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Acta Crystallogr Sect E Struct Rep Online. 2009 February 1; 65(Pt 2): o371.
Published online 2009 January 23. doi:  10.1107/S1600536809002244
PMCID: PMC2968355

N,N′-Bis[(E)-4-cyano­benzyl­idene]urea

Abstract

The mol­ecule of the title compound, C17H10N4O, has crystallographically imposed C 2 symmetry. The urea group and the benzene ring are nearly coplanar, the dihedral angle between them being 4.15 (7)°. The crystal packing is stabilized by aromatic π–π stacking inter­actions, with a centroid-to-centroid separation of 3.833 (4) Å.

Related literature

For a general background on the use of nitriles as starting materials, see: Íkizler & Sancak (1992 [triangle]). For the products of the condensation of urea with alkynes, see: Martínez-García et al. (2004 [triangle]).

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Object name is e-65-0o371-scheme1.jpg

Experimental

Crystal data

  • C17H10N4O
  • M r = 286.29
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0o371-efi2.jpg
  • a = 10.552 (4) Å
  • b = 11.687 (5) Å
  • c = 12.198 (3) Å
  • β = 99.94 (4)°
  • V = 1481.7 (9) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 291 (2) K
  • 0.36 × 0.30 × 0.28 mm

Data collection

  • Rigaku Mercury2 diffractometer
  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 [triangle]) T min = 0.96, T max = 0.98
  • 6461 measured reflections
  • 1423 independent reflections
  • 1107 reflections with I > 2σ(I)
  • R int = 0.041

Refinement

  • R[F 2 > 2σ(F 2)] = 0.072
  • wR(F 2) = 0.164
  • S = 1.06
  • 1423 reflections
  • 102 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.43 e Å−3
  • Δρmin = −0.27 e Å−3

Data collection: CrystalClear (Rigaku, 2005 [triangle]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809002244/rz2289sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809002244/rz2289Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank Jiangsu Planned Projects for Postdoctoral Research Funds (grant No. 0802003B) and Professor Dr Rengen Xiong.

supplementary crystallographic information

Comment

Nitriles are parent compounds for the preparation of various functional organic materials having imidazole, triazole, or thidiazole functionalities (Íkizler & Sancak, 1992). The Schiff-base compounds derived from the condensation of urea with alkynes are very few (Martínez-García et al., 2004) because of the low reactivity of the NH2 group of urea. Here we report the crystal structure of the title compound, which was obtained by the reaction of urea with 4-cyanobenzaldehyde in acetic acid with ammonium chloride as a catalyzer.

The molecule of the title compound (Fig. 1) possesses a crystallographically imposed C2 symmetry, with atoms C1 and O1 located on a two-fold axis. The urea group and the aromatic rings are nearly coplanar, forming a dihedral angle of 4.15 (7)°. In the crystal packing, molecules are linked along the a axis by aromatic π–π stacking interactions, with centroid-to-centroid separations of 3.833 (4) Å, perpendicular interplanar distances of 3.474 (4) Å and centroid–centroid offsets of 1.620 (3) Å.

Experimental

A mixture of 4-cyanobenzaldehyde (0.53 g, 4 mmol), urea (0.36 g, 6 mmol) and NH4Cl (0.10 g, 1.6 mmol) was heated with stirring at 100°C in 5 ml acetic acid for 5 h. After cooling, the reaction mixture was washed with cold water (3 × 50 ml) and the residue recrystallized from ethyl acetate/n-hexane (1:2 v/v) to afford the title compound (0.57 g, 50%). Single crystals suitable for X-ray structure analysis were obtained by the slow evaporation of an ethyl acetate solution in air.

Refinement

All H atoms were placed in calculated positions and refined using a riding model aproximation, with C—H = 0.93 Å and with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
The molecular structure of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Unlabelled atoms are related to the labelled atoms by (-x, y, 1/2 - z).

Crystal data

C17H10N4OF(000) = 592
Mr = 286.29Dx = 1.283 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1587 reflections
a = 10.552 (4) Åθ = 2.6–27.4°
b = 11.687 (5) ŵ = 0.08 mm1
c = 12.198 (3) ÅT = 291 K
β = 99.94 (4)°Block, yellow
V = 1481.7 (9) Å30.36 × 0.30 × 0.28 mm
Z = 4

Data collection

Rigaku Mercury2 diffractometer1423 independent reflections
Radiation source: fine-focus sealed tube1107 reflections with I > 2σ(I)
graphiteRint = 0.041
Detector resolution: 13.6612 pixels mm-1θmax = 26.0°, θmin = 2.9°
CCD profile fitting scansh = −12→12
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)k = −14→14
Tmin = 0.96, Tmax = 0.98l = −15→15
6461 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.072Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.164H-atom parameters constrained
S = 1.06w = 1/[σ2(Fo2) + (0.0535P)2 + 1.99P] where P = (Fo2 + 2Fc2)/3
1423 reflections(Δ/σ)max < 0.001
102 parametersΔρmax = 0.43 e Å3
1 restraintΔρmin = −0.27 e Å3

