organic compounds
1,1,1-Trichloro-2,2-bis(4-ethoxyphenyl)ethane
aScience and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia
*Correspondence e-mail: g.smith@qut.edu.au
In the title compound, C18H19Cl3O2, which is the 4-ethoxyphenyl analogue of the insecticidally active 4-methoxyphenyl compound methoxychlor, the dihedral angle between the two benzene rings is 60.38 (13)°. An intramolecular aromatic C—H⋯Cl interaction is present.
Related literature
For background to DDT-type insecticides, see: Läuger et al. (1944). For unit-cell data for the title compound, see: Schneider & Fankuchen (1946). For the structures of analogous p-alkoxy-substituted DDT compounds, see: Smith et al. (1976); Smith (2012).
Experimental
Crystal data
|
Refinement
|
|
Data collection: CrysAlis PRO (Agilent, 2012); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON.
Supporting information
10.1107/S1600536812043826/lh5546sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812043826/lh5546Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812043826/lh5546Isup3.cml
The title compound was obtained as an analytical reference standard from the US Public Health Service. Colourless crystal prisms suitable for X-ray analysis were obtained by room temperature evaporation of a solution of the title compound in ethanol.
Hydrogen atoms were included in the
at calculated positions [C—H = 0.93–0.98 Å, with Uiso(H) = 1.2Ueq(C)(aromatic, methylene and methine) or 1.5Ueq(C)(methyl), using a riding-model approximation.Data collection: CrysAlis PRO (Agilent, 2012); cell
CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).C18H19Cl3O2 | F(000) = 776 |
Mr = 373.68 | Dx = 1.394 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 3070 reflections |
a = 23.4405 (7) Å | θ = 3.1–28.8° |
b = 9.8835 (2) Å | µ = 0.52 mm−1 |
c = 7.7924 (2) Å | T = 200 K |
β = 99.536 (3)° | Prism, colourless |
V = 1780.35 (8) Å3 | 0.30 × 0.15 × 0.08 mm |
Z = 4 |
Oxford Diffraction Gemini-S CCD-detector diffractometer | 3109 independent reflections |
Radiation source: Enhance (Mo) X-ray source | 2282 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.106 |
Detector resolution: 16.077 pixels mm-1 | θmax = 25.0°, θmin = 3.4° |
ω scans | h = −27→23 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012) | k = −11→11 |
Tmin = 0.960, Tmax = 0.980 | l = −9→9 |
10942 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.046 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.092 | H-atom parameters constrained |
S = 0.91 | w = 1/[σ2(Fo2) + (0.013P)2] where P = (Fo2 + 2Fc2)/3 |
3109 reflections | (Δ/σ)max < 0.001 |
210 parameters | Δρmax = 0.38 e Å−3 |
0 restraints | Δρmin = −0.25 e Å−3 |
C18H19Cl3O2 | V = 1780.35 (8) Å3 |
Mr = 373.68 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 23.4405 (7) Å | µ = 0.52 mm−1 |
b = 9.8835 (2) Å | T = 200 K |
c = 7.7924 (2) Å | 0.30 × 0.15 × 0.08 mm |
β = 99.536 (3)° |
