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

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ISSN: 2056-9890

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

aCollege of Chemistry & Pharmacy, Taizhou University, Taizhou Zhejiang 317000, People's Republic of China, and bDepartment of Chemistry, Liaoning Normal University, Dalian 116029, People's Republic of China
*Correspondence e-mail: liushiyong2010@yahoo.cn

(Received 7 June 2010; accepted 9 June 2010; online 16 June 2010)

In the title compound, C14H11N3O4, the two benzene rings form a dihedral angle of 45.3 (3)°. The nitro group is twisted out of the attached ring by a dihedral angle of 37.5 (3)°. In the crystal structure, mol­ecules are linked into a two-dimensional network parallel to (100) by O—H⋯O and N—H⋯O hydrogen bonds.

Related literature

For the medicinal applications of hydrazone compounds, see: Hillmer et al. (2010[Hillmer, A. S., Putcha, P., Levin, J., Hogen, T., Hyman, B. T., Kretzschmar, H., McLean, P. J. & Giese, A. (2010). Biochem. Biophys. Res. Commun. 391, 461-466.]); Zhu et al. (2009[Zhu, Q.-Y., Wei, Y.-J. & Wang, F.-W. (2009). Pol. J. Chem. 83, 1233-1240.]); Jimenez-Pulido et al. (2008[Jimenez-Pulido, S. B., Linares-Ordonez, F. M., Martinez-Martos, J. M., Moreno-Carretero, M. N., Quiros-Olozabal, M. & Ramirez-Exposito, M. J. (2008). J. Inorg. Biochem. 102, 1677-1683.]); Raj et al. (2007[Raj, K. K. V., Narayana, B., Ashalatha, B. V., Kumari, N. S. & Sarojini, B. K. (2007). Eur. J. Med. Chem. 42, 425-429.]); Zhong et al. (2007[Zhong, X., Wei, H.-L., Liu, W.-S., Wang, D.-Q. & Wang, X. (2007). Bioorg. Med. Chem. Lett. 17, 3774-3777.]). For the crystal structures of hydrazones, see: Khaledi et al. (2009[Khaledi, H., Saharin, S. M., Mohd Ali, H., Robinson, W. T. & Abdulla, M. A. (2009). Acta Cryst. E65, o1920.]); Warad et al. (2009[Warad, I., Al-Nuri, M., Al-Resayes, S., Al-Farhan, K. & Ghazzali, M. (2009). Acta Cryst. E65, o1597.]); Back et al. (2009[Back, D. F., Ballin, M. A. & de Oliveira, G. M. (2009). J. Mol. Struct. 935, 151-155.]); Vijayakumar et al. (2009[Vijayakumar, S., Adhikari, A., Kalluraya, B. & Chandrasekharan, K. (2009). Opt. Mater. 31, 1564-1569.]). For related structures, see: Cao (2009[Cao, G.-B. (2009). Acta Cryst. E65, o2086.]); Xu et al. (2009[Xu, L., Huang, S.-S., Zhang, B.-J., Wang, S.-Y. & Zhang, H.-L. (2009). Acta Cryst. E65, o2412.]); Shafiq et al. (2009[Shafiq, Z., Yaqub, M., Tahir, M. N., Hussain, A. & Iqbal, M. S. (2009). Acta Cryst. E65, o2898.]).

[Scheme 1]

Experimental

Crystal data
  • C14H11N3O4

  • Mr = 285.26

  • Orthorhombic, P 21 21 21

  • a = 7.720 (2) Å

  • b = 11.398 (3) Å

  • c = 15.072 (5) Å

  • V = 1326.3 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 298 K

  • 0.20 × 0.18 × 0.18 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.979, Tmax = 0.981

  • 7745 measured reflections

  • 1602 independent reflections

  • 961 reflections with I > 2σ(I)

  • Rint = 0.085

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.125

  • S = 1.02

  • 1602 reflections

  • 194 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯O2i 0.82 1.93 2.725 (3) 164
N2—H2A⋯O1ii 0.90 (1) 2.05 (2) 2.932 (4) 166 (4)
Symmetry codes: (i) [-x, y-{\script{1\over 2}}, -z+{\script{5\over 2}}]; (ii) [-x+{\script{1\over 2}}, -y+1, z-{\script{1\over 2}}].

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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Considerable attention has been focused on hydrazones and their medicinal applications (Hillmer et al., 2010; Zhu et al., 2009; Jimenez-Pulido et al., 2008; Raj et al., 2007; Zhong et al., 2007). The study on the crystal structures of such compounds is of particular interest (Khaledi et al., 2009; Warad et al., 2009; Back et al., 2009; Vijayakumar et al., 2009). We report herein the crystal structure of the title new hydrazone.

In the title molecule (Fig. 1), the dihedral angle between the two benzene rings is 45.3 (3)°, indicating that the molecule is twisted. The dihedral angle between the N3/O3/O4 nitro group and the C9–C14 benzene ring is 37.5 (3)°. All the bond lengths are comparable to those observed in related structures (Cao, 2009; Xu et al., 2009; Shafiq et al., 2009).

In the crystal structure, molecules are linked through O—H···O and N—H···O hydrogen bonds, to form a two-dimensional network parallel to the (100) (Fig. 2 and Table 1).

Related literature top

For the medicinal applications of hydrazone compounds, see: Hillmer et al. (2010); Zhu et al. (2009); Jimenez-Pulido et al. (2008); Raj et al. (2007); Zhong et al. (2007). For the crystal structures of hydrazones, see: Khaledi et al. (2009); Warad et al. (2009); Back et al. (2009); Vijayakumar et al. (2009). For related structures, see: Cao (2009); Xu et al. (2009); Shafiq et al. (2009).

Experimental top

The title compound was prepared by the condensation reaction of 4-hydroxybenzaldehyde (0.05 mol, 6 g) and 2-nitrobenzohydrazide (0.05 mol, 9 g) in anhydrous methanol (200 ml) at ambient temperature. Colourless block-shaped single crystals suitable for X-ray structure determination were obtained by slow evaporation of the methanol solution for a period of 8 d.

