120.2 (2)C9—C14—H14119.4
C7—N2—N3—C8177.7 (2)N3—C8—C9—C10152.8 (2)
N1—C1—C2—C3179.9 (2)N3—C8—C9—C1432.2 (3)
C6—C1—C2—C31.3 (4)C14—C9—C10—C112.8 (4)
C1—C2—C3—C40.9 (4)C8—C9—C10—C11172.1 (2)
C2—C3—C4—C50.1 (4)C14—C9—C10—N4176.2 (2)
C2—C3—C4—C7174.8 (2)C8—C9—C10—N48.9 (4)
C3—C4—C5—C60.8 (4)O3—N4—C10—C9167.6 (2)
C7—C4—C5—C6174.3 (2)O2—N4—C10—C912.8 (4)
C4—C5—C6—C10.3 (4)O3—N4—C10—C1113.3 (3)
C2—C1—C6—C50.7 (4)O2—N4—C10—C11166.2 (2)
N1—C1—C6—C5179.2 (2)C9—C10—C11—C121.9 (4)
N3—N2—C7—O16.0 (3)N4—C10—C11—C12177.2 (2)
N3—N2—C7—C4170.59 (19)C10—C11—C12—C130.5 (4)
C5—C4—C7—O122.4 (4)C11—C12—C13—C141.8 (4)
C3—C4—C7—O1152.4 (2)C12—C13—C14—C90.7 (4)
C5—C4—C7—N2161.0 (2)C10—C9—C14—C131.6 (4)
C3—C4—C7—N224.1 (3)C8—C9—C14—C13173.8 (2)
N2—N3—C8—C9175.25 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···N1i0.892.443.287 (4)162
N1—H1B···O1ii0.892.353.164 (3)153
N2—H2···O1iii0.862.132.843 (3)142
C2—H2A···O1ii0.932.563.329 (3)140
Symmetry codes: (i) x+3, y+1/2, z; (ii) x+1, y1, z; (iii) x, y1, z.

Experimental details

Crystal data
Chemical formulaC14H12N4O3
Mr284.28
Crystal system, space groupMonoclinic, P21
Temperature (K)296
a, b, c (Å)6.4594 (13), 4.5998 (13), 20.598 (5)
β (°) 95.08 (4)
V3)609.6 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.25 × 0.18 × 0.10
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.976, 0.989
No. of measured, independent and
observed [I > 2σ(I)] reflections
4632, 2710, 1516
Rint0.048
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.111, 1.05
No. of reflections2710
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.27, 0.22

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···N1i0.892.443.287 (4)162
N1—H1B···O1ii0.892.353.164 (3)153
N2—H2···O1iii0.862.132.843 (3)142
C2—H2A···O1ii0.932.563.329 (3)140
Symmetry codes: (i) x+3, y+1/2, z; (ii) x+1, y1, z; (iii) x, y1, z.
 

Acknowledgements

This work was supported by the Natural Science Foundation of Guangxi Province (grant No. 2011GXNSFB018023) and the Natural Science Foundation of the Education Bureau of Guangxi Province (grant No. 201106LX535). This work was also supported by the Program for Excellent Talents in Guangxi Higher Education Institutions and the Dean's project of Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology (grant No. K011).

References

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