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Acta Cryst. (2009). E65, o40    [ doi:10.1107/S1600536808040701 ]

1-(3-Chlorophenyl)-3-(1-p-tolylimidazolidin-2-ylidene)urea

W. Wysocki, D. Matosiuk, Z. Karczmarzyk, S. Fidecka and A. Fruzinski

Abstract top

In the crystal structure of the title compound, C17H17ClN4O, the existence of only one 2-imino-oxo of the five possible N-amino-imino/O-keto-hydroxy tautomers is observed and the dihedral angle between the aromatic rings is 29.78 (11)°. The molecular conformation is stabilized by intramolecular C-H...N, N-H...O and C-H...O hydrogen bonds, in each case generating a six-membered ring. In the crystal structure, the glide-plane-related molecules are linked into C(4) amide chains by intermolecular N-H...O hydrogen bonds, and an intermolecular C-H...O link also occurs.

Comment top

We report herein the results of the X-ray structure determination of the title compound, (I), as part of a structural study on a tautomeric equilibrium of the chain and fused derivatives of 2-aminoimidazoline with pharmacological activity (Matosiuk et al., 2001, 2005; Karczmarzyk et al., 2004; Wysocki et al., 2006). Investigated compound (I) exhibited central activity associated with agonistic action on opioid mu and delta (MOP and DOP) as well as serotonin (5-HT2) receptors. This activity was expressed by its strong antinociceptive, serotonergic and antidepressant action (Matosiuk et al., 2001). In the crystalline state, the compound (I) exists as the N3-amino/N6-imino/O8-keto/N9-amino tautomeric form with the amino and carbonyl groups involved in the strong N3—H31···O8 intramolecular and N9—H91···O8 intermolecular hydrogen bonds with π-bond cooperativity (Steiner, 2002) (Table 1 and 2). The geometry (bond lengths, angles and planarity) of the molecule of (I) is very similar to that observed in a previously reported close related structure of 1-(1-phenylimidazolidin-2-ylidene)-3-(4-chlorophenyl)urea (Matosiuk et al., 2001). The p-tolyl, 2-iminoimidazoline, urea and chlorophenyl groups are planar to within 0.047 (4), 0.084 (3), 0.006 (2) and 0.006 (2) Å, respectively, and the dihedral angles between mean planes of these groups are in the range of 6.86 (6)–29.88 (6)°. The carbonyl group is in cis conformation with the torsion angles C2—N6—C7—O8 and O8—C7—N9—C31 of 1.5 (3) and -7.8 (3)°, respectively. The nearly planar chain-extended conformation of the molecule as a whole is stabilized by the intramolecular C26—H261···N6, N3—H31···O8 and C32—H321···O8 hydrogen bonds (Table 2) leading to the formation of six-ring fused system. In the crystal structure, besides of the N9—H91···O8 intermolecular hydrogen bond linking the glide plane-related molecules into molecular chains along the [001] direction with graph-set motif C(4) (Bernstein et al., 1995), the π-electron systems of the imidazoline and phenyl rings belonging to inversion-related molecules overlap each other: the shortest intermolecular contact is C2···C22j=3.292 (3) Å and the angle between the overlapping planes is 16.83°, characteristic of π-stacking [symmetry code: (j) -x, -y, -z].

Related literature top

For general background, synthesis, biological activity and related structures, see: Matosiuk et al. (2001, 2005); Karczmarzyk et al. (2004); Wysocki et al. (2006). For hydrigen-bond motifs, see: Steiner (2002); Bernstein et al. (1995).

Experimental top

The title compound was synthesized from respective aniline via N-aryloethylenediamine, 1-aryl-2-aminoimidazoline-2 and final condensation with aromatic isocyanate according to the method of Matosiuk et al., (2001). Colourless prisms of (I) were grown by slow evaporation of an ethanol solution.

Refinement top

N-bound H atoms were located by difference Fourier synthesis and refined freely. The remaining H atoms were positioned geometrically and treated as riding on their C atoms, with C—H distances of 0.93 (aromatic), 0.97 (CH2) and 0.96 Å (CH3). All H atoms were assigned Uiso(H) values of 1.5Ueq(N,C).

Computing details top

Data collection: KM4B8 (Gałdecki et al., 1996); cell refinement: KM4B8 (Gałdecki et al., 1996); data reduction: DATAPROC (Gałdecki et al., 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with 50% probability displacement ellipsoids for non-H atoms.
[Figure 2] Fig. 2. The packing of (I), viewed down the a axis, showing molecules connected by N—H···O and C—H···O hydrogen bonds [symmetry code: (i) x, -y + 1/2, z - 1/2].
1-(3-Chlorophenyl)-3-(1-p-tolylimidazolidin-2-ylidene)urea top
Crystal data top
C17H17ClN4OF(000) = 688
Mr = 328.80Dx = 1.347 Mg m−3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 11.4506 (8) Åθ = 20.4–37.9°
b = 15.5097 (17) ŵ = 2.17 mm−1
c = 9.2811 (11) ÅT = 293 K
β = 100.506 (8)°Prism, colourless
V = 1620.7 (3) Å30.5 × 0.4 × 0.1 mm
Z = 4
Data collection top
Kuma KM-4 four-circle
diffractometer		Rint = 0.022
graphiteθmax = 80.3°, θmin = 3.9°
ω–2θ scansh = −14→1
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)		k = −19→1
Tmin = 0.398, Tmax = 0.805l = −11→11
4241 measured reflections2 standard reflections every 100 reflections
3485 independent reflections intensity decay: 1%
2703 reflections with I > 2σ(I)
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.055H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.165 w = 1/[σ2(Fo2) + (0.1001P)2 + 0.2753P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
3485 reflectionsΔρmax = 0.37 e Å−3
215 parametersΔρmin = −0.25 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008)
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0059 (8)
Crystal data top
C17H17ClN4OV = 1620.7 (3) Å3
Mr = 328.80Z = 4
Monoclinic, P21/cCu Kα radiation
a = 11.4506 (8) ŵ = 2.17 mm−1
b = 15.5097 (17) ÅT = 293 K
c = 9.2811 (11) Å0.5 × 0.4 × 0.1 mm
β = 100.506 (8)°
Data collection top
Kuma KM-4 four-circle
diffractometer		2703 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)		Rint = 0.022
Tmin = 0.398, Tmax = 0.805θmax = 80.3°
4241 measured reflections2 standard reflections every 100 reflections
3485 independent reflections intensity decay: 1%
Refinement top
R[F2 > 2σ(F2)] = 0.055H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.165Δρmax = 0.37 e Å−3
S = 1.05Δρmin = −0.25 e Å−3
3485 reflectionsAbsolute structure: ?
215 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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. Weighted least-squares planes through the starred atoms (Nardelli, Musatti, Domiano & Andreetti Ric.Sci.(1965),15(II—A),807). Equation of the plane: m1*X+m2*Y+m3*Z=d

Plane 1 m1 = 0.90393(0.00040) m2 = 0.30333(0.00097) m3 = -0.30149(0.00070) D = -1.33176(0.00722) Atom d s d/s (d/s)**2 C21 * -0.0098 0.0019 - 5.243 27.491 C22 * -0.0036 0.0021 - 1.701 2.893 C23 * 0.0143 0.0022 6.386 40.780 C24 * 0.0139 0.0024 5.729 32.824 C25 * 0.0142 0.0029 4.973 24.734 C26 * 0.0023 0.0026 0.875 0.766 C27 * -0.0475 0.0036 - 13.219 174.733 ============ Sum((d/s)**2) for starred atoms 304.221 Chi-squared at 95% for 4 degrees of freedom: 9.49 The group of atoms deviates significantly from planarity

Plane 2 m1 = 0.80521(0.00072) m2 = 0.56672(0.00100) m3 = -0.17457(0.00103) D = 1.23989(0.01043) Atom d s d/s (d/s)**2 N1 * -0.0082 0.0017 - 4.965 24.648 C2 * 0.0362 0.0018 20.251 410.085 N3 * -0.0538 0.0019 - 28.155 792.719 C4 * 0.0837 0.0027 31.025 962.555 C5 * -0.0338 0.0026 - 13.108 171.815 ============ Sum((d/s)**2) for starred atoms 2361.821 Chi-squared at 95% for 2 degrees of freedom: 5.99 The group of atoms deviates significantly from planarity

Plane 3 m1 = 0.71121(0.00067) m2 = 0.67408(0.00074) m3 = -0.19949(0.00094) D = 1.85835(0.00799) Atom d s d/s (d/s)**2 N6 * 0.0013 0.0015 0.821 0.673 C7 * -0.0058 0.0019 - 3.151 9.926 N9 * 0.0014 0.0017 0.843 0.710 O8 * 0.0015 0.0015 0.999 0.997 ============ Sum((d/s)**2) for starred atoms 12.306 Chi-squared at 95% for 1 degrees of freedom: 3.84 The group of atoms deviates significantly from planarity

