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

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ISSN: 2056-9890

(1E,2E)-1,2-Bis(3-bromo-4-meth­­oxy­benzyl­­idene)hydrazine

aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, bDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, and cDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India
*Correspondence e-mail: jjasinski@keene.edu

(Received 3 May 2011; accepted 4 May 2011; online 11 May 2011)

In the title compound, C16H14Br2N2O2, the dihedral angle between the mean planes of the two benzene rings is 33.4 (2)°. The hydrazine group is twisted slightly, with C—N—N—C and C—C—N—N torsion angles of 167.5 (4) and 177.2 (4)/174.2 (4)°, respectively.

Related literature

For anti­tubercular behaviour in isonicotinoyl hydrazones, see: Kucukguzel et al. (1999[Kucukguzel, S. G., Rollas, S., Kucukguzel, I. & Kiraz, M. (1999). Eur. J. Med. Chem. 34, 1093-1100.]); Rollas et al. (2002[Rollas, S., Gulerman, N. & Erdeniz, H. (2002). Il Farmaco, 57, 171-174.]). For the coordination chemistry of azine compounds containing both a diamine linkage and an N—N bond, see: Armstrong et al. (1998[Armstrong, J. A., Barnes, J. C. & Weakley, T. J. R. (1998). Acta Cryst. C54, 1923-1925.]); Kesslen & Euler (1999[Kesslen, E. C. & Euler, W. B. (1999). Chem. Mater. 11, 336-340.]); Kundu et al. (2005[Kundu, N., Chatterjee, P. B., Chaudhury, M. & Tiekink, E. R. T. (2005). Acta Cryst. E61, m1583-m1585.]); Xu et al. (1997[Xu, Z., Thompson, L. K. & Miller, D. O. (1997). Inorg. Chem. 36, 3985-3995.]). For related structures, see: Zheng et al. (2005[Zheng, P.-W., Wang, W. & Duan, X.-M. (2005). Acta Cryst. E61, o3485-o3486.], 2006[Zheng, P.-W., Qiu, Q.-M., Lin, Y.-Y. & Liu, K.-F. (2006). Acta Cryst. E62, o1913-o1914.]); Zheng & Zhao (2006[Zheng, P.-W. & Zhao, B. (2006). Acta Cryst. E62, o2077-o2078.]); Odabaşoğlu et al. (2007[Odabaşoğlu, M., Büyükgüngör, O., Sunil, K. & Narayana, B. (2007). Acta Cryst. E63, o4145-o4146.]).

[Scheme 1]

Experimental

Crystal data
  • C16H14Br2N2O2

  • Mr = 426.11

  • Monoclinic, P 21 /c

  • a = 10.1354 (8) Å

  • b = 10.550 (1) Å

  • c = 15.6055 (12) Å

  • β = 96.680 (7)°

  • V = 1657.3 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.90 mm−1

  • T = 173 K

  • 0.20 × 0.15 × 0.10 mm

Data collection
  • Oxford Xcalibur Eos Gemini diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]) Tmin = 0.441, Tmax = 0.640

  • 14411 measured reflections

  • 3941 independent reflections

  • 2537 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.053

  • wR(F2) = 0.120

  • S = 1.09

  • 3941 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.53 e Å−3

  • Δρmin = −0.64 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis RED (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]); 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

Hydrazones are known to possess antimicrobial, anticonvulsant, analgesic, anti-inflammatory, antiplatelet, antitubercular and antitumoral activities. For example, isonicotinoyl hydrazones are antitubercular; 4-fluorobenzoic acid [(5-nitro-2-furyl)methylene]-hydrazide (Rollas et al., 2002) and 2,3,4-pentanetrione-3-[4-[[(5-nitro-2-furyl)methylene]hydrazine] carbonyl]phenyl]hydrazone (Kucukguzel et al., 1999) have antibacterial activity. A number of azine compounds containing both a diamine linkage and an N—N bond have been investigated in terms of their crystallography and coordination chemistry (Kundu et al., 2005; Kesslen & Euler, 1999; Armstrong et al., 1998; Xu et al., 1997). The crystal structures of N,N'-Bis(3-nitrobenzylidene)hydrazine (Zheng et al., 2005), N,N'-Bis(2,6-dichlorobenzylidene)hydrazine (Zheng et al., 2006), N,N'-Bis(9-anthracenylidene)hydrazine (Zheng & Zhao, 2006), 4-Fluorobenzaldehyde [(E)-4-fluorobenzylidene] hydrazone (Odabaşoğlu et al., 2007) have been reported. In view of the importance of hydrazones, the title compound, C16H14Br2N2O2, (I), is synthesized, Fig. 1, and its crystal structure is reported here.

