1,2,3,4-Tetra­chloro-11,11-di­methoxy-1,4,5,6,9,10-hexa­hydro-endo-1,4-exo-6,9-di­methano­naphthalene

The title compound, C₁₄H₁₄Cl₄O₂, is the endo product of a Diels-Alder reaction between 1,2,3,4-tetra­chloro-5,5-di­methoxy­cyclo­penta-1,3-diene and bi­cyclo­[2.2.1]­hepta-2,5-diene. The mol­ecule possesses non-crystallographic C_s symmetry.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.035
• wR factor = 0.082
• Data-to-parameter ratio = 14.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

The title compound, (I), was produced as a key intermediate in the preparation of a hapten suitable for generating antibodies specific either for the organochlorine pesticide aldrin which has been shown to accumulate in fatty tissue or for dieldrin, the compound to which aldrin is metabolized by epoxidation in mammals. Both aldrin and dieldrin are known to persist in the environment and have been reported to possess carcinogenic properties by the Environmental Protection Agency in the USA (Stevenson et al., 1999).

The structure of the title compound was determined primarily to determine whether the product of the Diels–Alder reaction between 1,2,3,4-tetrachloro-5,5-dimethoxycyclopenta-1,3-diene and bicyclo[2.2.1]hepta-2,5-diene had an endo or an exo configuration. The molecule possesses non-crystallographic C_s symmetry, the mirror plane passing through C11 and C12, and bisecting the C2—C3, C5—C10 and C7—C8 bonds. The endo,exo-adduct is that required to match the stereochemistry of aldrin and dieldrin.

A number of related structures have been determined, for example, aldrin (1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-1,4:5,8- dimethanonaphthalene; DeLacy et al., 1972), isodrin (1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-endo-1,4-endo-5,8- dimethanonaphthalene; Kennard et al., 1979) and dechloroethoxyisodrin (endo,endo-3,5,6,11,11-pentachloro-4-ethoxytetracyclo[6.2.1.1^3,6.0^2,7]- dodeca-4,9-diene; Mackenzie et al., 1993).

S2. Experimental

The title compound was prepared by a Diels–Alder reaction between 1,2,3,4-tetrachloro-5,5-dimethoxycyclopenta-1,3-diene (2.0 ml, 3.00 g, 0.011 mol) and bicyclo[2.2.1]hepta-2,5-diene (3.5 ml, 3.00 g, 0.033 mol) following the method described by McCulloch et al. (1969). The two oils were mixed together and heated under reflux (358 K) overnight. The crude product was then purified by distillation first at atmospheric pressure to remove the unreacted bicyclo[2.2.1]hepta-2,5-diene and the under high vacuum with the required product distilling over at 409–413 K at 1 mm H g. The product solidified in the receiver and was purified by recrystallization from acetone/petroleum ether to afford 0.76 g of white needle-like crystals (19% yield), m.p. 389–391 K; δH (CDCl₃): 6.28 (2H, s, 7,8-CH), 3.59 (3H, s, 11-OCH₃), 3.55 (3H, s, 11-OCH₃), 2.82 (2H, br s, 6,9-CH), 2.55 (2H, s, 5,10-CH), 1.38 (2H, dd, J 10 and 18 Hz, 12-CH₂). Crystal suitable for diffraction studies were grown from acetone/petroleum ether.

S3. Refinement

The crystal was transferred into the nitrogen stream of an Oxford Cryosystems open-flow cryostat (Cosier & Glazer, 1986) operating at 150 (2) K. H atoms were located from difference Fourier syntheses and their geometries were idealized. Methyl H atoms were refined as part of a rigid group with U_iso(H) = 1.5U_eq(C); other H atoms were refined using a riding model and with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: STADI-4 (Stoe & Cie, 1995); cell refinement: STADI-4; data reduction: X-RED (Stoe & Cie, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1994); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2001).

Figures

Fig. 1. A general view of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

(I)

Crystal data

C14H14Cl4O2	Dx = 1.586 Mg m^−3
Mr = 356.05	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pbca	Cell parameters from 44 reflections
a = 13.259 (5) Å	θ = 13–15°
b = 14.383 (4) Å	µ = 0.79 mm^−1
c = 15.635 (4) Å	T = 150 K
V = 2981.7 (16) Å^3	Block, colourless
Z = 8	0.77 × 0.50 × 0.48 mm
F(000) = 1456

Data collection

Stoe Stadi-4 four-circle diffractometer	2298 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.00
Graphite monochromator	θmax = 25.0°, θmin = 2.6°
ω/θ scans	h = 0→15
Absorption correction: ψ scan (X-RED; Stoe & Cie, 1995)	k = 0→17
Tmin = 0.681, Tmax = 0.713	l = 0→18
2614 measured reflections	3 standard reflections every 60 min
2614 independent reflections	intensity decay: random variation +−2.0%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: see text
R[F^2 > 2σ(F^2)] = 0.035	H-atom parameters constrained
wR(F^2) = 0.082	w = 1/[σ^2(Fo^2) + (0.024P)^2 + 4.29P] where P = (Fo^2 + 2Fc^2)/3
S = 1.19	(Δ/σ)max = 0.001
2614 reflections	Δρmax = 0.36 e Å^−3
181 parameters	Δρmin = −0.34 e Å^−3
0 restraints