Plane 4 m1 = 0.62657(0.00064) m2 = 0.73566(0.00060) m3 = -0.25731(0.00040) D = 1.62379(0.00373) Atom d s d/s (d/s)**2 C31 * 0.0038 0.0018 2.177 4.737 C32 * -0.0021 0.0021 - 0.989 0.978 C33 * 0.0061 0.0024 2.568 6.596 C34 * 0.0044 0.0025 1.711 2.926 C35 * 0.0004 0.0024 0.180 0.032 C36 * -0.0065 0.0020 - 3.250 10.562 Cl37 * -0.0008 0.0009 - 0.883 0.780 ============ Sum((d/s)**2) for starred atoms 26.612 Chi-squared at 95% for 4 degrees of freedom: 9.49 The group of atoms deviates significantly from planarity

Dihedral angles formed by LSQ-planes Plane - plane angle (s.u.) angle (s.u.) 1 2 17.75 (0.07) 162.25 (0.07) 1 3 24.84 (0.07) 155.16 (0.07) 1 4 29.88 (0.06) 150.12 (0.06) 2 3 8.31 (0.06) 171.69 (0.06) 2 4 14.91 (0.06) 165.09 (0.06) 3 4 6.86 (0.06) 173.14 (0.06)

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
N1−0.09936 (14)0.43729 (11)0.57376 (17)0.0563 (4)
C2−0.01993 (15)0.39274 (12)0.67403 (19)0.0492 (4)
N3−0.01904 (16)0.42651 (13)0.80768 (19)0.0627 (5)
H310.034 (3)0.408 (2)0.870 (3)0.094*
C4−0.0828 (2)0.50708 (18)0.8019 (2)0.0739 (6)
H41−0.02870.55540.82330.111*
H42−0.13760.50730.87020.111*
C5−0.1490 (2)0.50998 (17)0.6438 (2)0.0709 (6)
H51−0.23380.50290.6390.106*
H52−0.13480.56410.59740.106*
N60.04359 (13)0.32839 (10)0.63777 (16)0.0493 (4)
C70.12813 (16)0.29293 (12)0.74519 (18)0.0476 (4)
O80.15118 (13)0.31364 (10)0.87643 (14)0.0618 (4)
N90.18900 (14)0.22979 (11)0.68843 (16)0.0527 (4)
H910.170 (2)0.2200 (17)0.588 (3)0.079*
C21−0.14323 (16)0.41676 (13)0.4251 (2)0.0535 (4)
C22−0.20757 (18)0.47920 (14)0.3367 (2)0.0588 (5)
H221−0.21740.53370.37460.088*
C23−0.25711 (19)0.46083 (16)0.1925 (2)0.0647 (5)
H231−0.29920.50370.1350.097*
C24−0.2459 (2)0.38109 (17)0.1321 (2)0.0699 (6)
C25−0.1811 (3)0.31957 (18)0.2211 (3)0.0819 (8)
H251−0.17160.26520.18250.123*
C26−0.1300 (2)0.33600 (16)0.3655 (2)0.0717 (6)
H261−0.0870.29320.42230.108*
C27−0.3058 (3)0.3593 (2)−0.0224 (3)0.0987 (10)
H271−0.38460.3385−0.02160.148*
H272−0.2610.3157−0.06130.148*
H273−0.310.4101−0.08230.148*
C310.29140 (16)0.18486 (11)0.75469 (18)0.0475 (4)
C320.34463 (19)0.19435 (13)0.9002 (2)0.0597 (5)
H3210.31270.23180.96110.09*
C330.4462 (2)0.14726 (15)0.9541 (2)0.0665 (6)
C340.4955 (2)0.09095 (17)0.8697 (3)0.0713 (6)
H3410.56340.05980.90830.107*
C350.4410 (2)0.08155 (16)0.7248 (3)0.0674 (6)
H3510.47320.04360.6650.101*
C360.33986 (17)0.12737 (13)0.6673 (2)0.0536 (4)
H3610.30420.11970.56980.08*
Cl370.51115 (8)0.16036 (6)1.13661 (8)0.1143 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0552 (8)0.0643 (9)0.0447 (8)0.0130 (7)−0.0037 (6)−0.0031 (7)