Oxford Diffraction Gemini-S CCD-detector diffractometer | 3109 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012) | 2282 reflections with I > 2σ(I) |
Tmin = 0.960, Tmax = 0.980 | Rint = 0.106 |
10942 measured reflections |
R[F2 > 2σ(F2)] = 0.046 | 0 restraints |
wR(F2) = 0.092 | H-atom parameters constrained |
S = 0.91 | Δρmax = 0.38 e Å−3 |
3109 reflections | Δρmin = −0.25 e Å−3 |
210 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.33099 (3) | −0.05016 (8) | 0.40168 (9) | 0.0385 (3) | |
Cl2 | 0.23442 (3) | −0.19217 (7) | 0.50376 (9) | 0.0374 (3) | |
Cl3 | 0.21520 (3) | 0.01715 (8) | 0.24488 (9) | 0.0412 (3) | |
O4A | 0.02901 (9) | 0.0931 (2) | 0.7508 (3) | 0.0442 (8) | |
O4B | 0.44289 (8) | 0.0498 (2) | 1.1563 (2) | 0.0406 (7) | |
C1 | 0.25902 (12) | −0.0312 (3) | 0.4447 (3) | 0.0274 (9) | |
C1A | 0.19612 (11) | 0.0869 (3) | 0.6338 (3) | 0.0228 (9) | |
C1B | 0.30558 (11) | 0.0680 (3) | 0.7397 (3) | 0.0247 (9) | |
C2 | 0.25640 (11) | 0.0785 (3) | 0.5851 (3) | 0.0240 (9) | |
C2A | 0.17938 (12) | 0.0081 (3) | 0.7642 (3) | 0.0293 (10) | |
C2B | 0.31987 (12) | −0.0486 (3) | 0.8366 (3) | 0.0293 (9) | |
C3A | 0.12369 (13) | 0.0129 (3) | 0.7994 (4) | 0.0325 (10) | |
C3B | 0.36559 (12) | −0.0512 (3) | 0.9749 (4) | 0.0322 (10) | |
C4A | 0.08312 (12) | 0.0979 (3) | 0.7062 (4) | 0.0304 (10) | |
C4B | 0.39827 (12) | 0.0635 (3) | 1.0180 (3) | 0.0301 (10) | |
C5A | 0.09942 (12) | 0.1816 (3) | 0.5803 (3) | 0.0316 (10) | |
C5B | 0.38476 (12) | 0.1820 (3) | 0.9249 (3) | 0.0314 (10) | |
C6A | 0.15553 (12) | 0.1748 (3) | 0.5458 (3) | 0.0291 (9) | |
C6B | 0.33864 (12) | 0.1830 (3) | 0.7873 (3) | 0.0273 (9) | |
C11A | −0.01660 (13) | 0.1672 (3) | 0.6474 (4) | 0.0485 (11) | |
C11B | 0.48754 (13) | 0.1495 (3) | 1.1746 (4) | 0.0425 (11) | |
C21A | −0.07174 (14) | 0.1329 (4) | 0.7104 (5) | 0.0641 (16) | |
C21B | 0.53406 (13) | 0.1062 (3) | 1.3219 (4) | 0.0509 (14) | |
H2 | 0.26230 | 0.16490 | 0.52880 | 0.0290* | |
H2A | 0.20620 | −0.04910 | 0.82900 | 0.0350* | |
H2B | 0.29830 | −0.12680 | 0.80820 | 0.0350* | |
H3A | 0.11330 | −0.04150 | 0.88660 | 0.0390* | |
H3B | 0.37420 | −0.13040 | 1.03840 | 0.0390* | |
H5A | 0.07300 | 0.24180 | 0.51950 | 0.0380* | |
H5B | 0.40630 | 0.26010 | 0.95420 | 0.0380* | |
H6A | 0.16620 | 0.23110 | 0.46090 | 0.0350* | |
H6B | 0.32970 | 0.26270 | 0.72540 | 0.0330* | |
H11A | −0.01930 | 0.14280 | 0.52580 | 0.0580* | |
H11B | 0.47210 | 0.23700 | 1.20010 | 0.0510* | |
H12A | −0.00910 | 0.26360 | 0.65890 | 0.0580* | |
H12B | 0.50340 | 0.15690 | 1.06760 | 0.0510* | |
H21A | −0.10340 | 0.17870 | 0.63990 | 0.0960* | |
H21B | 0.56480 | 0.17140 | 1.33640 | 0.0760* | |
H22A | −0.06920 | 0.16110 | 0.82930 | 0.0960* | |
H22B | 0.54890 | 0.01940 | 1.29560 | 0.0760* | |
H23A | −0.07800 | 0.03700 | 0.70230 | 0.0960* | |
H23B | 0.51810 | 0.10010 | 1.42730 | 0.0760* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0348 (5) | 0.0443 (5) | 0.0374 (5) | 0.0061 (4) | 0.0093 (3) | −0.0034 (4) |
Cl2 | 0.0452 (5) | 0.0235 (4) | 0.0428 (5) | −0.0032 (3) | 0.0053 (4) | −0.0059 (3) |