Special details

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

xyzUiso*/Ueq
C10.00000.1727 (3)0.25000.0459 (8)
C20.0655 (2)0.1864 (2)0.45184 (18)0.0476 (6)
H2A0.06450.10680.44910.057*
C30.1028 (2)0.2366 (2)0.56187 (18)0.0419 (6)
C40.1265 (2)0.1659 (2)0.65419 (19)0.0505 (6)
H4A0.11740.08720.64450.061*
C50.1636 (2)0.2094 (2)0.7610 (2)0.0526 (7)
H5A0.17900.16050.82200.063*
C60.1773 (2)0.3265 (2)0.77534 (19)0.0484 (6)
C70.2135 (3)0.3729 (2)0.8858 (2)0.0564 (7)
C80.1546 (2)0.3991 (2)0.6841 (2)0.0544 (7)
H8A0.16400.47770.69420.065*
C90.1181 (2)0.3551 (2)0.5786 (2)0.0525 (7)
H9A0.10340.40430.51790.063*
N10.0325 (2)0.2397 (2)0.35441 (17)0.0643 (7)
N20.2416 (3)0.4101 (2)0.9729 (2)0.0772 (8)
O10.00000.0683 (2)0.25000.0655 (8)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0458 (18)0.055 (2)0.0363 (17)0.0000.0039 (13)0.000
C20.0485 (13)0.0509 (14)0.0428 (12)−0.0062 (10)0.0065 (10)−0.0032 (9)
C30.0412 (12)0.0466 (13)0.0384 (12)−0.0019 (9)0.0081 (9)0.0009 (9)
C40.0628 (15)0.0472 (14)0.0412 (13)−0.0034 (11)0.0085 (10)−0.0011 (10)
C50.0608 (16)0.0575 (16)0.0394 (12)0.0015 (12)0.0087 (11)0.0065 (11)
C60.0449 (13)0.0595 (15)0.0404 (13)0.0016 (11)0.0058 (10)−0.0095 (11)
C70.0638 (16)0.0577 (16)0.0468 (15)0.0041 (12)0.0073 (12)−0.0036 (12)
C80.0626 (16)0.0484 (14)0.0509 (14)−0.0036 (11)0.0063 (11)−0.0025 (11)
C90.0604 (15)0.0522 (14)0.0435 (13)−0.0021 (12)0.0049 (11)0.0055 (11)
N10.0696 (15)0.0745 (17)0.0472 (12)0.0003 (12)0.0055 (10)0.0023 (10)
N20.106 (2)0.0707 (17)0.0511 (14)0.0061 (14)0.0034 (13)−0.0151 (12)
O10.098 (2)0.0506 (16)0.0442 (14)0.0000.0009 (13)0.000

Geometric parameters (Å, °)

C1—O11.221 (4)C4—H4A0.9300
C1—N11.484 (3)C5—C61.384 (4)
C1—N1i1.484 (3)C5—H5A0.9300
C2—N11.334 (3)C6—C81.387 (4)
C2—C31.455 (3)C6—C71.442 (3)
C2—H2A0.9300C7—N21.138 (3)
C3—C41.384 (3)C8—C91.377 (3)
C3—C91.405 (3)C8—H8A0.9300
C4—C51.390 (3)C9—H9A0.9300
O1—C1—N1121.83 (16)C6—C5—H5A120.5
O1—C1—N1i121.83 (16)C4—C5—H5A120.5
N1—C1—N1i116.3 (3)C5—C6—C8120.2 (2)
N1—C2—C3128.4 (2)C5—C6—C7119.7 (2)
N1—C2—H2A115.8C8—C6—C7120.1 (2)
C3—C2—H2A115.8N2—C7—C6179.5 (3)
C4—C3—C9118.0 (2)C9—C8—C6120.2 (2)
C4—C3—C2119.5 (2)C9—C8—H8A119.9
C9—C3—C2122.5 (2)C6—C8—H8A119.9
C3—C4—C5121.8 (2)C8—C9—C3120.7 (2)
C3—C4—H4A119.1C8—C9—H9A119.7
C5—C4—H4A119.1C3—C9—H9A119.7
C6—C5—C4119.1 (2)C2—N1—C1120.3 (3)

Symmetry codes: (i) −x, y, −z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2289).

References

  • Íkizler, A. A. & Sancak, K. (1992). Monatsh. Chem.123, 257–263.
  • Martínez-García, A., Ortiz, M., Martínez, R., Ortiz, P. & Reguera, E. (2004). Ind. Crops Prod.19, 99–106.
  • Rigaku (2005). CrystalClear Rigaku Corporation, Tokyo, Japan.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography