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

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ISSN: 2056-9890

1,2-Bis(3-phen­­oxy­benzyl­­idene)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 24 November 2011; accepted 5 December 2011; online 10 December 2011)

Mol­ecules of the title compound, C26H20N2O2, reside on crystallographic centres of inversion located at the mid-point of the N—N bond. The benzyl­idene ring is essentially coplanar with the central hydrazine group, with an inter­planar angle of 4.5 (2)°, whereas the phenyl ring is oriented at 34.0 (3)° with respect to the mean plane of the central 1,2-dibenzyl­idenehydrazine group. In the crystal, C—H⋯π(arene)-ring inter­actions link mol­ecules about inversion centres.

Related literature

For the biological activity of Schiff bases, see: Aydogan et al. (2001[Aydogan, F., Ocal, N., Turgut, Z. & Yolacan, C. (2001). Bull. Korean Chem. Soc. 22, 476-480.]); Desai et al. (2001[Desai, S. B., Desai, P. B. & Desai, K. R. (2001). Heterocycl. Commun. 7, 83-90.]); El-masry et al. (2000[El-masry, A. H., Fahmy, H. H. & Abdelwahed, S. H. A. (2000). Molecules, 5, 1429-1438.]); Hodnett & Dunn (1970[Hodnett, E. M. & Dunn, W. J. (1970). J. Med. Chem. 13, 768-770.]); Kundu et al. (2005[Kundu, N., Chatterjee, P. B., Chaudhury, M. & Tiekink, E. R. T. (2005). Acta Cryst. E61, m1583-m1585.]); Pandeya et al. (1999[Pandeya, S. N., Sriram, D., Nath, G. & De Clercq, E. (1999). Farmaco, 54, 624-628.]); Singh & Dash (1988[Singh, W. M. & Dash, B. C. (1988). Pesticides, 22, 33-37.]); Taggi et al. (2002[Taggi, A. E., Hafez, A. M., Wack, H., Young, B., Ferraris, D. & Lectka, T. (2002). J. Am. Chem. Soc. 124, 6626-6635.]); Xu et al. (1997[Xu, Z., Thompson, L. K. & Miller, D. O. (1997). Inorg. Chem. 36, 3985-3995.]); For crystallography and coordination chemistry of compounds containing the azine functionality or a diimine linkage, see: Xu et al. (1997[Xu, Z., Thompson, L. K. & Miller, D. O. (1997). Inorg. Chem. 36, 3985-3995.]); Kundu et al. (2005[Kundu, N., Chatterjee, P. B., Chaudhury, M. & Tiekink, E. R. T. (2005). Acta Cryst. E61, m1583-m1585.]); For related structures, see: Liu et al. (2007[Liu, G., Xie, L., Wang, Y. & Wang, J.-D. (2007). Acta Cryst. E63, o2611.]); Odabaşoğlu et al. (2007[Odabaşoğlu, M., Büyükgüngör, O., Sunil, K. & Narayana, B. (2007). Acta Cryst. E63, o4145-o4146.]); Zhang & Zheng (2008[Zhang, C.-N. & Zheng, Y.-F. (2008). Acta Cryst. E64, o36.]); Zheng et al. (2005a[Zheng, P.-W., Wang, W. & Duan, X.-M. (2005a). Acta Cryst. E61, o3485-o3486.],b[Zheng, P.-W., Wang, W. & Duan, X.-M. (2005b). Acta Cryst. E61, o3020-o3021.]). For standard bond lengths, see Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C26H20N2O2

  • Mr = 392.44

  • Monoclinic, C 2/c

  • a = 23.6271 (16) Å

  • b = 11.2942 (6) Å

  • c = 8.2359 (7) Å

  • β = 109.538 (8)°

  • V = 2071.2 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 170 K

  • 0.44 × 0.20 × 0.06 mm

Data collection
  • Oxford Diffraction 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, England.]) Tmin = 0.966, Tmax = 0.995

  • 4228 measured reflections

  • 2341 independent reflections

  • 1643 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.144

  • S = 1.05

  • 2341 reflections

  • 136 parameters

  • H-atom parameters constrained

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C7–C12 benzyl­idene ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5ACgi 0.93 2.68 3.5947 (17) 167
Symmetry code: (i) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z].