Cl3 | 0.0453 (5) | 0.0481 (5) | 0.0263 (4) | 0.0079 (4) | −0.0054 (3) | −0.0015 (4) |
O4A | 0.0280 (13) | 0.0556 (15) | 0.0488 (14) | 0.0015 (11) | 0.0054 (10) | −0.0016 (11) |
O4B | 0.0327 (12) | 0.0469 (14) | 0.0373 (12) | −0.0064 (10) | −0.0081 (10) | 0.0016 (10) |
C1 | 0.0303 (17) | 0.0255 (16) | 0.0252 (15) | 0.0056 (13) | 0.0014 (13) | 0.0001 (13) |
C1A | 0.0249 (16) | 0.0193 (14) | 0.0230 (15) | 0.0016 (12) | 0.0005 (12) | −0.0031 (12) |
C1B | 0.0250 (16) | 0.0248 (15) | 0.0244 (15) | 0.0002 (13) | 0.0044 (12) | 0.0024 (13) |
C2 | 0.0288 (16) | 0.0162 (14) | 0.0254 (15) | 0.0014 (12) | −0.0003 (12) | 0.0003 (12) |
C2A | 0.0333 (18) | 0.0210 (15) | 0.0316 (17) | 0.0031 (13) | −0.0001 (14) | 0.0034 (13) |
C2B | 0.0276 (17) | 0.0269 (15) | 0.0314 (17) | −0.0041 (13) | −0.0007 (13) | 0.0021 (13) |
C3A | 0.0357 (18) | 0.0270 (16) | 0.0350 (18) | −0.0015 (14) | 0.0062 (14) | 0.0031 (14) |
C3B | 0.0337 (18) | 0.0307 (17) | 0.0315 (17) | 0.0014 (14) | 0.0030 (14) | 0.0064 (14) |
C4A | 0.0262 (17) | 0.0338 (17) | 0.0303 (17) | −0.0023 (14) | 0.0025 (14) | −0.0093 (14) |
C4B | 0.0289 (17) | 0.0385 (18) | 0.0219 (16) | 0.0016 (14) | 0.0014 (13) | −0.0041 (14) |
C5A | 0.0319 (18) | 0.0286 (17) | 0.0312 (17) | 0.0052 (14) | −0.0036 (14) | 0.0021 (14) |
C5B | 0.0306 (17) | 0.0301 (17) | 0.0328 (17) | −0.0063 (14) | 0.0036 (14) | −0.0070 (14) |
C6A | 0.0347 (18) | 0.0250 (15) | 0.0262 (16) | −0.0008 (13) | 0.0007 (13) | 0.0023 (13) |
C6B | 0.0302 (17) | 0.0251 (16) | 0.0268 (16) | 0.0010 (13) | 0.0051 (13) | 0.0018 (13) |
C11A | 0.0314 (19) | 0.050 (2) | 0.061 (2) | 0.0063 (17) | −0.0013 (17) | −0.0054 (18) |
C11B | 0.0329 (19) | 0.051 (2) | 0.0425 (19) | −0.0057 (16) | 0.0028 (15) | −0.0063 (16) |
C21A | 0.029 (2) | 0.065 (3) | 0.097 (3) | −0.0024 (19) | 0.007 (2) | −0.013 (2) |
C21B | 0.033 (2) | 0.066 (3) | 0.048 (2) | −0.0009 (17) | −0.0103 (16) | −0.0111 (18) |
Cl1—C1 | 1.784 (3) | C11A—C21A | 1.496 (5) |
Cl2—C1 | 1.779 (3) | C11B—C21B | 1.508 (4) |
Cl3—C1 | 1.783 (3) | C2—H2 | 0.9800 |
O4A—C4A | 1.370 (4) | C2A—H2A | 0.9300 |
O4A—C11A | 1.429 (4) | C2B—H2B | 0.9300 |
O4B—C4B | 1.379 (3) | C3A—H3A | 0.9300 |
O4B—C11B | 1.427 (4) | C3B—H3B | 0.9300 |
C1—C2 | 1.549 (4) | C5A—H5A | 0.9300 |
C1A—C2 | 1.525 (4) | C5B—H5B | 0.9300 |
C1A—C2A | 1.388 (4) | C6A—H6A | 0.9300 |
C1A—C6A | 1.384 (4) | C6B—H6B | 0.9300 |
C1B—C2 | 1.527 (3) | C11A—H11A | 0.9700 |
C1B—C2B | 1.388 (4) | C11A—H12A | 0.9700 |
C1B—C6B | 1.391 (4) | C11B—H11B | 0.9700 |
C2A—C3A | 1.379 (4) | C11B—H12B | 0.9700 |
C2B—C3B | 1.389 (4) | C21A—H21A | 0.9600 |
C3A—C4A | 1.382 (4) | C21A—H22A | 0.9600 |
C3B—C4B | 1.378 (4) | C21A—H23A | 0.9600 |
C4A—C5A | 1.385 (4) | C21B—H21B | 0.9600 |
C4B—C5B | 1.386 (4) | C21B—H22B | 0.9600 |
C5A—C6A | 1.387 (4) | C21B—H23B | 0.9600 |
C5B—C6B | 1.391 (4) | ||
C4A—O4A—C11A | 118.5 (2) | C3A—C2A—H2A | 119.00 |
C4B—O4B—C11B | 117.3 (2) | C1B—C2B—H2B | 119.00 |
Cl1—C1—Cl2 | 108.18 (16) | C3B—C2B—H2B | 119.00 |
Cl1—C1—Cl3 | 106.86 (13) | C2A—C3A—H3A | 120.00 |
Cl1—C1—C2 | 110.84 (19) | C4A—C3A—H3A | 120.00 |
Cl2—C1—Cl3 | 107.53 (15) | C2B—C3B—H3B | 120.00 |
Cl2—C1—C2 | 113.01 (18) | C4B—C3B—H3B | 120.00 |
Cl3—C1—C2 | 110.17 (19) | C4A—C5A—H5A | 120.00 |
C2—C1A—C2A | 122.5 (2) | C6A—C5A—H5A | 120.00 |
C2—C1A—C6A | 120.0 (2) | C4B—C5B—H5B | 120.00 |
C2A—C1A—C6A | 117.4 (2) | C6B—C5B—H5B | 120.00 |
C2—C1B—C2B | 124.6 (3) | C1A—C6A—H6A | 119.00 |
C2—C1B—C6B | 118.0 (2) | C5A—C6A—H6A | 119.00 |
C2B—C1B—C6B | 117.4 (2) | C1B—C6B—H6B | 119.00 |
C1—C2—C1A | 111.2 (2) | C5B—C6B—H6B | 119.00 |
C1—C2—C1B | 113.4 (2) | O4A—C11A—H11A | 110.00 |
C1A—C2—C1B | 114.7 (2) | O4A—C11A—H12A | 110.00 |
C1A—C2A—C3A | 121.2 (3) | C21A—C11A—H11A | 110.00 |
C1B—C2B—C3B | 121.6 (3) | C21A—C11A—H12A | 110.00 |
C2A—C3A—C4A | 120.6 (3) | H11A—C11A—H12A | 108.00 |
C2B—C3B—C4B | 120.0 (3) | O4B—C11B—H11B | 110.00 |
O4A—C4A—C3A | 115.5 (3) | O4B—C11B—H12B | 110.00 |
O4A—C4A—C5A | 125.2 (3) | C21B—C11B—H11B | 110.00 |
C3A—C4A—C5A | 119.3 (3) | C21B—C11B—H12B | 110.00 |
O4B—C4B—C3B | 115.4 (2) | H11B—C11B—H12B | 109.00 |
O4B—C4B—C5B | 124.8 (3) | C11A—C21A—H21A | 109.00 |
C3B—C4B—C5B | 119.9 (2) | C11A—C21A—H22A | 109.00 |
C4A—C5A—C6A | 119.4 (3) | C11A—C21A—H23A | 109.00 |
C4B—C5B—C6B | 119.4 (3) | H21A—C21A—H22A | 109.00 |
C1A—C6A—C5A | 122.1 (2) | H21A—C21A—H23A | 109.00 |
C1B—C6B—C5B | 121.8 (3) | H22A—C21A—H23A | 110.00 |
O4A—C11A—C21A | 107.8 (3) | C11B—C21B—H21B | 109.00 |
O4B—C11B—C21B | 107.8 (2) | C11B—C21B—H22B | 109.00 |
C1—C2—H2 | 106.00 | C11B—C21B—H23B | 110.00 |
C1A—C2—H2 | 106.00 | H21B—C21B—H22B | 109.00 |
C1B—C2—H2 | 106.00 | H21B—C21B—H23B | 109.00 |
C1A—C2A—H2A | 119.00 | H22B—C21B—H23B | 109.00 |
C11A—O4A—C4A—C3A | −173.3 (3) | C2B—C1B—C2—C1 | −52.8 (3) |
C11A—O4A—C4A—C5A | 8.0 (4) | C2B—C1B—C2—C1A | 76.3 (3) |
C4A—O4A—C11A—C21A | 173.7 (3) | C6B—C1B—C2—C1 | 127.1 (3) |
C11B—O4B—C4B—C3B | 162.2 (2) | C6B—C1B—C2—C1A | −103.8 (3) |
C11B—O4B—C4B—C5B | −18.4 (4) | C2—C1B—C2B—C3B | 179.4 (3) |
C4B—O4B—C11B—C21B | −174.3 (2) | C6B—C1B—C2B—C3B | −0.5 (4) |
Cl1—C1—C2—C1A | −175.16 (18) | C2—C1B—C6B—C5B | −179.1 (2) |
Cl1—C1—C2—C1B | −44.3 (3) | C2B—C1B—C6B—C5B | 0.8 (4) |
Cl2—C1—C2—C1A | −53.5 (3) | C1A—C2A—C3A—C4A | −0.7 (4) |
Cl2—C1—C2—C1B | 77.3 (3) | C1B—C2B—C3B—C4B | −0.5 (4) |
Cl3—C1—C2—C1A | 66.8 (2) | C2A—C3A—C4A—O4A | 179.2 (3) |
Cl3—C1—C2—C1B | −162.36 (19) | C2A—C3A—C4A—C5A | −2.0 (4) |
C2A—C1A—C2—C1 | 88.5 (3) | C2B—C3B—C4B—O4B | −179.5 (2) |
C2A—C1A—C2—C1B | −41.7 (4) | C2B—C3B—C4B—C5B | 1.1 (4) |
C6A—C1A—C2—C1 | −91.0 (3) | O4A—C4A—C5A—C6A | −179.0 (3) |
C6A—C1A—C2—C1B | 138.9 (3) | C3A—C4A—C5A—C6A | 2.4 (4) |
C2—C1A—C2A—C3A | −176.7 (3) | O4B—C4B—C5B—C6B | 179.9 (2) |
C6A—C1A—C2A—C3A | 2.8 (4) | C3B—C4B—C5B—C6B | −0.8 (4) |
C2—C1A—C6A—C5A | 177.1 (2) | C4A—C5A—C6A—C1A | −0.2 (4) |
C2A—C1A—C6A—C5A | −2.4 (4) | C4B—C5B—C6B—C1B | −0.2 (4) |
Experimental details
Crystal data | |
Chemical formula | C18H19Cl3O2 |
