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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o827
doi:10.1107/S1600536811008294

1,3-Di­ethyl-1,3-di­phenyl­urea

Richard Betz,a* Thomas Gerbera and Henk Schalekampa

aNelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth 6031, South Africa
*Correspondence e-mail: richard.betz@webmail.co.za

(Received 22 February 2011; accepted 4 March 2011; online 9 March 2011)

The mol­ecule of the title compound, C17H20N2O, a symmetrical derivative of urea, shows non-crystallographic C2 symmetry. Inter­action with the aromatic system of the phenyl substituents as well as amide-type resonance is responsible for the marked planarization of the coordination environments of the N atoms. C—H⋯O contacts give rise to the formation of centrosymmetric dimers in the crystal structure. The closest distance between the centroids of two adjacent rings is 3.8938 (11) Å.

Related literature

For the crystal structure of a uranium coordination compound with the title compound as a ligand, see: Zhu et al. (2008[Zhu, L.-M., Wang, L.-Y., Jin, J.-R., Li, B.-L. & Zhang, Y. (2008). J. Coord. Chem. 61, 917-925.]). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]); Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data

  • C17H20N2O

  • Mr = 268.35

  • Monoclinic, P 21 /c

  • a = 9.6990 (5) Å

  • b = 16.7622 (10) Å

  • c = 10.6011 (5) Å

  • β = 118.854 (4)°

  • V = 1509.52 (14) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 200 K

  • 0.44 × 0.27 × 0.20 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • 14247 measured reflections

  • 3723 independent reflections

  • 2926 reflections with I > 2σ(I)

  • Rint = 0.030
Refinement

  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.141

  • S = 1.04

  • 3723 reflections

  • 183 parameters

  • H-atom parameters constrained

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C13—H13⋯O1i 0.95 2.68 3.326 (2) 126
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2010[Bruker (2010). APEX2 and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2010[Bruker (2010). APEX2 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811008294/ez2237sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811008294/ez2237Isup2.hkl

checkCIF report


Comment top

Chelate ligands are an important class of molecules in coordination chemistry due to the increased thermodynamic stability of coordination compounds obtainable in comparison to those derived from monodentate ligands only. Derivatives of urea are of particular interest in this aspect due to a number of reasons: firstly, urea itself can act as a neutral or – upon deprotonation – anionic ligand. Secondly, apart from exclusive N-donor action, the carbonyl O-atom may serve as donor as well. Thirdly, the possible derivatization of the N-atoms allows for the fine-tuning of the nucleophilicity of these atoms, such that a vast series of different symmetric, as well as asymmetric, derivatives is at hand. A crystal structure of a uranium coordination compound utilising the title compound as ligand has been published (Zhu et al., 2008). At the beginning of a bigger study to elucidate the rules guiding the formation of urea-derivative-supported coordination compounds we determined the structure of the title compound to allow for comparisons with the ligand in such compounds.

In the molecule (Fig. 1), the coordination environment around both nitrogen atoms is almost planar due to the interaction of the free electron pair not only in terms of amide-type resonance but also with the phenyl-moiety. The N-atoms are displaced by only 0.183 (1) Å and -0.180 (1) Å from the planes defined by the atoms bonded to them.

The least-squares planes defined by the carbon atoms of the phenyl rings enclose an angle of 40.31 (4) °.

In the crystal structure, C–H···O contacts are present whose range falls sightly below the sum of van-der-Waals radii of the atoms involved. They involve one of the phenyl hydrogen atoms which is meta to the nitrogen atom and connect the molecules into centrosymmetric dimers (Fig. 2). In terms of graph-set analysis, the descriptor for these contacts on the unitary level is R22(14) (Etter et al., 1990; Bernstein et al., 1995). The closest distance between two centers of gravity was measured at 3.8938 (11) Å.

The packing of the title compound is shown in Fig. 3.

Related literature top

For the crystal structure of a uranium coordination compound applying the title compound as ligand, see: Zhu et al. (2008). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990); Bernstein et al. (1995).