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

Schiff bases are known to exhibit biological activity such as antimicrobial (El-masry et al., 2000 & Pandeya et al., 1999), antifungal (Singh & Dash, 1988), antitumor (Hodnett & Dunn, 1970; Desai et al., 2001) and as herbicides. Moreover, Schiff bases are used as substrates in the preparation of number of industrial and biologically active compounds via ring closure, cycloaddition and replacement reactions. Schiff bases have also been employed as ligands for complexation of metal ions (Aydogan et al., 2001). On the industrial scale, they have wide range of applications such as dyes and pigments (Taggi et al., 2002). Compounds containing an azine functionality or a diimine linkage have been investigated in terms of their crystallography and coordination chemistry (Xu et al., 1997; Kundu et al., 2005).

The crystal structures of some Schiff base hydrazines, viz., 4-fluorobenzaldehyde[(E)-4-fluorobenzylidene]hydrazone (Odabaşoğlu et al., 2007), N,N'-bis(3-nitrobenzylidene)hydrazine (Zheng et al., 2005a), N,N'-Bis(4-chlorobenzylidene)hydrazine (Zheng et al., 2005b), 1,2-bis(2-chlorobenzylidene)hydrazine (Zhang & Zheng, 2008), N,N'-Bis(4-hydroxybenzylidene)hydrazine (Liu et al., 2007) have been reported. In view of the importance of Schiff base hydrazines, the crystal structure of title compound (I) is reported herein.

The complete molecule of the title compound, C26H20N2O2, is generated by the application of a centre of inversion (Fig. 1). The benzylidene ring is essentially coplanar with the central hydrazine group [dihedral angle = 4.5 (2)°] The dihedral angle between the mean plane of the 1,2-bis(benzylidene) hydrazine group and the two parallel phenyl rings is 34.0 (3)°. Weak C—H···Cg π-ring intermolecular interactions are observed (Table 1) providing some crystal packing stability (Fig. 2).

Related literature top

For the biological activity of Schiff bases, see: Aydogan et al. (2001); Desai et al. (2001); El-masry et al. (2000); Hodnett & Dunn (1970); Kundu et al. (2005) ; Pandeya et al. (1999); Singh & Dash (1988); Taggi et al. (2002); Xu et al. (1997); For crystallography and coordination chemistry of compounds containing the azine functionality or a diimine linkage, see: Xu et al. (1997); Kundu et al. (2005); For related structures, see: Liu et al. (2007); Odabaşoğlu et al. (2007); Zhang & Zheng (2008); Zheng et al. (2005a,b). For standard bond lengths, see Allen et al. (1987).

Experimental top

A mixture of 3-phenoxybenzaldehyde (0.02 mol) and hydrazine hydrate (0.012 mol) was refluxed in 15 ml of absolute alcohol containing 2 drops of sulfuric acid, for about 3 hours. On cooling, the resulting solid was filtered and dried. Single crystals were grown from DMF (dimethylformamide) by the slow evaporation method. Yield: 86%. (m.p.: 404 K).

Refinement top

All of the H atoms were placed in their calculated positions and then refined using the riding model with Atom—H lengths of 0.93Å (C–H). Isotropic displacement parameters for these atoms were set to 1.19-1.20 (CH) times Ueq of the parent atom.

