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ISSN: 2056-9890

1,3-Bis(4-chloro­phen­yl)-4,5-di­eth­oxy­imidazolidine

aSchool of Chemistry and Chemical Engineering, Xuzhou Normal University, Xuzhou, Jiangsu 221116, People's Republic of China
*Correspondence e-mail: wuhui72@yahoo.com.cn

(Received 22 September 2008; accepted 26 September 2008; online 22 October 2008)

In the mol­ecule of the title compound, C19H22Cl2N2O2, the two benzene rings are oriented at a dihedral angle of 3.70 (3)°. The five-membered ring adopts an envelope conformation.

Related literature

For general background, see: Bunnage & Owen (2008[Bunnage, M. E. & Owen, D. R. (2008). Curr. Opin. Drug Discov. Dev. 11, 480-486.]); Weinreb (2007[Weinreb, S. M. (2007). Nat. Prod. Rep. 24, 931-948.]); Jin (2006[Jin, Z. (2006). Nat. Prod. Rep. 23, 464-498.]); Farnia et al. (1997[Farnia, S. M. F., Kakanejadifard, A. & Soudbar, D. (1997). Tetrahedron, 53, 2557-2564.]); Reed & Schleyer (1988[Reed, A. E. & Schleyer, D. V. R. (1988). Inorg. Chem. 27, 3969-3987.]). For bond-length data, 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
  • C19H22Cl2N2O2

  • Mr = 381.29

  • Monoclinic, P 21 /c

  • a = 10.928 (2) Å

  • b = 11.123 (2) Å

  • c = 16.006 (3) Å

  • β = 94.480 (15)°

  • V = 1939.6 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.35 mm−1

  • T = 296 (2) K

  • 0.50 × 0.42 × 0.22 mm

Data collection
  • Siemens P4 diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.843, Tmax = 0.926

  • 4160 measured reflections

  • 3609 independent reflections

  • 1867 reflections with I > 2σ(I)

  • Rint = 0.010

  • 3 standard reflections every 97 reflections intensity decay: 1.1%

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.072

  • S = 0.94

  • 3609 reflections

  • 227 parameters

  • H-atom parameters constrained

  • Δρmax = 0.12 e Å−3

  • Δρmin = −0.13 e Å−3

Data collection: XSCANS (Siemens, 1996[Siemens (1996). XSCANS. Siemens AXS Inc., Madison, Wisconsin, USA.]); cell refinement: XSCANS; data reduction: XSCANS; 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

Imidazoles are commonly utilized substructures within the pharmaceutical industry, as these heterocycles impart unique physical and biological properties to compounds of interest (Bunnage & Owen, 2008; Weinreb, 2007; Jin, 2006). Furthermore, molecules containing anomeric effect in N—C—N system influences many structural and electronic properties (Farnia et al., 1997; Reed & Schleyer, 1988). We report herein the synthesis and crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Rings A (C1-C6) and C (C10-C15) are, of course, planar and the dihedral angle between them is 3.70 (3)°. So, they are also nearly coplanar. Ring B (N1/N2/C7-C9) is not planar, and adopts envelope conformation with C8 atom displaced by 0.336 (3) Å from the plane of the other ring atoms.

Related literature top

For general background, see: Bunnage & Owen (2008); Weinreb (2007); Jin (2006); Farnia et al. (1997); Reed & Schleyer (1988). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound was simply prepared by the reaction of 4-chloro- benzaldehyde (2.0 mmol) with glyoxal(1.0 mmol) and formaldehyde (1.0 mmol) in ethanol (3.0 ml) at 273–278 K without catalyst for 40 h (yield; 81%). Single crystals suitable for X-ray analysis were obtained from an ethanol solution by slow evaporation.

Refinement top

H atoms were positioned geometrically, with C-H = 0.93, 0.98, 0.97 and 0.96 Å for aromatic, methine, methylene and methyl H, respectively, and constrained to ride on their parent atoms with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for all other H atoms.