Experimental top

The compound was obtained commercially (Aldrich). Crystals suitable for the X-ray diffraction study were taken directly from the provided compound.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.99 Å for methylene groups, C—H 0.95 Å for aromatic C-atoms) and were included in the refinement in the riding model approximation, with U(H) set to 1.2Ueq(C). The H atoms of the methyl groups were allowed to rotate with a fixed angle around the C—C bond to best fit the experimental electron density (HFIX 137 in the SHELX program suite (Sheldrick, 2008)), with U(H) set to 1.5Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level).
[Figure 2] Fig. 2. Intermolecular contacts, viewed approximately along [0 1 0]. Symmetry operator: i -x + 1, -y + 1, -z + 1.
[Figure 3] Fig. 3. Molecular packing of the title compound, viewed along [0 1 0] (anisotropic displacement ellipsoids drawn at 50% probability level).
1,3-Diethyl-1,3-diphenylurea top
Crystal data top
C17H20N2OF(000) = 576
Mr = 268.35Dx = 1.181 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6636 reflections
a = 9.6990 (5) Åθ = 2.5–28.2°
b = 16.7622 (10) ŵ = 0.07 mm−1
c = 10.6011 (5) ÅT = 200 K
β = 118.854 (4)°Platelet, colourless
V = 1509.52 (14) Å30.44 × 0.27 × 0.20 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer		2926 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.030
Graphite monochromatorθmax = 28.3°, θmin = 2.4°
ϕ and ω scansh = −12→8
14247 measured reflectionsk = −22→22
3723 independent reflectionsl = −13→14
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)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.141H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0689P)2 + 0.3719P]
where P = (Fo2 + 2Fc2)/3
3723 reflections(Δ/σ)max < 0.001
183 parametersΔρmax = 0.20 e Å−3
0 restraintsΔρmin = −0.22 e Å−3
Crystal data top
C17H20N2OV = 1509.52 (14) Å3
Mr = 268.35Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.6990 (5) ŵ = 0.07 mm−1
b = 16.7622 (10) ÅT = 200 K
c = 10.6011 (5) Å0.44 × 0.27 × 0.20 mm
β = 118.854 (4)°
Data collection top
Bruker APEXII CCD
diffractometer		2926 reflections with I > 2σ(I)
14247 measured reflectionsRint = 0.030
3723 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.141H-atom parameters constrained
S = 1.04Δρmax = 0.20 e Å−3
3723 reflectionsΔρmin = −0.22 e Å−3
183 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.27619 (13)0.58513 (6)0.22318 (11)0.0467 (3)
N10.31375 (13)0.45259 (7)0.20565 (11)0.0369 (3)
N20.16310 (13)0.49836 (7)0.31074 (11)0.0351 (3)
C10.25214 (15)0.51597 (8)0.24532 (13)0.0345 (3)
C20.39920 (18)0.47225 (10)0.12691 (15)0.0463 (4)
H2A0.35180.52050.06780.056*
H2B0.38680.42780.06070.056*
C30.5722 (2)0.48692 (15)0.2249 (2)0.0713 (6)
H3A0.58540.53100.29050.107*
H3B0.62270.50060.16710.107*
H3C0.62080.43860.28100.107*
C40.10811 (17)0.56703 (9)0.36121 (16)0.0421 (3)
H4A0.19060.60880.39750.050*
H4B0.09160.54990.44230.050*
C5−0.04350 (19)0.60209 (11)0.2438 (2)0.0592 (5)
H5A−0.02790.61920.16320.089*
H5B−0.07400.64810.28190.089*
H5C−0.12680.56170.21020.089*
C110.35486 (15)0.37776 (8)0.27978 (14)0.0352 (3)