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. Molecular structure of the title compound showing the atom labeling scheme and 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed along the c axis. The H atoms have been removed for clarity.
1,2-Bis(3-phenoxybenzylidene)hydrazine top
Crystal data top
C26H20N2O2F(000) = 824
Mr = 392.44Dx = 1.259 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1146 reflections
a = 23.6271 (16) Åθ = 3.1–28.6°
b = 11.2942 (6) ŵ = 0.08 mm1
c = 8.2359 (7) ÅT = 170 K
β = 109.538 (8)°Plate, yellow
V = 2071.2 (3) Å30.44 × 0.20 × 0.06 mm
Z = 4
Data collection top
Oxford Diffraction Xcalibur Eos Gemini
diffractometer
2341 independent reflections
Radiation source: Enhance (Mo) X-ray Source1643 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 16.1500 pixels mm-1θmax = 28.7°, θmin = 3.1°
ω scansh = 3119
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2010)
k = 1214
Tmin = 0.966, Tmax = 0.995l = 1010
4228 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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.144H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0591P)2 + 0.4457P]
where P = (Fo2 + 2Fc2)/3
2341 reflections(Δ/σ)max < 0.001
136 parametersΔρmax = 0.14 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C26H20N2O2V = 2071.2 (3) Å3
Mr = 392.44Z = 4
Monoclinic, C2/cMo Kα radiation
a = 23.6271 (16) ŵ = 0.08 mm1
b = 11.2942 (6) ÅT = 170 K
c = 8.2359 (7) Å0.44 × 0.20 × 0.06 mm
β = 109.538 (8)°
Data collection top
Oxford Diffraction Xcalibur Eos Gemini
diffractometer
2341 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2010)
1643 reflections with I > 2σ(I)
Tmin = 0.966, Tmax = 0.995Rint = 0.023
4228 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.144H-atom parameters constrained
S = 1.05Δρmax = 0.14 e Å3
2341 reflectionsΔρmin = 0.19 e Å3
136 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
O10.28415 (5)0.56492 (12)0.14723 (17)0.0634 (4)
N10.02329 (6)0.53855 (12)0.04610 (19)0.0533 (4)
C10.36654 (9)0.54126 (16)0.4051 (2)0.0582 (5)
H1B0.34670.47870.43610.070*
C20.42338 (10)0.5731 (2)0.5077 (3)0.0769 (7)
H2A0.44210.53210.60960.092*
C30.45254 (9)0.6644 (2)0.4612 (3)0.0818 (7)
H3A0.49110.68540.53100.098*
C40.42510 (10)0.7249 (2)0.3120 (3)0.0760 (7)
H4A0.44500.78700.28020.091*
C50.36825 (9)0.69433 (15)0.2091 (2)0.0584 (5)
H5A0.34930.73550.10760.070*
C60.33985 (7)0.60286 (14)0.2574 (2)0.0432 (4)
C70.23306 (7)0.60721 (15)0.1737 (2)0.0442 (4)
C80.23209 (7)0.70730 (14)0.2691 (2)0.0483 (4)
H8A0.26720.74970.32180.058*
C90.17840 (8)0.74360 (15)0.2851 (2)0.0491 (4)
H9A0.17760.81110.34910.059*
C100.12623 (7)0.68200 (14)0.2084 (2)0.0462 (4)
H10A0.09050.70710.22130.055*
C110.12717 (7)0.58123 (13)0.1108 (2)0.0416 (4)
C120.18101 (7)0.54480 (14)0.0936 (2)0.0441 (4)
H12A0.18200.47830.02810.053*
C130.07271 (7)0.51346 (15)0.0257 (2)0.0469 (4)
H13A0.07430.45040.04520.056*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0376 (6)0.0815 (9)0.0687 (9)0.0038 (6)0.0148 (6)0.0324 (7)
N10.0396 (8)0.0516 (9)0.0670 (10)0.0047 (6)0.0156 (7)0.0052 (7)
C10.0663 (12)0.0553 (11)0.0548 (11)0.0063 (9)0.0226 (9)0.0036 (9)
C20.0680 (14)0.0838 (16)0.0605 (13)0.0133 (13)0.0029 (11)0.0005 (11)
C30.0425 (11)0.0966 (18)0.0949 (18)0.0106 (12)0.0079 (11)0.0309 (15)
C40.0707 (14)0.0690 (14)0.0975 (18)0.0299 (12)0.0403 (14)0.0178 (13)
C50.0670 (12)0.0496 (10)0.0595 (11)0.0038 (9)0.0225 (10)0.0045 (9)
C60.0354 (8)0.0473 (9)0.0479 (9)0.0026 (7)0.0152 (7)0.0100 (7)
C70.0383 (8)0.0501 (9)0.0433 (9)0.0021 (7)0.0123 (7)0.0041 (7)