Refinement top

Atom H2A was located in a difference map and refined isotropically, with the N–H distance restrained to 0.90 (1) Å [Uiso(H2) = 0.08 Å2]. The remaining H atoms were placed in idealized positions and constrained to ride on their parent atoms, with C–H distances of 0.93 Å, O–H distance of 0.82 Å, and with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(O). In the absence of significant anomalous dispersion effects, Friedel pairs were averaged.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (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. Displacement ellipsoids are drawn at the 30% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.
[Figure 2] Fig. 2. The molecular packing of the title compound, viewed along the a axis. Hydrogen bonds are shown as dashed lines. Hydrogen atoms not involved in hydrogen bonding have been omitted.
(E)-N'-(4-Hydroxybenzylidene)-2-nitrobenzohydrazide top
Crystal data top
C14H11N3O4F(000) = 592
Mr = 285.26Dx = 1.429 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 633 reflections
a = 7.720 (2) Åθ = 2.5–24.5°
b = 11.398 (3) ŵ = 0.11 mm1
c = 15.072 (5) ÅT = 298 K
V = 1326.3 (7) Å3Block, colourless
Z = 40.20 × 0.18 × 0.18 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
1602 independent reflections
Radiation source: fine-focus sealed tube961 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.085
ω scansθmax = 26.6°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 89
Tmin = 0.979, Tmax = 0.981k = 1413
7745 measured reflectionsl = 1818
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.02 w = 1/[σ2(Fo2) + (0.0542P)2]
where P = (Fo2 + 2Fc2)/3
1602 reflections(Δ/σ)max = 0.001
194 parametersΔρmax = 0.25 e Å3
1 restraintΔρmin = 0.18 e Å3
Crystal data top
C14H11N3O4V = 1326.3 (7) Å3
Mr = 285.26Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.720 (2) ŵ = 0.11 mm1
b = 11.398 (3) ÅT = 298 K
c = 15.072 (5) Å0.20 × 0.18 × 0.18 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
1602 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
961 reflections with I > 2σ(I)
Tmin = 0.979, Tmax = 0.981Rint = 0.085
7745 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0481 restraint
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 0.25 e Å3
1602 reflectionsΔρmin = 0.18 e Å3
194 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
N10.1071 (5)0.7318 (3)1.03691 (19)0.0490 (10)
N20.1251 (5)0.7909 (3)0.9568 (2)0.0486 (9)
N30.2475 (6)1.1354 (4)0.9364 (3)0.0729 (13)
O10.1478 (4)0.3516 (2)1.34410 (16)0.0478 (8)
H10.08260.37841.38200.072*
O20.0109 (4)0.9556 (2)1.01482 (16)0.0498 (8)
O30.3197 (5)1.0807 (4)0.9939 (2)0.0846 (12)
O40.2255 (9)1.2411 (4)0.9389 (3)0.151 (2)
C10.1311 (5)0.5519 (3)1.1159 (2)0.0386 (9)
C20.0734 (5)0.5986 (3)1.1956 (2)0.0415 (10)
H20.03060.67491.19710.050*
C30.0787 (5)0.5334 (3)1.2728 (3)0.0411 (10)
H30.04180.56571.32620.049*
C40.1396 (5)0.4197 (3)1.2695 (2)0.0362 (9)
C50.1956 (5)0.3714 (3)1.1908 (3)0.0428 (10)
H50.23670.29481.18920.051*
C60.1902 (5)0.4375 (3)1.1148 (2)0.0428 (10)
H60.22710.40471.06160.051*
C70.1348 (6)0.6220 (4)1.0351 (2)0.0452 (10)
H70.15790.58560.98120.054*
C80.0819 (5)0.9035 (3)0.9539 (2)0.0406 (10)
C90.1145 (5)0.9615 (3)0.8660 (2)0.0385 (9)
C100.1817 (6)1.0730 (4)0.8584 (3)0.0470 (11)
C110.1996 (6)1.1296 (4)0.7788 (3)0.0570 (12)
H110.24461.20520.77620.068*
C120.1495 (7)1.0721 (5)0.7024 (3)0.0649 (14)
H120.16181.10880.64770.078*
C130.0821 (6)0.9617 (4)0.7068 (3)0.0609 (13)
H130.04950.92280.65520.073*
C140.0624 (5)0.9078 (4)0.7889 (2)0.0468 (11)
H140.01270.83360.79170.056*
H2A0.189 (5)0.755 (4)0.915 (2)0.080*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.076 (3)0.0396 (19)0.0313 (18)0.0082 (19)0.0090 (19)0.0098 (15)
N20.073 (3)0.040 (2)0.0327 (19)0.008 (2)0.016 (2)0.0108 (15)
N30.095 (4)0.056 (3)0.067 (3)0.013 (3)0.011 (3)0.006 (2)
O10.065 (2)0.0454 (16)0.0334 (15)0.0081 (15)0.0097 (14)0.0069 (12)
O20.068 (2)0.0442 (16)0.0377 (15)0.0063 (16)0.0144 (15)0.0023 (13)
O30.087 (3)0.112 (3)0.055 (2)0.020 (3)0.0063 (19)0.009 (2)
O40.262 (7)0.056 (3)0.133 (4)0.013 (3)0.004 (4)0.027 (3)
C10.049 (2)0.033 (2)0.034 (2)0.001 (2)0.0034 (19)0.0029 (16)
C20.055 (3)0.035 (2)0.034 (2)0.006 (2)0.0031 (19)0.0018 (17)
C30.051 (3)0.041 (2)0.032 (2)0.002 (2)0.0087 (18)0.0002 (18)
C40.041 (2)0.038 (2)0.0303 (19)0.007 (2)0.0019 (18)0.0099 (17)
C50.057 (3)0.031 (2)0.041 (2)0.002 (2)0.001 (2)0.0005 (18)
C60.056 (3)0.041 (2)0.032 (2)0.000 (2)0.0040 (18)0.0034 (18)
C70.059 (3)0.046 (2)0.031 (2)0.003 (2)0.005 (2)0.0022 (17)
C80.050 (3)0.039 (2)0.033 (2)0.001 (2)0.0062 (19)0.0045 (18)
C90.047 (2)0.034 (2)0.034 (2)0.009 (2)0.0043 (19)0.0001 (17)
C100.053 (3)0.044 (2)0.043 (2)0.008 (2)0.008 (2)0.001 (2)
C110.060 (3)0.045 (3)0.067 (3)0.003 (2)0.013 (2)0.019 (2)
C120.073 (3)0.072 (3)0.049 (3)0.017 (3)0.011 (3)0.030 (3)
C130.073 (3)0.074 (3)0.036 (3)0.013 (3)0.000 (2)0.004 (2)
C140.056 (3)0.045 (2)0.039 (2)0.003 (2)0.0006 (19)0.0037 (19)
Geometric parameters (Å, º) top
N1—C71.270 (4)C4—C51.377 (5)
N1—N21.389 (4)C5—C61.372 (5)
N2—C81.327 (5)C5—H50.93
N2—H2A0.90 (1)C6—H60.93
N3—O31.204 (5)C7—H70.93
N3—O41.217 (5)C8—C91.501 (5)
N3—C101.466 (6)C9—C141.374 (5)
O1—C41.368 (4)C9—C101.377 (5)
O1—H10.82C10—C111.369 (5)
O2—C81.224 (4)C11—C121.379 (6)
C1—C61.381 (5)C11—H110.93
C1—C21.388 (5)C12—C131.363 (7)
C1—C71.457 (5)C12—H120.93
C2—C31.381 (5)C13—C141.390 (5)
C2—H20.93C13—H130.93
C3—C41.380 (5)C14—H140.93
C3—H30.93
C7—N1—N2116.2 (3)C1—C6—H6119.4
C8—N2—N1118.2 (3)N1—C7—C1121.3 (3)
C8—N2—H2A123 (3)N1—C7—H7119.3
N1—N2—H2A117 (3)C1—C7—H7119.3
O3—N3—O4123.7 (5)O2—C8—N2123.9 (3)
O3—N3—C10119.1 (4)O2—C8—C9121.5 (3)
O4—N3—C10117.2 (5)N2—C8—C9114.4 (3)
C4—O1—H1109.5C14—C9—C10116.8 (4)
C6—C1—C2118.6 (3)C14—C9—C8120.0 (4)
C6—C1—C7120.1 (3)C10—C9—C8123.0 (3)
C2—C1—C7121.3 (3)C11—C10—C9123.2 (4)
C3—C2—C1120.9 (3)C11—C10—N3116.0 (4)
C3—C2—H2119.6C9—C10—N3120.7 (4)
C1—C2—H2119.6C10—C11—C12118.6 (4)
C4—C3—C2119.0 (3)C10—C11—H11120.7
C4—C3—H3120.5C12—C11—H11120.7
C2—C3—H3120.5C13—C12—C11120.4 (4)
O1—C4—C5117.8 (3)C13—C12—H12119.8
O1—C4—C3121.3 (3)C11—C12—H12119.8
C5—C4—C3120.9 (3)C12—C13—C14119.5 (4)
C6—C5—C4119.4 (3)C12—C13—H13120.2
C6—C5—H5120.3C14—C13—H13120.2
C4—C5—H5120.3C9—C14—C13121.6 (4)
C5—C6—C1121.2 (4)C9—C14—H14119.2
C5—C6—H6119.4C13—C14—H14119.2
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.821.932.725 (3)164
N2—H2A···O1ii0.90 (1)2.05 (2)2.932 (4)166 (4)
Symmetry codes: (i) x, y1/2, z+5/2; (ii) x+1/2, y+1, z1/2.