C20.0462 (8)0.0592 (10)0.0393 (8)0.0018 (7)0.0004 (6)0.0012 (7)
N30.0623 (10)0.0803 (12)0.0424 (8)0.0166 (9)0.0014 (7)−0.0065 (8)
C40.0757 (14)0.0855 (16)0.0569 (12)0.0241 (12)0.0029 (10)−0.0130 (11)
C50.0685 (12)0.0811 (15)0.0590 (12)0.0232 (11)0.0005 (10)−0.0102 (11)
N60.0500 (8)0.0569 (8)0.0367 (7)0.0070 (6)−0.0037 (6)0.0010 (6)
C70.0512 (9)0.0543 (9)0.0337 (7)0.0017 (7)−0.0021 (6)0.0031 (7)
O80.0720 (9)0.0738 (9)0.0345 (6)0.0170 (7)−0.0037 (6)−0.0026 (6)
N90.0583 (8)0.0614 (9)0.0329 (7)0.0117 (7)−0.0063 (6)−0.0008 (6)
C210.0470 (9)0.0655 (11)0.0436 (9)0.0047 (8)−0.0029 (7)0.0019 (8)
C220.0542 (10)0.0605 (11)0.0569 (11)0.0009 (8)−0.0025 (8)0.0087 (9)
C230.0574 (11)0.0751 (13)0.0553 (11)0.0018 (10)−0.0065 (8)0.0169 (10)
C240.0666 (12)0.0888 (16)0.0472 (10)0.0055 (11)−0.0084 (9)0.0040 (10)
C250.0937 (17)0.0854 (16)0.0540 (12)0.0259 (14)−0.0203 (12)−0.0114 (11)
C260.0812 (14)0.0739 (14)0.0497 (11)0.0231 (11)−0.0155 (10)−0.0047 (9)
C270.112 (2)0.115 (2)0.0541 (13)0.0148 (18)−0.0255 (14)−0.0012 (14)
C310.0506 (9)0.0489 (9)0.0394 (8)0.0016 (7)−0.0011 (7)0.0032 (7)
C320.0669 (12)0.0619 (11)0.0431 (9)0.0141 (9)−0.0092 (8)−0.0031 (8)
C330.0681 (12)0.0695 (13)0.0521 (11)0.0138 (10)−0.0147 (9)−0.0001 (9)
C340.0628 (12)0.0794 (14)0.0648 (13)0.0215 (11)−0.0067 (10)0.0016 (11)
C350.0631 (12)0.0762 (14)0.0602 (12)0.0149 (10)0.0044 (9)−0.0041 (10)
C360.0555 (10)0.0597 (10)0.0429 (9)0.0028 (8)0.0024 (7)−0.0005 (8)
Cl370.1317 (7)0.1242 (7)0.0627 (4)0.0537 (5)−0.0466 (4)−0.0179 (4)
Geometric parameters (Å, °) top
N1—C21.365 (2)C23—C241.374 (4)
N1—C211.416 (2)C23—H2310.93
N1—C51.467 (3)C24—C251.386 (3)
C2—N61.314 (2)C24—C271.510 (3)
C2—N31.345 (2)C25—C261.385 (3)
N3—C41.443 (3)C25—H2510.93
N3—H310.81 (3)C26—H2610.93
C4—C51.524 (3)C27—H2710.96
C4—H410.97C27—H2720.96
C4—H420.97C27—H2730.96
C5—H510.97C31—C321.385 (2)
C5—H520.97C31—C361.388 (3)
N6—C71.372 (2)C32—C331.387 (3)
C7—O81.241 (2)C32—H3210.93
C7—N91.363 (2)C33—C341.362 (3)
N9—C311.406 (2)C33—Cl371.734 (2)
N9—H910.93 (3)C34—C351.383 (3)
C21—C261.388 (3)C34—H3410.93
C21—C221.390 (3)C35—C361.381 (3)
C22—C231.384 (3)C35—H3510.93
C22—H2210.93C36—H3610.93
C2—N1—C21128.66 (16)C24—C23—H231119.1
C2—N1—C5110.55 (16)C22—C23—H231119.1
C21—N1—C5120.49 (15)C23—C24—C25117.1 (2)
N6—C2—N3128.35 (17)C23—C24—C27121.9 (2)
N6—C2—N1122.75 (16)C25—C24—C27120.9 (2)
N3—C2—N1108.89 (17)C26—C25—C24122.4 (2)
C2—N3—C4112.58 (17)C26—C25—H251118.8
C2—N3—H31113 (2)C24—C25—H251118.8
C4—N3—H31130 (2)C25—C26—C21119.6 (2)
