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

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ISSN: 2414-3146

3,5-Di­chloro-3′,4′-di­meth­­oxy­biphen­yl

aThe University of Iowa, Department of Occupational and Environmental Health, University of Iowa Research Park, Iowa City, IA 52242, USA, and bDepartment of Chemistry, University of Kentucky, Lexington, KY 40506, USA
*Correspondence e-mail: hans-joachim-lehmler@uiowa.edu

Edited by J. Simpson, University of Otago, New Zealand (Received 12 April 2019; accepted 15 April 2019; online 25 April 2019)

The title compound, C14H12Cl2O2, is a dimethoxylated derivative of 3,4-di­chloro­biphenyl (PCB 14). The dihedral angle between the benzene rings is 42.49 (6)°. The meth­oxy groups on the non-chlorinated ring lie essentially in the plane of the benzene ring, with C—C—O—C torsion angles of 4.0 (2) and −2.07 (19)°. In the crystal, the compound displays ππ stacking inter­actions between inversion-related chlorinated benzene rings, with an inter­planar stacking distance of 3.3695 (17) Å.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Polychlorinated bi­phenyls (PCBs) are persistent organic pollutants that can be metabolized to mono- and di-hy­droxy­lated PCB metabolites (Grimm et al., 2015[Grimm, F. A., Hu, D., Kania-Korwel, I., Lehmler, H. J., Ludewig, G., Hornbuckle, K. C., Duffel, M. W., Bergman, A. & Robertson, L. W. (2015). Crit. Rev. Toxicol. 45, 245-272.]; Kania-Korwel & Lehmler, 2016[Kania-Korwel, I. & Lehmler, H. J. (2016). Environ. Sci. Pollut. Res. Int. 23, 2042-2057.]). The inter­action of PCB metabolites with biological macromolecules, such as proteins, depends on their three-dimensional structure. For example, non-ortho-substituted PCB congeners bind to the aryl hydro­carbon receptor (AhR) (Bandiera et al., 1982[Bandiera, S., Safe, S. & Okey, A. B. (1982). Chem. Biol. Interact. 39, 259-277.]), whereas PCB congeners with multiple ortho-chlorine substituents are potent sensitizers of ryanodine receptors (RyR) (Holland et al., 2017[Holland, E. B., Feng, W., Zheng, J., Dong, Y., Li, X., Lehmler, H.-J. & Pessah, I. N. (2017). Toxicol. Sci. 155, 170-181.]; Pessah et al., 2006[Pessah, I. N., Hansen, L. G., Albertson, T. E., Garner, C. E., Ta, T. A., Do, Z., Kim, K. H. & Wong, P. W. (2006). Chem. Res. Toxicol. 19, 92-101.]). The three-dimensional structure of PCB derivatives depends on their substitution pattern and the dihedral angle between the two benzene rings of the biphenyl moiety. However, only limited information about the structure of PCBs and their metabolites is currently available. Here we report the crystal structure of the title compound, 3,5-di­chloro-3′,4′-di­meth­oxy­biphenyl, a precursor for the synthesis of 3,5-di­chloro-3′,4′-di­hydroxy­biphenyl, a putative di­hydroxy­lated PCB metabolite of PCB 12.

The title compound (Fig. 1[link]) crystallizes in the monoclinic space group P21/c and shows ππ stacking inter­actions between inversion-related C1–C6 rings, with an inter­planar stacking distance of 3.3695 (17) Å. The dihedral angle between the least-squares mean planes of the two benzene rings is 42.49 (6)°. Similarly, the solid-state dihedral angles of other non-ortho-chlorine-substituted PCB derivatives range from 4.9 to 43.94° (e.g., see: Li et al., 2010[Li, X., Parkin, S., Duffel, M. W., Robertson, L. W. & Lehmler, H.-J. (2010). Acta Cryst. E66, o2306.]; Shaikh et al., 2008[Shaikh, N. S., Parkin, S., Luthe, G. & Lehmler, H.-J. (2008). Chemosphere, 70, 1694-1698.]). Larger dihedral angles are typically reported for PCB derivatives with one or more ortho-chlorine substituents (e.g., see: Lehmler et al., 2001[Lehmler, H.-J., Parkin, S. & Robertson, L. W. (2001). Acta Cryst. E57, o111-o112.]; Vyas et al., 2006[Vyas, S. M., Parkin, S. & Lehmler, H.-J. (2006). Acta Cryst. E62, o2905-o2906.]). Both meth­oxy groups are almost coplanar with the benzene ring, with torsion angles of 4.0 (2)° and −2.09 (19)° for the meth­oxy groups at C3′ and C4′, respectively. This orientation of the meth­oxy groups relative to the plane of the benzene ring is typical for meth­oxy­lated benzene derivatives that do not have substituents ortho to the respective meth­oxy group (Lehmler et al., 2013[Lehmler, H.-J., Wu, H. & Parkin, S. (2013). Acta Cryst. E69, o650.]).

[Figure 1]
Figure 1
View of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.

Synthesis and crystallization

The title compound was prepared via a Suzuki cross-coupling reaction of 3-bromo-1,2-di­meth­oxy­benzene with 3,5-di­chloro­phenyl­boronic acid in the presence of Pd(PPh3)4 and a 2M aqueous solution of Na2CO3 (Bauer et al., 1995[Bauer, U., Amaro, A. R. & Robertson, L. (1995). Chem. Res. Toxicol. 8, 92-95.]). Crystals suitable for structure analysis were obtained by recrystallization of the title compound from diethyl ether:hexa­nes (approximately 1:3, v/v) as described by Bauer et al. (1995[Bauer, U., Amaro, A. R. & Robertson, L. (1995). Chem. Res. Toxicol. 8, 92-95.]).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1[link]. Refinement progress was checked using PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and by an R-tensor (Parkin, 2000[Parkin, S. (2000). Acta Cryst. A56, 157-162.]).

Table 1
Experimental details

Crystal data
Chemical formula C14H12Cl2O2
Mr 283.14
Crystal system, space group Monoclinic, P21/c
Temperature (K) 90
a, b, c (Å) 10.8596 (10), 15.1262 (10), 7.9040 (3)
β (°) 103.749 (10)
V3) 1261.14 (16)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.50
Crystal size (mm) 0.35 × 0.35 × 0.30
 
Data collection
Diffractometer Nonius KappaCCD diffractometer
Absorption correction Multi-scan (SCALEPACK; Otwinowski & Minor, 2006[Otwinowski, Z. & Minor, W. (2006). International Tables for Crystallography, Vol. F, ch. 11.4, 226-235. Chester: International Union of Crystallography.])
Tmin, Tmax 0.843, 0.863
No. of measured, independent and observed [I > 2σ(I)] reflections 11657, 2899, 2521
Rint 0.036
(sin θ/λ)max−1) 0.649
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.072, 1.09
No. of reflections 2899
No. of parameters 166
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.29, −0.24
Computer programs: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]), SCALEPACK (Otwinowski & Minor, 2006[Otwinowski, Z. & Minor, W. (2006). International Tables for Crystallography, Vol. F, ch. 11.4, 226-235. Chester: International Union of Crystallography.]), DENZO-SMN (Otwinowski & Minor, 2006[Otwinowski, Z. & Minor, W. (2006). International Tables for Crystallography, Vol. F, ch. 11.4, 226-235. Chester: International Union of Crystallography.]), SHELXS (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2018 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), XP in SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELX (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and CIFFIX (Parkin, 2013[Parkin, S. (2013). CIFFIX, http://xray.uky.edu/people/parkin/programs/ciffix]).

Structural data


Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 2006); data reduction: DENZO-SMN (Otwinowski & Minor, 2006); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELX (Sheldrick, 2008) and CIFFIX (Parkin, 2013).

3,5-Dichloro-3',4'-dimethoxybiphenyl top
Crystal data top
C14H12Cl2O2F(000) = 584
Mr = 283.14Dx = 1.491 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 10.8596 (10) ÅCell parameters from 6723 reflections
b = 15.1262 (10) Åθ = 1.0–27.5°
c = 7.9040 (3) ŵ = 0.50 mm1
β = 103.749 (10)°T = 90 K
V = 1261.14 (16) Å3Block, colourless
Z = 40.35 × 0.35 × 0.30 mm
Data collection top
Nonius KappaCCD
diffractometer
2899 independent reflections
Radiation source: fine-focus sealed-tube2521 reflections with I > 2σ(I)
Detector resolution: 9.1 pixels mm-1Rint = 0.036
φ and ω scans at fixed χ = 55°θmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan
(Scalepack; Otwinowski & Minor, 2006)
h = 1413
Tmin = 0.843, Tmax = 0.863k = 1919
11657 measured reflectionsl = 1010
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.030H-atom parameters constrained
wR(F2) = 0.072 w = 1/[σ2(Fo2) + (0.0274P)2 + 0.5814P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max < 0.001
2899 reflectionsΔρmax = 0.29 e Å3
166 parametersΔρmin = 0.24 e Å3
0 restraintsExtinction correction: SHELXL2018 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0036 (10)
Special details top

Experimental. The crystal was mounted using polyisobutene oil on the tip of a fine glass fibre, which was fastened in a copper mounting pin with electrical solder. It was placed directly into the cold gas stream of a liquid-nitrogen-based cryostat.

Diffraction data were collected with the crystal at 90K, which is standard practice in this laboratory for the majority of flash-cooled crystals.

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 progress was checked using PLATON (Spek, 2009) and by an R-tensor (Parkin, 2000). The final model was further checked with the IUCr utility checkCIF.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.60753 (3)0.14404 (3)0.24758 (5)0.02195 (11)
Cl20.68140 (3)0.00465 (2)0.89050 (4)0.01849 (11)
C10.38939 (13)0.13567 (9)0.59009 (18)0.0143 (3)
C20.43570 (13)0.15454 (9)0.44322 (18)0.0158 (3)
H20.3847400.1859340.3477800.019*
C30.55644 (14)0.12705 (10)0.43819 (18)0.0161 (3)
C40.63554 (13)0.08233 (9)0.57460 (18)0.0162 (3)
H40.7186270.0647280.5698570.019*
C50.58725 (13)0.06454 (9)0.71870 (18)0.0147 (3)
C60.46684 (13)0.09022 (9)0.72952 (18)0.0153 (3)
H60.4372750.0770750.8305740.018*
C1'0.25668 (13)0.15968 (9)0.59000 (17)0.0144 (3)
C2'0.17925 (13)0.09856 (9)0.65066 (17)0.0141 (3)
H2'0.2139970.0442360.7006030.017*
C3'0.05248 (13)0.11749 (9)0.63765 (17)0.0138 (3)
C4'0.00084 (13)0.19851 (9)0.56645 (17)0.0142 (3)
C5'0.07794 (14)0.25948 (9)0.51099 (18)0.0155 (3)
H5'0.0442670.3149240.4658400.019*
C6'0.20519 (14)0.23956 (10)0.52135 (18)0.0166 (3)
H6'0.2570300.2812500.4808690.020*
O10.03319 (9)0.06153 (6)0.68480 (13)0.0172 (2)
C70.01422 (14)0.02040 (9)0.76311 (19)0.0174 (3)
H7A0.0575910.0521470.6859960.026*
H7B0.0563870.0562940.7821710.026*
H7C0.0740530.0090680.8749890.026*
O20.12548 (9)0.20904 (6)0.55654 (13)0.0171 (2)
C80.18099 (14)0.29114 (9)0.4881 (2)0.0177 (3)
H8A0.1402730.3396810.5629570.027*
H8B0.2718510.2904360.4842480.027*
H8C0.1688980.2995780.3701830.027*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0224 (2)0.0305 (2)0.01586 (18)0.00474 (15)0.01035 (14)0.00050 (15)
Cl20.01430 (18)0.0238 (2)0.01618 (18)0.00001 (13)0.00128 (13)0.00173 (14)
C10.0154 (7)0.0134 (7)0.0142 (6)0.0019 (5)0.0035 (5)0.0031 (5)
C20.0172 (7)0.0156 (7)0.0146 (7)0.0014 (5)0.0036 (5)0.0002 (5)
C30.0185 (7)0.0180 (7)0.0136 (7)0.0060 (6)0.0072 (6)0.0027 (5)
C40.0128 (7)0.0177 (7)0.0188 (7)0.0034 (5)0.0051 (5)0.0042 (6)
C50.0153 (7)0.0144 (7)0.0131 (6)0.0020 (5)0.0006 (5)0.0013 (5)
C60.0160 (7)0.0169 (7)0.0141 (6)0.0038 (5)0.0059 (5)0.0009 (6)
C1'0.0154 (7)0.0170 (7)0.0109 (6)0.0005 (5)0.0033 (5)0.0023 (5)
C2'0.0166 (7)0.0136 (6)0.0113 (6)0.0008 (5)0.0019 (5)0.0002 (5)
C3'0.0155 (7)0.0150 (7)0.0111 (6)0.0027 (5)0.0034 (5)0.0007 (5)
C4'0.0140 (7)0.0169 (7)0.0114 (6)0.0006 (5)0.0025 (5)0.0026 (5)
C5'0.0203 (7)0.0129 (7)0.0133 (6)0.0014 (5)0.0040 (6)0.0006 (5)
C6'0.0193 (7)0.0172 (7)0.0150 (7)0.0022 (6)0.0071 (6)0.0012 (6)
O10.0141 (5)0.0150 (5)0.0228 (5)0.0000 (4)0.0049 (4)0.0057 (4)
C70.0175 (7)0.0158 (7)0.0183 (7)0.0001 (5)0.0029 (6)0.0040 (6)
O20.0137 (5)0.0164 (5)0.0213 (5)0.0033 (4)0.0042 (4)0.0033 (4)
C80.0176 (7)0.0144 (7)0.0212 (7)0.0047 (5)0.0049 (6)0.0007 (6)
Geometric parameters (Å, º) top
Cl1—C31.7439 (14)C3'—O11.3732 (16)
Cl2—C51.7464 (14)C3'—C4'1.4082 (19)
C1—C61.398 (2)C4'—O21.3646 (16)
C1—C21.3998 (19)C4'—C5'1.385 (2)
C1—C1'1.4861 (19)C5'—C6'1.398 (2)
C2—C31.385 (2)C5'—H5'0.9500
C2—H20.9500C6'—H6'0.9500
C3—C41.385 (2)O1—C71.4256 (17)
C4—C51.389 (2)C7—H7A0.9800
C4—H40.9500C7—H7B0.9800
C5—C61.386 (2)C7—H7C0.9800
C6—H60.9500O2—C81.4293 (16)
C1'—C6'1.387 (2)C8—H8A0.9800
C1'—C2'1.408 (2)C8—H8B0.9800
C2'—C3'1.3858 (19)C8—H8C0.9800
C2'—H2'0.9500
C6—C1—C2119.12 (13)O1—C3'—C4'114.44 (12)
C6—C1—C1'121.49 (12)C2'—C3'—C4'120.25 (13)
C2—C1—C1'119.29 (12)O2—C4'—C5'125.39 (13)
C3—C2—C1119.46 (13)O2—C4'—C3'115.09 (12)
C3—C2—H2120.3C5'—C4'—C3'119.52 (13)
C1—C2—H2120.3C4'—C5'—C6'120.11 (13)
C4—C3—C2122.72 (13)C4'—C5'—H5'119.9
C4—C3—Cl1118.61 (11)C6'—C5'—H5'119.9
C2—C3—Cl1118.57 (11)C1'—C6'—C5'120.78 (13)
C3—C4—C5116.61 (13)C1'—C6'—H6'119.6
C3—C4—H4121.7C5'—C6'—H6'119.6
C5—C4—H4121.7C3'—O1—C7117.10 (11)
C6—C5—C4122.82 (13)O1—C7—H7A109.5
C6—C5—Cl2118.94 (11)O1—C7—H7B109.5
C4—C5—Cl2118.22 (11)H7A—C7—H7B109.5
C5—C6—C1119.27 (13)O1—C7—H7C109.5
C5—C6—H6120.4H7A—C7—H7C109.5
C1—C6—H6120.4H7B—C7—H7C109.5
C6'—C1'—C2'119.18 (13)C4'—O2—C8116.80 (11)
C6'—C1'—C1120.93 (13)O2—C8—H8A109.5
C2'—C1'—C1119.79 (12)O2—C8—H8B109.5
C3'—C2'—C1'120.13 (13)H8A—C8—H8B109.5
C3'—C2'—H2'119.9O2—C8—H8C109.5
C1'—C2'—H2'119.9H8A—C8—H8C109.5
O1—C3'—C2'125.28 (13)H8B—C8—H8C109.5
C6—C1—C2—C30.7 (2)C1—C1'—C2'—C3'174.65 (12)
C1'—C1—C2—C3175.75 (13)C1'—C2'—C3'—O1176.85 (12)
C1—C2—C3—C41.1 (2)C1'—C2'—C3'—C4'1.1 (2)
C1—C2—C3—Cl1175.29 (11)O1—C3'—C4'—O20.44 (17)
C2—C3—C4—C51.0 (2)C2'—C3'—C4'—O2178.57 (12)
Cl1—C3—C4—C5175.35 (11)O1—C3'—C4'—C5'178.72 (12)
C3—C4—C5—C60.6 (2)C2'—C3'—C4'—C5'0.6 (2)
C3—C4—C5—Cl2177.65 (10)O2—C4'—C5'—C6'177.32 (13)
C4—C5—C6—C10.3 (2)C3'—C4'—C5'—C6'1.8 (2)
Cl2—C5—C6—C1177.94 (10)C2'—C1'—C6'—C5'0.4 (2)
C2—C1—C6—C50.3 (2)C1—C1'—C6'—C5'175.76 (13)
C1'—C1—C6—C5176.03 (13)C4'—C5'—C6'—C1'1.3 (2)
C6—C1—C1'—C6'142.42 (14)C2'—C3'—O1—C74.0 (2)
C2—C1—C1'—C6'41.23 (19)C4'—C3'—O1—C7177.97 (12)
C6—C1—C1'—C2'41.44 (19)C5'—C4'—O2—C82.07 (19)
C2—C1—C1'—C2'134.91 (14)C3'—C4'—O2—C8178.82 (12)
C6'—C1'—C2'—C3'1.6 (2)
 

Acknowledgements

The Nonius KappaCCD diffractometer was funded by the University of Kentucky.

Funding information

Funding for this research was provided by: National Institute of Environmental Health Sciences (grant No. P42 ES013661; grant No. P30 ES005605; grant No. R21 ES027169).

References

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