Experimental details

Crystal data
Chemical formulaC14H11N3O4
Mr285.26
Crystal system, space groupOrthorhombic, P212121
Temperature (K)298
a, b, c (Å)7.720 (2), 11.398 (3), 15.072 (5)
V3)1326.3 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.20 × 0.18 × 0.18
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.979, 0.981
No. of measured, independent and
observed [I > 2σ(I)] reflections
7745, 1602, 961
Rint0.085
(sin θ/λ)max1)0.630
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.125, 1.02
No. of reflections1602
No. of parameters194
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.25, 0.18

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

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.821.932.725 (3)164
N2—H2A···O1ii0.90 (1)2.05 (2)2.932 (4)166 (4)
Symmetry codes: (i) x, y1/2, z+5/2; (ii) x+1/2, y+1, z1/2.
 

Acknowledgements

The authors acknowledge Taizhou University for financial support.

References

First citationBack, D. F., Ballin, M. A. & de Oliveira, G. M. (2009). J. Mol. Struct. 935, 151–155.  Web of Science CSD CrossRef CAS Google Scholar
First citationBruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationCao, G.-B. (2009). Acta Cryst. E65, o2086.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationHillmer, A. S., Putcha, P., Levin, J., Hogen, T., Hyman, B. T., Kretzschmar, H., McLean, P. J. & Giese, A. (2010). Biochem. Biophys. Res. Commun. 391, 461–466.  Web of Science CrossRef PubMed CAS Google Scholar
First citationJimenez-Pulido, S. B., Linares-Ordonez, F. M., Martinez-Martos, J. M., Moreno-Carretero, M. N., Quiros-Olozabal, M. & Ramirez-Exposito, M. J. (2008). J. Inorg. Biochem. 102, 1677–1683.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationKhaledi, H., Saharin, S. M., Mohd Ali, H., Robinson, W. T. & Abdulla, M. A. (2009). Acta Cryst. E65, o1920.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationRaj, K. K. V., Narayana, B., Ashalatha, B. V., Kumari, N. S. & Sarojini, B. K. (2007). Eur. J. Med. Chem. 42, 425–429.  PubMed CAS Google Scholar
First citationShafiq, Z., Yaqub, M., Tahir, M. N., Hussain, A. & Iqbal, M. S. (2009). Acta Cryst. E65, o2898.  Web of Science CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationVijayakumar, S., Adhikari, A., Kalluraya, B. & Chandrasekharan, K. (2009). Opt. Mater. 31, 1564–1569.  Web of Science CrossRef CAS Google Scholar
First citationWarad, I., Al-Nuri, M., Al-Resayes, S., Al-Farhan, K. & Ghazzali, M. (2009). Acta Cryst. E65, o1597.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationXu, L., Huang, S.-S., Zhang, B.-J., Wang, S.-Y. & Zhang, H.-L. (2009). Acta Cryst. E65, o2412.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationZhong, X., Wei, H.-L., Liu, W.-S., Wang, D.-Q. & Wang, X. (2007). Bioorg. Med. Chem. Lett. 17, 3774–3777.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationZhu, Q.-Y., Wei, Y.-J. & Wang, F.-W. (2009). Pol. J. Chem. 83, 1233–1240.  CAS Google Scholar

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