C80.0431 (9)0.0499 (10)0.0466 (9)0.0039 (8)0.0080 (7)0.0081 (8)
C90.0516 (10)0.0447 (9)0.0482 (10)0.0061 (8)0.0131 (8)0.0054 (8)
C100.0434 (9)0.0477 (9)0.0479 (9)0.0082 (7)0.0157 (7)0.0030 (7)
C110.0407 (8)0.0412 (9)0.0425 (9)0.0005 (7)0.0134 (7)0.0047 (7)
C120.0423 (9)0.0431 (9)0.0459 (9)0.0014 (7)0.0133 (7)0.0063 (7)
C130.0436 (9)0.0453 (9)0.0527 (10)0.0013 (7)0.0175 (8)0.0007 (8)
Geometric parameters (Å, º) top
O1—C71.3814 (18)C5—H5A0.9300
O1—C61.3930 (18)C7—C121.379 (2)
N1—C131.266 (2)C7—C81.381 (2)
N1—N1i1.410 (3)C8—C91.381 (2)
C1—C61.359 (2)C8—H8A0.9300
C1—C21.374 (3)C9—C101.372 (2)
C1—H1B0.9300C9—H9A0.9300
C2—C31.364 (3)C10—C111.398 (2)
C2—H2A0.9300C10—H10A0.9300
C3—C41.365 (3)C11—C121.388 (2)
C3—H3A0.9300C11—C131.459 (2)
C4—C51.371 (3)C12—H12A0.9300
C4—H4A0.9300C13—H13A0.9300
C5—C61.362 (2)
C7—O1—C6118.43 (12)C12—C7—O1115.75 (14)
C13—N1—N1i112.25 (17)C8—C7—O1123.66 (14)
C6—C1—C2118.82 (18)C9—C8—C7119.21 (15)
C6—C1—H1B120.6C9—C8—H8A120.4
C2—C1—H1B120.6C7—C8—H8A120.4
C3—C2—C1120.4 (2)C10—C9—C8121.21 (15)
C3—C2—H2A119.8C10—C9—H9A119.4
C1—C2—H2A119.8C8—C9—H9A119.4
C2—C3—C4119.92 (19)C9—C10—C11119.53 (15)
C2—C3—H3A120.0C9—C10—H10A120.2
C4—C3—H3A120.0C11—C10—H10A120.2
C3—C4—C5120.2 (2)C12—C11—C10119.42 (14)
C3—C4—H4A119.9C12—C11—C13119.11 (14)
C5—C4—H4A119.9C10—C11—C13121.47 (14)
C6—C5—C4119.14 (19)C7—C12—C11120.06 (15)
C6—C5—H5A120.4C7—C12—H12A120.0
C4—C5—H5A120.4C11—C12—H12A120.0
C1—C6—C5121.55 (17)N1—C13—C11121.53 (15)
C1—C6—O1118.67 (15)N1—C13—H13A119.2
C5—C6—O1119.58 (16)C11—C13—H13A119.2
C12—C7—C8120.56 (15)
C6—C1—C2—C30.5 (3)O1—C7—C8—C9178.76 (16)
C1—C2—C3—C40.2 (3)C7—C8—C9—C100.1 (3)
C2—C3—C4—C50.1 (3)C8—C9—C10—C110.6 (2)
C3—C4—C5—C60.2 (3)C9—C10—C11—C120.3 (2)
C2—C1—C6—C50.4 (3)C9—C10—C11—C13179.48 (15)
C2—C1—C6—O1175.27 (16)C8—C7—C12—C111.1 (3)
C4—C5—C6—C10.0 (3)O1—C7—C12—C11179.24 (14)
C4—C5—C6—O1174.87 (16)C10—C11—C12—C70.5 (2)
C7—O1—C6—C188.2 (2)C13—C11—C12—C7179.68 (14)
C7—O1—C6—C596.80 (19)N1i—N1—C13—C11179.40 (15)
C6—O1—C7—C12163.42 (14)C12—C11—C13—N1175.49 (16)
C6—O1—C7—C818.5 (2)C10—C11—C13—N14.7 (3)
C12—C7—C8—C90.7 (3)
Symmetry code: (i) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C7–C12 benzylidene ring.
D—H···AD—HH···AD···AD—H···A
C5—H5A···Cgii0.932.683.5947 (17)167
Symmetry code: (ii) x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC26H20N2O2
Mr392.44
Crystal system, space groupMonoclinic, C2/c
Temperature (K)170
a, b, c (Å)23.6271 (16), 11.2942 (6), 8.2359 (7)
β (°) 109.538 (8)
V3)2071.2 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.44 × 0.20 × 0.06
Data collection
DiffractometerOxford Diffraction Xcalibur Eos Gemini
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2010)
Tmin, Tmax0.966, 0.995
No. of measured, independent and
observed [I > 2σ(I)] reflections
4228, 2341, 1643
Rint0.023
(sin θ/λ)max1)0.675
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.144, 1.05
No. of reflections2341
No. of parameters136
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.14, 0.19

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

Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C7–C12 benzylidene ring.
D—H···AD—HH···AD···AD—H···A
C5—H5A···Cgi0.932.683.5947 (17)167
Symmetry code: (i) x+1/2, y+1/2, z.
 

Acknowledgements

ASP thanks the University of Mysore for research facilities. JPJ acknowledges the NSF–MRI program (grant No. CHE1039027) for funds to purchase the X-ray diffractometer.

References

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