C120.43976 (16)0.37458 (9)0.42910 (15)0.0395 (3)
H120.46580.42250.48380.047*
C130.48642 (18)0.30161 (10)0.49829 (18)0.0496 (4)
H130.54230.29940.60050.060*
C140.4519 (2)0.23230 (10)0.4191 (2)0.0580 (4)
H140.48540.18230.46660.070*
C150.3686 (2)0.23543 (10)0.2708 (2)0.0579 (4)
H150.34510.18750.21650.069*
C160.31902 (18)0.30777 (9)0.20057 (17)0.0469 (4)
H160.26060.30950.09840.056*
C210.07073 (15)0.42715 (8)0.28284 (14)0.0350 (3)
C220.07456 (17)0.38606 (9)0.39755 (16)0.0437 (3)
H220.14230.40330.49340.052*
C23−0.0204 (2)0.31984 (10)0.3726 (2)0.0557 (4)
H23−0.01780.29160.45140.067*
C24−0.1193 (2)0.29477 (10)0.2329 (2)0.0588 (5)
H24−0.18430.24920.21590.071*
C25−0.12340 (18)0.33586 (10)0.11852 (18)0.0531 (4)
H25−0.19110.31850.02280.064*
C26−0.02929 (16)0.40234 (9)0.14263 (15)0.0436 (3)
H26−0.03300.43090.06360.052*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0549 (6)0.0398 (6)0.0458 (6)−0.0044 (5)0.0245 (5)0.0027 (4)
N10.0368 (6)0.0425 (6)0.0333 (5)0.0007 (5)0.0185 (5)0.0019 (4)
N20.0330 (6)0.0350 (5)0.0370 (5)−0.0016 (4)0.0166 (5)−0.0042 (4)
C10.0307 (6)0.0398 (7)0.0275 (5)−0.0015 (5)0.0095 (5)−0.0001 (5)
C20.0504 (8)0.0574 (9)0.0387 (7)0.0007 (7)0.0274 (6)0.0046 (6)
C30.0507 (10)0.1048 (17)0.0672 (11)−0.0138 (10)0.0355 (9)0.0088 (11)
C40.0420 (7)0.0397 (7)0.0457 (7)0.0000 (6)0.0220 (6)−0.0079 (6)
C50.0423 (9)0.0490 (9)0.0782 (12)0.0073 (7)0.0227 (8)−0.0042 (8)
C110.0296 (6)0.0394 (7)0.0389 (7)−0.0010 (5)0.0182 (5)−0.0010 (5)
C120.0321 (6)0.0434 (7)0.0403 (7)0.0003 (5)0.0153 (5)−0.0004 (6)
C130.0378 (8)0.0569 (9)0.0506 (8)0.0054 (6)0.0187 (6)0.0144 (7)
C140.0532 (9)0.0419 (8)0.0867 (13)0.0050 (7)0.0399 (9)0.0157 (8)
C150.0627 (11)0.0393 (8)0.0792 (12)−0.0080 (7)0.0403 (10)−0.0095 (8)
C160.0466 (8)0.0465 (8)0.0491 (8)−0.0080 (6)0.0244 (7)−0.0091 (6)
C210.0280 (6)0.0362 (6)0.0396 (7)0.0003 (5)0.0152 (5)−0.0028 (5)
C220.0393 (7)0.0471 (8)0.0429 (7)−0.0026 (6)0.0184 (6)0.0012 (6)
C230.0511 (9)0.0507 (9)0.0676 (10)−0.0046 (7)0.0304 (8)0.0086 (8)
C240.0416 (8)0.0441 (9)0.0864 (13)−0.0099 (7)0.0274 (9)−0.0094 (8)
C250.0372 (8)0.0554 (9)0.0562 (9)−0.0066 (7)0.0141 (7)−0.0176 (8)
C260.0341 (7)0.0509 (8)0.0393 (7)−0.0012 (6)0.0125 (6)−0.0056 (6)
Geometric parameters (Å, º) top
O1—C11.2273 (16)C12—C131.385 (2)
N1—C11.3803 (17)C12—H120.9500
N1—C111.4310 (17)C13—C141.377 (3)
N1—C21.4697 (17)C13—H130.9500
N2—C11.3755 (18)C14—C151.379 (3)
N2—C211.4349 (17)C14—H140.9500
N2—C41.4734 (17)C15—C161.382 (2)
C2—C31.507 (2)C15—H150.9500
C2—H2A0.9900C16—H160.9500
C2—H2B0.9900C21—C221.382 (2)
C3—H3A0.9800C21—C261.3899 (19)
C3—H3B0.9800C22—C231.384 (2)
C3—H3C0.9800C22—H220.9500
C4—C51.514 (2)C23—C241.385 (3)
C4—H4A0.9900C23—H230.9500
C4—H4B0.9900C24—C251.378 (3)
C5—H5A0.9800C24—H240.9500
C5—H5B0.9800C25—C261.384 (2)
C5—H5C0.9800C25—H250.9500
C11—C161.3859 (19)C26—H260.9500
C11—C121.3887 (19)
C1—N1—C11123.66 (11)C12—C11—N1120.96 (12)
C1—N1—C2116.50 (12)C13—C12—C11120.00 (14)
C11—N1—C2115.12 (11)C13—C12—H12120.0
C1—N2—C21123.78 (11)C11—C12—H12120.0
C1—N2—C4116.15 (11)C14—C13—C12120.06 (15)
C21—N2—C4115.16 (11)C14—C13—H13120.0
O1—C1—N2121.51 (12)C12—C13—H13120.0
O1—C1—N1121.23 (12)C13—C14—C15119.97 (15)