N3—C4—C5102.76 (17)C25—C26—H261120.2
N3—C4—H41111.2C21—C26—H261120.2
C5—C4—H41111.2C24—C27—H271109.5
N3—C4—H42111.2C24—C27—H272109.5
C5—C4—H42111.2H271—C27—H272109.5
H41—C4—H42109.1C24—C27—H273109.5
N1—C5—C4103.82 (17)H271—C27—H273109.5
N1—C5—H51111H272—C27—H273109.5
C4—C5—H51111C32—C31—C36119.13 (16)
N1—C5—H52111C32—C31—N9123.91 (17)
C4—C5—H52111C36—C31—N9116.96 (15)
H51—C5—H52109C31—C32—C33119.11 (19)
C2—N6—C7117.94 (15)C31—C32—H321120.4
O8—C7—N9122.24 (16)C33—C32—H321120.4
O8—C7—N6127.25 (17)C34—C33—C32122.6 (2)
N9—C7—N6110.50 (14)C34—C33—Cl37119.23 (16)
C7—N9—C31129.19 (14)C32—C33—Cl37118.18 (17)
C7—N9—H91117.4 (17)C33—C34—C35117.79 (19)
C31—N9—H91112.5 (17)C33—C34—H341121.1
C26—C21—C22118.55 (18)C35—C34—H341121.1
C26—C21—N1123.07 (17)C36—C35—C34121.3 (2)
C22—C21—N1118.30 (18)C36—C35—H351119.4
C23—C22—C21120.4 (2)C34—C35—H351119.4
C23—C22—H221119.8C35—C36—C31120.09 (17)
C21—C22—H221119.8C35—C36—H361120
C24—C23—C22121.85 (19)C31—C36—H361120
C21—N1—C2—N611.5 (3)N1—C21—C22—C23−176.89 (19)
C5—N1—C2—N6−175.0 (2)C21—C22—C23—C240.6 (3)
C21—N1—C2—N3−169.24 (19)C22—C23—C24—C25−0.9 (4)
C5—N1—C2—N34.3 (2)C22—C23—C24—C27176.4 (3)
N6—C2—N3—C4168.4 (2)C23—C24—C25—C260.6 (4)
N1—C2—N3—C4−10.8 (3)C27—C24—C25—C26−176.7 (3)
C2—N3—C4—C512.3 (3)C24—C25—C26—C210.0 (5)
C2—N1—C5—C43.2 (3)C22—C21—C26—C25−0.3 (4)
C21—N1—C5—C4177.4 (2)N1—C21—C26—C25176.5 (2)
N3—C4—C5—N1−8.8 (3)C7—N9—C31—C325.0 (3)
N3—C2—N6—C7−4.7 (3)C7—N9—C31—C36−175.62 (19)
N1—C2—N6—C7174.45 (17)C36—C31—C32—C331.1 (3)
C2—N6—C7—O81.5 (3)N9—C31—C32—C33−179.5 (2)
C2—N6—C7—N9−177.46 (17)C31—C32—C33—C34−0.8 (4)
O8—C7—N9—C31−7.8 (3)C31—C32—C33—Cl37179.97 (17)
N6—C7—N9—C31171.18 (18)C32—C33—C34—C350.3 (4)
C2—N1—C21—C2614.4 (3)Cl37—C33—C34—C35179.6 (2)
C5—N1—C21—C26−158.6 (2)C33—C34—C35—C36−0.2 (4)
C2—N1—C21—C22−168.8 (2)C34—C35—C36—C310.6 (4)
C5—N1—C21—C2218.2 (3)C32—C31—C36—C35−1.1 (3)
C26—C21—C22—C230.0 (3)N9—C31—C36—C35179.5 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H31···O80.81 (3)1.98 (3)2.611 (2)134 (3)
C26—H261···N60.932.332.919 (3)121
C32—H321···O80.932.262.864 (3)122
N9—H91···O8i0.93 (3)2.01 (3)2.927 (2)171 (2)
C36—H361···O8i0.932.493.266 (2)141
Symmetry codes: (i) x, −y+1/2, z−1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H31···O80.81 (3)1.98 (3)2.611 (2)134 (3)
C26—H261···N60.932.332.919 (3)121
C32—H321···O80.932.262.864 (3)122
N9—H91···O8i0.93 (3)2.01 (3)2.927 (2)171 (2)
C36—H361···O8i0.932.493.266 (2)141
Symmetry codes: (i) x, −y+1/2, z−1/2.
references
References top

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