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS (Siemens, 1996); data reduction: XSCANS (Siemens, 1996); 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. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
1,3-Bis(4-chlorophenyl)-4,5-diethoxyimidazolidine top
Crystal data top
C19H22Cl2N2O2F(000) = 800
Mr = 381.29Dx = 1.306 Mg m3
Monoclinic, P21/cMelting point = 445–446 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 10.928 (2) ÅCell parameters from 28 reflections
b = 11.123 (2) Åθ = 4.9–14.4°
c = 16.006 (3) ŵ = 0.35 mm1
β = 94.480 (15)°T = 296 K
V = 1939.6 (6) Å3Block, colorless
Z = 40.50 × 0.42 × 0.22 mm
Data collection top
Siemens P4
diffractometer
1867 reflections with I > 2σ(I)
Radiation source: normal-focus sealed tubeRint = 0.010
Graphite monochromatorθmax = 25.5°, θmin = 1.9°
ω scansh = 013
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 013
Tmin = 0.843, Tmax = 0.926l = 1919
4160 measured reflections3 standard reflections every 97 reflections
3609 independent reflections intensity decay: 1.1%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.072 w = 1/[σ2(Fo2) + (0.0226P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.94(Δ/σ)max = 0.001
3609 reflectionsΔρmax = 0.12 e Å3
227 parametersΔρmin = 0.13 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0056 (4)
Crystal data top
C19H22Cl2N2O2V = 1939.6 (6) Å3
Mr = 381.29Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.928 (2) ŵ = 0.35 mm1
b = 11.123 (2) ÅT = 296 K
c = 16.006 (3) Å0.50 × 0.42 × 0.22 mm
β = 94.480 (15)°
Data collection top
Siemens P4
diffractometer
1867 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
Rint = 0.010
Tmin = 0.843, Tmax = 0.9263 standard reflections every 97 reflections
4160 measured reflections intensity decay: 1.1%
3609 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.072H-atom parameters constrained
S = 0.94Δρmax = 0.12 e Å3
3609 reflectionsΔρmin = 0.13 e Å3
227 parameters
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.