In (I) the dihedral angle between the mean planes of the two benzene rings is 33.4 (2)° (Fig. 2). The hydrazine group is twisted slightly with C9—N1—N2—C10, N2—N1—C9—C5 and N1—N2—C10—C11 torsion angles of 167.5 (4) and 177.2 (4) and 174.2 (4)°, respectively. The crystal packing is stabilized by weak van der Waals interactions.

Related literature top

For antitubercular behaviour in isonicotinoyl hydrazones, see: Kucukguzel et al. (1999); Rollas et al. (2002). For coordination chemistry of azine compounds containing both a diamine linkage and an N—N bond, see: Armstrong et al. (1998); Kesslen & Euler (1999); Kundu et al. (2005); Xu et al. (1997). For related structures, see: Zheng et al. (2005, 2006); Zheng & Zhao (2006); Odabaşoğlu et al. (2007).

Experimental top

A mixture of 3-bromo-4-methoxy benzaldehyde (4.3 g, 0.02 mol) and hydrazine hydrate (0.5 ml, 0.01 mol) in 15 ml of ethanol containing 2 drops of 4 M sulfuric acid was refluxed for about 3 h (Fig. 1). On cooling, the solid separated, was filtered and recrystallized from N,N-dimethylformamide (m.p. 453–455 K).