Mr | 373.68 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 200 |
a, b, c (Å) | 23.4405 (7), 9.8835 (2), 7.7924 (2) |
β (°) | 99.536 (3) |
V (Å3) | 1780.35 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.52 |
Crystal size (mm) | 0.30 × 0.15 × 0.08 |
Data collection | |
Diffractometer | Oxford Diffraction Gemini-S CCD-detector diffractometer |
Absorption correction | Multi-scan (CrysAlis PRO; Agilent, 2012) |
Tmin, Tmax | 0.960, 0.980 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10942, 3109, 2282 |
Rint | 0.106 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.046, 0.092, 0.91 |
No. of reflections | 3109 |
No. of parameters | 210 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.38, −0.25 |
Computer programs: CrysAlis PRO (Agilent, 2012), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999), PLATON (Spek, 2009).
Acknowledgements
The author acknowledges financial support from the Australian Research Council and the Science and Engineering Faculty and the University Library, Queensland University of Technology.
References
Agilent (2012). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England. Google Scholar
Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343–350. CrossRef Web of Science IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Läuger, P., Martin, H. & Müller, P. H. (1944). Helv. Chim. Acta, 27, 892–928. Google Scholar
Schneider, M. & Fankuchen, I. (1946). J. Am. Chem. Soc. 68, 2669–2670. CSD CrossRef CAS PubMed Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Smith, G. (2012). Acta Cryst. E68, o2544. CSD CrossRef IUCr Journals Google Scholar
Smith, G., Kennard, C. H. L. & White, A. H. (1976). Aust. J. Chem. 29, 743–747. CSD CrossRef CAS Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound, C18H19Cl302 is the 4-ethoxyphenyl analogue of the insecticides DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane] and methoxychlor (the 4-methoxyphenyl analogue), and has similar insecticidal activity (Läuger et al., 1944), but was not used as a commercial product. The crystal structures of methoxychlor (Smith et al., 1976) and the p-butoxy analogue (Smith, 2012) are known and the unit cell data for the title compound has been reported (Schneider & Fankuchen, 1946). The structure of the title compound is reported herein.
The molecular structure of the title compound is shown in Fig. 1. The unit cell and space group are consistent with those previously reported. The dihedral angle between the two benzene ring mean planes is 60.38 (13)°. The value of this angle is 77.7° (no s.u. available) in the structure of methoxychlor (Smith et al., 1976). The conformations of the two ethoxy side chains relative to their benzene rings (A and B) are similar [comparative torsion angles C3—C4—O4—C11, -173.3 (3) and 162.2 (2), respectively]. The B ring conformation is stabilized by an intramolecular aromatic C2B—H···Cl2 interaction (Table 1). No significant intermolecular interactions are present (Fig. 2).