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
Cl10.87517 (6)0.07126 (6)0.61089 (5)0.0967 (3)
Cl20.24717 (6)0.95415 (6)0.65343 (4)0.0981 (3)
O10.92261 (12)0.55731 (13)0.57515 (9)0.0596 (4)
O20.66798 (11)0.63533 (12)0.42946 (8)0.0586 (4)
N10.73769 (14)0.43816 (15)0.56395 (10)0.0544 (5)
N20.63188 (15)0.61147 (15)0.57001 (10)0.0547 (5)
C10.69410 (19)0.23950 (19)0.61290 (13)0.0576 (6)
H10.62100.26720.63200.069*
C20.7256 (2)0.1204 (2)0.62321 (13)0.0628 (6)
H20.67400.06810.64930.075*
C30.8326 (2)0.07892 (19)0.59514 (14)0.0601 (6)
C40.9094 (2)0.1553 (2)0.55715 (14)0.0669 (7)
H40.98200.12640.53800.080*
C50.8794 (2)0.2745 (2)0.54722 (13)0.0605 (6)
H50.93250.32630.52220.073*
C60.76964 (18)0.31880 (19)0.57444 (12)0.0481 (5)
C70.81176 (18)0.52749 (18)0.52714 (12)0.0520 (6)
H70.83270.49790.47240.062*
C80.72362 (17)0.63322 (18)0.51288 (12)0.0510 (5)
H80.76600.70930.52620.061*
C90.62711 (17)0.48661 (18)0.59411 (12)0.0517 (6)
H9A0.62720.47820.65440.062*
H9B0.55480.44740.56770.062*
C100.54049 (18)0.6921 (2)0.58676 (12)0.0482 (5)
C110.44177 (18)0.6556 (2)0.63022 (13)0.0587 (6)
H110.43540.57550.64580.070*
C120.3535 (2)0.7359 (2)0.65051 (14)0.0666 (7)
H120.28840.70960.67980.080*
C130.3603 (2)0.8540 (2)0.62809 (13)0.0613 (6)
C140.4559 (2)0.8919 (2)0.58461 (13)0.0651 (7)
H140.46100.97230.56920.078*
C150.54485 (19)0.8117 (2)0.56344 (13)0.0615 (6)
H150.60870.83850.53310.074*
C160.9094 (2)0.5868 (2)0.66041 (14)0.0808 (8)
H16A0.88700.51570.69080.097*
H16B0.84500.64620.66390.097*
C171.0262 (2)0.6350 (3)0.69752 (16)0.1104 (10)
H17A1.01830.65490.75520.166*
H17B1.04730.70580.66760.166*
H17C1.08940.57570.69410.166*
C180.7407 (2)0.6940 (2)0.37180 (15)0.0825 (8)
H18A0.81590.64930.36650.099*
H18B0.76240.77410.39190.099*
C190.6704 (2)0.7017 (3)0.29006 (15)0.1278 (12)
H19A0.71870.74170.25090.192*
H19B0.59620.74610.29570.192*
H19C0.65040.62210.27010.192*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0971 (5)0.0588 (4)0.1362 (6)0.0063 (4)0.0216 (5)0.0038 (4)
Cl20.0926 (5)0.0975 (6)0.1076 (6)0.0270 (4)0.0303 (4)0.0125 (4)
O10.0454 (9)0.0792 (11)0.0551 (10)0.0086 (8)0.0086 (7)0.0004 (9)
O20.0550 (9)0.0737 (10)0.0472 (9)0.0135 (8)0.0046 (7)0.0102 (8)
N10.0432 (10)0.0544 (12)0.0678 (12)0.0047 (10)0.0177 (9)0.0051 (10)
N20.0517 (11)0.0586 (12)0.0557 (11)0.0029 (10)0.0168 (9)0.0101 (10)
C10.0485 (13)0.0586 (15)0.0666 (16)0.0042 (12)0.0103 (12)0.0005 (13)
C20.0601 (15)0.0582 (16)0.0709 (16)0.0117 (13)0.0111 (13)0.0019 (13)
C30.0608 (15)0.0520 (15)0.0669 (16)0.0025 (13)0.0020 (13)0.0105 (13)
C40.0563 (15)0.0714 (18)0.0742 (17)0.0052 (14)0.0118 (13)0.0077 (15)
C50.0559 (15)0.0652 (17)0.0620 (16)0.0039 (13)0.0150 (12)0.0014 (13)
C60.0417 (12)0.0543 (15)0.0484 (13)0.0077 (12)0.0037 (11)0.0028 (11)
C70.0491 (13)0.0641 (15)0.0434 (13)0.0069 (12)0.0065 (11)0.0005 (12)
C80.0480 (13)0.0579 (14)0.0474 (14)0.0078 (12)0.0064 (11)0.0014 (12)
C90.0435 (13)0.0579 (15)0.0541 (14)0.0041 (11)0.0057 (11)0.0031 (12)
C100.0454 (13)0.0590 (15)0.0399 (13)0.0031 (12)0.0024 (11)0.0001 (11)
C110.0515 (14)0.0584 (15)0.0675 (15)0.0062 (13)0.0126 (12)0.0010 (13)
C120.0521 (15)0.0777 (18)0.0721 (17)0.0063 (14)0.0176 (13)0.0044 (15)
C130.0596 (15)0.0689 (17)0.0558 (15)0.0058 (14)0.0077 (12)0.0100 (13)
C140.0762 (17)0.0588 (16)0.0605 (15)0.0058 (14)0.0066 (14)0.0058 (13)
C150.0601 (15)0.0659 (17)0.0605 (15)0.0007 (13)0.0167 (12)0.0082 (13)
C160.0719 (17)0.117 (2)0.0537 (16)0.0122 (16)0.0074 (14)0.0114 (15)
C170.086 (2)0.150 (3)0.090 (2)0.005 (2)0.0247 (17)0.016 (2)
C180.0868 (18)0.0938 (19)0.0683 (18)0.0140 (16)0.0153 (16)0.0235 (15)
C190.131 (3)0.195 (3)0.0564 (18)0.041 (2)0.0022 (18)0.041 (2)
Geometric parameters (Å, º) top
Cl1—C31.747 (2)C9—H9A0.9700
Cl2—C131.736 (2)C9—H9B0.9700
O1—C161.422 (2)C10—C151.384 (3)
O1—C71.422 (2)C10—C111.389 (2)
O2—C181.423 (2)C11—C121.372 (3)
O2—C81.424 (2)C11—H110.9300
N1—C61.380 (2)C12—C131.365 (3)
N1—C71.437 (2)C12—H120.9300
N1—C91.440 (2)C13—C141.366 (3)
N2—C101.384 (2)C14—C151.381 (3)
N2—C81.429 (2)C14—H140.9300
N2—C91.443 (2)C15—H150.9300
C1—C21.376 (3)C16—C171.466 (3)
C1—C61.385 (2)C16—H16A0.9700
C1—H10.9300C16—H16B0.9700
C2—C31.366 (3)C17—H17A0.9600
C2—H20.9300C17—H17B0.9600
C3—C41.369 (3)C17—H17C0.9600
C4—C51.372 (3)C18—C191.467 (3)
C4—H40.9300C18—H18A0.9700
C5—C61.397 (3)C18—H18B0.9700
C5—H50.9300C19—H19A0.9600
C7—C81.526 (3)C19—H19B0.9600
C7—H70.9800C19—H19C0.9600
C8—H80.9800
C16—O1—C7115.22 (15)H9A—C9—H9B109.1
C18—O2—C8113.37 (16)N2—C10—C15122.01 (19)
C6—N1—C7124.76 (17)N2—C10—C11120.6 (2)
C6—N1—C9122.01 (16)C15—C10—C11117.4 (2)
C7—N1—C9113.14 (16)C12—C11—C10121.1 (2)
C10—N2—C8124.56 (17)C12—C11—H11119.4
C10—N2—C9121.99 (17)C10—C11—H11119.4
C8—N2—C9112.07 (16)C13—C12—C11120.7 (2)
C2—C1—C6121.0 (2)C13—C12—H12119.7
C2—C1—H1119.5C11—C12—H12119.7
C6—C1—H1119.5C12—C13—C14119.4 (2)
C3—C2—C1119.9 (2)C12—C13—Cl2120.12 (19)
C3—C2—H2120.1C14—C13—Cl2120.5 (2)
C1—C2—H2120.1C13—C14—C15120.4 (2)
C2—C3—C4120.4 (2)C13—C14—H14119.8
C2—C3—Cl1120.04 (18)C15—C14—H14119.8
C4—C3—Cl1119.48 (18)C14—C15—C10121.0 (2)
C3—C4—C5120.1 (2)C14—C15—H15119.5
C3—C4—H4119.9C10—C15—H15119.5
C5—C4—H4119.9O1—C16—C17108.81 (19)
C4—C5—C6120.5 (2)O1—C16—H16A109.9
C4—C5—H5119.8C17—C16—H16A109.9
C6—C5—H5119.8O1—C16—H16B109.9
N1—C6—C1120.87 (19)C17—C16—H16B109.9
N1—C6—C5121.08 (19)H16A—C16—H16B108.3
C1—C6—C5118.0 (2)C16—C17—H17A109.5
O1—C7—N1115.03 (16)C16—C17—H17B109.5