Refinement top

The parameters of all the H atoms have been constrained within the riding atom approximation. C—H bond lengths were constrained to 0.95 Å for aryl atoms, Uiso(H) = 1.19–1.20Ueq(Caryl), and 0.98 Å for methyl atoms, Uiso(H) = 1.49Ueq(Cmethyl).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis RED (Oxford Diffraction, 2010); 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. Reaction scheme for the title compound.
[Figure 2] Fig. 2. Molecular structure of the title compound showing the atom labeling scheme and 50% probability displacement ellipsoids.
(1E,2E)-1,2-Bis(3-bromo-4-methoxybenzylidene)hydrazine top
Crystal data top
C16H14Br2N2O2F(000) = 840
Mr = 426.11Dx = 1.708 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3889 reflections
a = 10.1354 (8) Åθ = 3.0–32.2°
b = 10.550 (1) ŵ = 4.90 mm1
c = 15.6055 (12) ÅT = 173 K
β = 96.680 (7)°Block, yellow
V = 1657.3 (2) Å30.20 × 0.15 × 0.10 mm
Z = 4
Data collection top
Oxford Xcalibur Eos Gemini
diffractometer
3941 independent reflections
Radiation source: Enhance (Mo) X-ray Source2537 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.061
Detector resolution: 16.1500 pixels mm-1θmax = 27.9°, θmin = 3.0°
ω scansh = 1313
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2010)
k = 1313
Tmin = 0.441, Tmax = 0.640l = 2020
14411 measured reflections
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)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0419P)2 + 0.0769P]
where P = (Fo2 + 2Fc2)/3
3941 reflections(Δ/σ)max = 0.002
201 parametersΔρmax = 0.53 e Å3
0 restraintsΔρmin = 0.64 e Å3
Crystal data top
C16H14Br2N2O2V = 1657.3 (2) Å3
Mr = 426.11Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.1354 (8) ŵ = 4.90 mm1
b = 10.550 (1) ÅT = 173 K
c = 15.6055 (12) Å0.20 × 0.15 × 0.10 mm
β = 96.680 (7)°
Data collection top
Oxford Xcalibur Eos Gemini
diffractometer
3941 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2010)
2537 reflections with I > 2σ(I)
Tmin = 0.441, Tmax = 0.640Rint = 0.061
14411 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0530 restraints
wR(F2) = 0.120H-atom parameters constrained
S = 1.09Δρmax = 0.53 e Å3
3941 reflectionsΔρmin = 0.64 e Å3
201 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 > σ(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
Br10.58094 (5)0.79236 (5)1.06171 (3)0.06434 (19)
Br20.19292 (5)0.55086 (6)0.31176 (3)0.0745 (2)
O10.7706 (3)0.5773 (3)1.09367 (19)0.0569 (8)
O20.0712 (3)0.6690 (3)0.3128 (2)0.0651 (9)
N10.3700 (4)0.6100 (4)0.7479 (2)0.0593 (10)
N20.3124 (4)0.5901 (4)0.6626 (2)0.0564 (10)
C10.8682 (5)0.4829 (5)1.1222 (3)0.0741 (15)
H1B0.91520.50821.17810.111*
H1C0.93190.47501.07990.111*
H1D0.82410.40131.12830.111*
C20.6994 (4)0.5613 (4)1.0151 (3)0.0464 (10)
C30.6047 (4)0.6531 (4)0.9888 (3)0.0472 (10)
C40.5291 (4)0.6453 (4)0.9104 (3)0.0490 (10)
H4A0.46460.70880.89380.059*
C50.5461 (4)0.5448 (4)0.8545 (3)0.0498 (11)
C60.6410 (4)0.4535 (4)0.8803 (3)0.0531 (11)
H6A0.65390.38470.84290.064*
C70.7170 (4)0.4611 (5)0.9595 (3)0.0543 (12)
H7A0.78150.39770.97610.065*
C90.4677 (5)0.5372 (5)0.7703 (3)0.0547 (12)
H9A0.49050.47510.73050.066*
C100.2020 (5)0.6449 (5)0.6464 (3)0.0553 (11)
H10A0.16490.68600.69220.066*
C110.1288 (4)0.6482 (4)0.5605 (3)0.0482 (10)
C120.1842 (4)0.6029 (4)0.4883 (3)0.0502 (11)
H12A0.27010.56570.49530.060*
C130.1157 (4)0.6119 (4)0.4083 (3)0.0467 (10)
C140.0115 (4)0.6638 (4)0.3947 (3)0.0487 (10)
C150.0675 (4)0.7078 (5)0.4665 (3)0.0584 (12)
H15A0.15450.74270.45960.070*
C160.0030 (5)0.7007 (4)0.5478 (3)0.0575 (12)
H16A0.03580.73270.59590.069*
C170.2036 (5)0.7208 (5)0.2988 (3)0.0742 (15)
H17A0.23630.71630.23720.111*
H17B0.20200.80940.31770.111*
H17C0.26240.67180.33190.111*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0684 (3)0.0498 (3)0.0762 (4)0.0041 (2)0.0140 (2)0.0208 (2)
Br20.0810 (4)0.0889 (5)0.0578 (3)0.0361 (3)0.0266 (2)0.0049 (3)
O10.0587 (18)0.052 (2)0.0613 (19)0.0032 (15)0.0121 (15)0.0035 (15)
O20.0606 (19)0.068 (2)0.067 (2)0.0150 (17)0.0113 (15)0.0011 (17)
N10.069 (2)0.058 (3)0.053 (2)0.000 (2)0.0149 (18)0.0042 (19)
N20.068 (3)0.052 (3)0.052 (2)0.009 (2)0.0194 (18)0.0028 (18)
C10.071 (3)0.072 (4)0.080 (4)0.023 (3)0.010 (3)0.007 (3)
C20.049 (2)0.038 (3)0.056 (3)0.007 (2)0.024 (2)0.0015 (19)