N2—C1—N1117.25 (11)C13—C14—H14120.0
N1—C2—C3112.95 (12)C15—C14—H14120.0
N1—C2—H2A109.0C14—C15—C16120.51 (15)
C3—C2—H2A109.0C14—C15—H15119.7
N1—C2—H2B109.0C16—C15—H15119.7
C3—C2—H2B109.0C15—C16—C11119.73 (15)
H2A—C2—H2B107.8C15—C16—H16120.1
C2—C3—H3A109.5C11—C16—H16120.1
C2—C3—H3B109.5C22—C21—C26120.02 (13)
H3A—C3—H3B109.5C22—C21—N2118.95 (12)
C2—C3—H3C109.5C26—C21—N2120.90 (13)
H3A—C3—H3C109.5C21—C22—C23119.91 (14)
H3B—C3—H3C109.5C21—C22—H22120.0
N2—C4—C5112.51 (12)C23—C22—H22120.0
N2—C4—H4A109.1C22—C23—C24120.08 (16)
C5—C4—H4A109.1C22—C23—H23120.0
N2—C4—H4B109.1C24—C23—H23120.0
C5—C4—H4B109.1C25—C24—C23120.01 (15)
H4A—C4—H4B107.8C25—C24—H24120.0
C4—C5—H5A109.5C23—C24—H24120.0
C4—C5—H5B109.5C24—C25—C26120.23 (15)
H5A—C5—H5B109.5C24—C25—H25119.9
C4—C5—H5C109.5C26—C25—H25119.9
H5A—C5—H5C109.5C25—C26—C21119.75 (15)
H5B—C5—H5C109.5C25—C26—H26120.1
C16—C11—C12119.71 (13)C21—C26—H26120.1
C16—C11—N1119.17 (12)
C21—N2—C1—O1149.90 (12)C11—C12—C13—C141.5 (2)
C4—N2—C1—O1−4.06 (18)C12—C13—C14—C15−1.0 (2)
C21—N2—C1—N1−30.20 (17)C13—C14—C15—C16−0.1 (3)
C4—N2—C1—N1175.84 (11)C14—C15—C16—C110.7 (2)
C11—N1—C1—O1150.16 (13)C12—C11—C16—C15−0.3 (2)
C2—N1—C1—O1−4.23 (18)N1—C11—C16—C15175.11 (14)
C11—N1—C1—N2−29.74 (17)C1—N2—C21—C22136.14 (14)
C2—N1—C1—N2175.87 (11)C4—N2—C21—C22−69.67 (16)
C1—N1—C2—C389.43 (18)C1—N2—C21—C26−48.07 (18)
C11—N1—C2—C3−67.16 (19)C4—N2—C21—C26106.12 (15)
C1—N2—C4—C585.17 (16)C26—C21—C22—C230.5 (2)
C21—N2—C4—C5−71.05 (16)N2—C21—C22—C23176.32 (13)
C1—N1—C11—C16138.84 (14)C21—C22—C23—C240.0 (2)
C2—N1—C11—C16−66.45 (16)C22—C23—C24—C25−0.1 (3)
C1—N1—C11—C12−45.86 (18)C23—C24—C25—C26−0.2 (3)
C2—N1—C11—C12108.86 (15)C24—C25—C26—C210.6 (2)
C16—C11—C12—C13−0.9 (2)C22—C21—C26—C25−0.8 (2)
N1—C11—C12—C13−176.13 (13)N2—C21—C26—C25−176.53 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···O1i0.952.683.326 (2)126
Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formulaC17H20N2O
Mr268.35
Crystal system, space groupMonoclinic, P21/c
Temperature (K)200
a, b, c (Å)9.6990 (5), 16.7622 (10), 10.6011 (5)
β (°) 118.854 (4)
V (Å3)1509.52 (14)
Z4
Radiation typeMo Kα
µ (mm−1)0.07
Crystal size (mm)0.44 × 0.27 × 0.20
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		14247, 3723, 2926
Rint0.030
(sin θ/λ)max (Å−1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.141, 1.04
No. of reflections3723
No. of parameters183
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.20, −0.22

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···O1i0.952.683.326 (2)126
Symmetry code: (i) −x+1, −y+1, −z+1.
 

Acknowledgements

The authors thank Mr Matthew Mackay for helpful discussions.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
 First citationBruker (2010). APEX2 and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationEtter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256–262.  CrossRef CAS Web of Science IUCr Journals Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
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ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o827
doi:10.1107/S1600536811008294
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