O1—C7—C8113.71 (17)H17A—C17—H17B109.5
N1—C7—C8103.01 (15)C16—C17—H17C109.5
O1—C7—H7108.3H17A—C17—H17C109.5
N1—C7—H7108.3H17B—C17—H17C109.5
C8—C7—H7108.3O2—C18—C19109.0 (2)
O2—C8—N2109.47 (16)O2—C18—H18A109.9
O2—C8—C7111.79 (16)C19—C18—H18A109.9
N2—C8—C7103.88 (16)O2—C18—H18B109.9
O2—C8—H8110.5C19—C18—H18B109.9
N2—C8—H8110.5H18A—C18—H18B108.3
C7—C8—H8110.5C18—C19—H19A109.5
N1—C9—N2102.80 (16)C18—C19—H19B109.5
N1—C9—H9A111.2H19A—C19—H19B109.5
N2—C9—H9A111.2C18—C19—H19C109.5
N1—C9—H9B111.2H19A—C19—H19C109.5
N2—C9—H9B111.2H19B—C19—H19C109.5
C6—C1—C2—C30.1 (3)C9—N2—C8—C721.7 (2)
C1—C2—C3—C40.4 (3)O1—C7—C8—O2138.53 (16)
C1—C2—C3—Cl1178.08 (16)N1—C7—C8—O296.31 (17)
C2—C3—C4—C50.2 (3)O1—C7—C8—N2103.52 (18)
Cl1—C3—C4—C5177.52 (17)N1—C7—C8—N221.63 (19)
C3—C4—C5—C61.0 (3)C6—N1—C9—N2179.82 (17)
C7—N1—C6—C1178.06 (18)C7—N1—C9—N23.1 (2)
C9—N1—C6—C11.7 (3)C10—N2—C9—N1179.41 (16)
C7—N1—C6—C51.4 (3)C8—N2—C9—N112.3 (2)
C9—N1—C6—C5177.81 (18)C8—N2—C10—C1514.3 (3)
C2—C1—C6—N1179.80 (19)C9—N2—C10—C15179.81 (19)
C2—C1—C6—C50.7 (3)C8—N2—C10—C11167.52 (18)
C4—C5—C6—N1179.23 (19)C9—N2—C10—C112.0 (3)
C4—C5—C6—C11.3 (3)N2—C10—C11—C12177.02 (19)
C16—O1—C7—N150.9 (2)C15—C10—C11—C121.2 (3)
C16—O1—C7—C867.6 (2)C10—C11—C12—C130.3 (3)
C6—N1—C7—O168.0 (2)C11—C12—C13—C140.4 (3)
C9—N1—C7—O1108.68 (19)C11—C12—C13—Cl2179.42 (17)
C6—N1—C7—C8167.75 (18)C12—C13—C14—C150.0 (3)
C9—N1—C7—C815.6 (2)Cl2—C13—C14—C15179.05 (16)
C18—O2—C8—N2160.47 (17)C13—C14—C15—C101.0 (3)
C18—O2—C8—C785.0 (2)N2—C10—C15—C14176.62 (19)
C10—N2—C8—O268.9 (2)C11—C10—C15—C141.6 (3)
C9—N2—C8—O297.87 (19)C7—O1—C16—C17170.4 (2)
C10—N2—C8—C7171.58 (17)C8—O2—C18—C19174.5 (2)

Experimental details

Crystal data
Chemical formulaC19H22Cl2N2O2
Mr381.29
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)10.928 (2), 11.123 (2), 16.006 (3)
β (°) 94.480 (15)
V3)1939.6 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.35
Crystal size (mm)0.50 × 0.42 × 0.22
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.843, 0.926
No. of measured, independent and
observed [I > 2σ(I)] reflections
4160, 3609, 1867
Rint0.010
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.072, 0.94
No. of reflections3609
No. of parameters227
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.12, 0.13

Computer programs: XSCANS (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

We are grateful to the National Science Foundation of China (grant No. 20772103), the Natural Science Foundation in Jiangsu Province (grant No. BK 2007028) and the Surpassing Project in Jiangsu Province (grant No. QL 200607) for financial support.

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