C30.045 (2)0.037 (3)0.064 (3)0.0049 (19)0.027 (2)0.010 (2)
C40.044 (2)0.042 (3)0.065 (3)0.0026 (19)0.021 (2)0.004 (2)
C50.049 (2)0.046 (3)0.059 (3)0.011 (2)0.027 (2)0.008 (2)
C60.061 (3)0.042 (3)0.062 (3)0.000 (2)0.029 (2)0.007 (2)
C70.057 (3)0.047 (3)0.064 (3)0.008 (2)0.026 (2)0.003 (2)
C90.062 (3)0.051 (3)0.056 (3)0.013 (2)0.029 (2)0.007 (2)
C100.069 (3)0.043 (3)0.059 (3)0.008 (2)0.025 (2)0.007 (2)
C110.059 (3)0.034 (3)0.055 (3)0.002 (2)0.022 (2)0.0010 (19)
C120.053 (3)0.036 (3)0.065 (3)0.002 (2)0.022 (2)0.002 (2)
C130.052 (2)0.037 (3)0.055 (3)0.006 (2)0.019 (2)0.0032 (19)
C140.052 (2)0.037 (3)0.060 (3)0.002 (2)0.018 (2)0.002 (2)
C150.051 (3)0.046 (3)0.081 (3)0.006 (2)0.024 (2)0.001 (2)
C160.063 (3)0.044 (3)0.070 (3)0.000 (2)0.028 (2)0.012 (2)
C170.065 (3)0.074 (4)0.082 (4)0.019 (3)0.006 (3)0.001 (3)
Geometric parameters (Å, º) top
Br1—C31.891 (4)C6—C71.380 (6)
Br2—C131.889 (4)C6—H6A0.9500
O1—C21.359 (5)C7—H7A0.9500
O1—C11.437 (5)C9—H9A0.9500
O2—C141.351 (5)C10—C111.456 (6)
O2—C171.442 (5)C10—H10A0.9500
N1—C91.269 (6)C11—C161.383 (6)
N1—N21.405 (5)C11—C121.399 (5)
N2—C101.259 (6)C12—C131.361 (6)
C1—H1B0.9800C12—H12A0.9500
C1—H1C0.9800C13—C141.394 (6)
C1—H1D0.9800C14—C151.392 (6)
C2—C31.391 (6)C15—C161.383 (6)
C2—C71.393 (6)C15—H15A0.9500
C3—C41.369 (6)C16—H16A0.9500
C4—C51.396 (6)C17—H17A0.9800
C4—H4A0.9500C17—H17B0.9800
C5—C61.387 (6)C17—H17C0.9800
C5—C91.456 (6)
C2—O1—C1117.9 (4)N1—C9—H9A118.6
C14—O2—C17117.7 (4)C5—C9—H9A118.6
C9—N1—N2113.3 (4)N2—C10—C11122.8 (4)
C10—N2—N1112.5 (4)N2—C10—H10A118.6
O1—C1—H1B109.5C11—C10—H10A118.6
O1—C1—H1C109.5C16—C11—C12118.1 (4)
H1B—C1—H1C109.5C16—C11—C10120.3 (4)
O1—C1—H1D109.5C12—C11—C10121.5 (4)
H1B—C1—H1D109.5C13—C12—C11120.3 (4)
H1C—C1—H1D109.5C13—C12—H12A119.8
O1—C2—C3117.1 (4)C11—C12—H12A119.8
O1—C2—C7124.3 (4)C12—C13—C14122.1 (4)
C3—C2—C7118.6 (4)C12—C13—Br2119.6 (3)
C4—C3—C2121.1 (4)C14—C13—Br2118.4 (3)
C4—C3—Br1119.2 (3)O2—C14—C15124.7 (4)
C2—C3—Br1119.7 (3)O2—C14—C13117.6 (4)
C3—C4—C5120.5 (4)C15—C14—C13117.7 (4)
C3—C4—H4A119.8C16—C15—C14120.3 (4)
C5—C4—H4A119.8C16—C15—H15A119.9
C6—C5—C4118.5 (4)C14—C15—H15A119.9
C6—C5—C9120.7 (4)C11—C16—C15121.5 (4)
C4—C5—C9120.7 (4)C11—C16—H16A119.3
C7—C6—C5121.0 (4)C15—C16—H16A119.3
C7—C6—H6A119.5O2—C17—H17A109.5
C5—C6—H6A119.5O2—C17—H17B109.5
C6—C7—C2120.2 (4)H17A—C17—H17B109.5
C6—C7—H7A119.9O2—C17—H17C109.5
C2—C7—H7A119.9H17A—C17—H17C109.5
N1—C9—C5122.8 (4)H17B—C17—H17C109.5
C9—N1—N2—C10167.5 (4)N1—N2—C10—C11174.2 (4)
C1—O1—C2—C3179.5 (4)N2—C10—C11—C16174.6 (4)
C1—O1—C2—C71.6 (6)N2—C10—C11—C127.6 (7)
O1—C2—C3—C4179.5 (3)C16—C11—C12—C130.6 (7)
C7—C2—C3—C40.5 (6)C10—C11—C12—C13177.3 (4)
O1—C2—C3—Br10.3 (5)C11—C12—C13—C141.1 (7)
C7—C2—C3—Br1178.7 (3)C11—C12—C13—Br2179.7 (3)
C2—C3—C4—C50.4 (6)C17—O2—C14—C151.6 (7)
Br1—C3—C4—C5178.8 (3)C17—O2—C14—C13179.0 (4)
C3—C4—C5—C60.0 (6)C12—C13—C14—O2179.8 (4)
C3—C4—C5—C9178.9 (4)Br2—C13—C14—O21.0 (5)
C4—C5—C6—C70.2 (6)C12—C13—C14—C150.4 (7)
C9—C5—C6—C7179.1 (4)Br2—C13—C14—C15179.6 (3)
C5—C6—C7—C20.0 (6)O2—C14—C15—C16178.6 (4)
O1—C2—C7—C6179.2 (4)C13—C14—C15—C160.8 (7)
C3—C2—C7—C60.4 (6)C12—C11—C16—C150.6 (7)
N2—N1—C9—C5177.2 (4)C10—C11—C16—C15178.4 (4)
C6—C5—C9—N1171.8 (4)C14—C15—C16—C111.3 (7)
C4—C5—C9—N19.3 (6)

Experimental details

Crystal data
Chemical formulaC16H14Br2N2O2
Mr426.11
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)10.1354 (8), 10.550 (1), 15.6055 (12)
β (°) 96.680 (7)
V3)1657.3 (2)
Z4
Radiation typeMo Kα
µ (mm1)4.90
Crystal size (mm)0.20 × 0.15 × 0.10
Data collection
DiffractometerOxford Xcalibur Eos Gemini
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2010)
Tmin, Tmax0.441, 0.640
No. of measured, independent and
observed [I > 2σ(I)] reflections
14411, 3941, 2537
Rint0.061
(sin θ/λ)max1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.053, 0.120, 1.09
No. of reflections3941
No. of parameters201
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.53, 0.64

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), CrysAlis RED (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

CSC and HSY thank the University of Mysore for research facilities. JPJ acknowledges the NSF–MRI programme (grant No. CHE1039027) for funds to purchase the X-ray diffractometer.

References

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