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.18999 (5)	0.01864 (5)	0.42727 (4)	0.02742 (18)
Cl2	0.39227 (5)	0.01685 (5)	0.55064 (5)	0.0326 (2)
Cl3	0.35599 (5)	0.16437 (5)	0.71855 (5)	0.03263 (19)
Cl4	0.13327 (5)	0.26233 (4)	0.70144 (4)	0.02667 (18)
O11A	0.19536 (14)	0.23992 (12)	0.51185 (11)	0.0227 (4)
O11B	0.04131 (13)	0.16331 (12)	0.51648 (11)	0.0213 (4)
C1	0.18486 (19)	0.06370 (17)	0.53275 (15)	0.0177 (5)
C2	0.28593 (18)	0.07777 (18)	0.57545 (16)	0.0199 (5)
C3	0.27154 (19)	0.13455 (18)	0.64081 (16)	0.0198 (5)
C4	0.16073 (19)	0.16024 (17)	0.64325 (15)	0.0179 (5)
C5	0.09464 (19)	0.07599 (17)	0.66788 (15)	0.0177 (5)
H5	0.0220	0.0948	0.6687	0.021*
C6	0.1189 (2)	0.01549 (17)	0.74850 (17)	0.0215 (6)
H6	0.1294	0.0496	0.8035	0.026*
C7	0.0345 (2)	−0.05631 (18)	0.74708 (18)	0.0250 (6)
H7	−0.0208	−0.0593	0.7856	0.030*
C8	0.0518 (2)	−0.11401 (19)	0.68256 (17)	0.0243 (6)
H8	0.0110	−0.1654	0.6665	0.029*
C9	0.14916 (19)	−0.08307 (17)	0.63860 (16)	0.0198 (5)
H9	0.1846	−0.1306	0.6028	0.024*
C10	0.11387 (18)	0.00742 (17)	0.59205 (16)	0.0176 (5)
H10	0.0489	−0.0049	0.5616	0.021*
C11	0.14117 (18)	0.16481 (17)	0.54391 (15)	0.0173 (5)
C11A	0.1948 (2)	0.2534 (2)	0.42122 (18)	0.0347 (7)
H11A	0.2354	0.3081	0.4068	0.052*
H11B	0.1253	0.2628	0.4016	0.052*
H11C	0.2232	0.1984	0.3931	0.052*
C11B	−0.0179 (2)	0.2456 (2)	0.5317 (2)	0.0334 (7)
H11D	−0.0864	0.2361	0.5098	0.050*
H11E	0.0131	0.2986	0.5024	0.050*
H11F	−0.0207	0.2580	0.5933	0.050*
C12	0.2057 (2)	−0.04778 (18)	0.71849 (16)	0.0211 (5)
H12A	0.2213	−0.0980	0.7597	0.025*
H12B	0.2677	−0.0127	0.7042	0.025*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0371 (4)	0.0302 (4)	0.0150 (3)	0.0038 (3)	0.0037 (3)	−0.0040 (3)
Cl2	0.0198 (3)	0.0402 (4)	0.0378 (4)	0.0101 (3)	0.0081 (3)	0.0042 (3)
Cl3	0.0288 (4)	0.0343 (4)	0.0348 (4)	−0.0052 (3)	−0.0157 (3)	−0.0003 (3)
Cl4	0.0372 (4)	0.0196 (3)	0.0232 (3)	0.0023 (3)	0.0008 (3)	−0.0062 (3)
O11A	0.0267 (10)	0.0224 (9)	0.0189 (9)	−0.0034 (8)	−0.0015 (8)	0.0043 (7)
O11B	0.0179 (9)	0.0223 (9)	0.0237 (9)	0.0033 (7)	−0.0040 (7)	−0.0004 (7)
C1	0.0187 (12)	0.0204 (13)	0.0139 (12)	0.0012 (10)	0.0016 (10)	−0.0017 (10)
C2	0.0142 (12)	0.0236 (13)	0.0219 (13)	0.0023 (10)	0.0029 (10)	0.0055 (11)
C3	0.0186 (13)	0.0226 (13)	0.0181 (12)	−0.0035 (11)	−0.0034 (10)	0.0040 (11)
C4	0.0229 (13)	0.0160 (12)	0.0147 (12)	0.0021 (10)	0.0001 (10)	−0.0030 (10)
C5	0.0161 (12)	0.0201 (13)	0.0168 (12)	0.0016 (10)	0.0023 (10)	−0.0001 (10)
C6	0.0276 (14)	0.0210 (13)	0.0159 (12)	0.0006 (11)	0.0018 (11)	−0.0002 (11)
C7	0.0272 (14)	0.0247 (14)	0.0230 (13)	−0.0012 (12)	0.0081 (12)	0.0060 (12)
C8	0.0254 (14)	0.0207 (13)	0.0269 (14)	−0.0060 (11)	−0.0004 (11)	0.0041 (11)
C9	0.0217 (13)	0.0177 (13)	0.0199 (13)	0.0023 (11)	0.0020 (11)	−0.0006 (10)
C10	0.0155 (12)	0.0200 (13)	0.0172 (12)	0.0001 (10)	−0.0002 (10)	−0.0009 (10)
C11	0.0176 (12)	0.0195 (13)	0.0146 (12)	0.0007 (10)	−0.0006 (10)	−0.0010 (10)
C11A	0.0458 (18)	0.0364 (16)	0.0218 (14)	−0.0121 (15)	−0.0002 (13)	0.0088 (12)
C11B	0.0284 (15)	0.0290 (15)	0.0429 (17)	0.0119 (13)	−0.0072 (13)	−0.0019 (13)
C12	0.0237 (14)	0.0203 (13)	0.0193 (12)	0.0022 (11)	−0.0019 (11)	0.0024 (10)

Geometric parameters (Å, º)

Cl1—C1	1.773 (2)	C7—C8	1.326 (4)
Cl2—C2	1.705 (3)	C8—C9	1.529 (4)
Cl3—C3	1.707 (3)	C9—C12	1.543 (4)
Cl4—C4	1.765 (2)	C9—C10	1.563 (3)
O11A—C11	1.391 (3)	C5—H5	1.0000
O11A—C11A	1.430 (3)	C6—H6	1.0000
O11B—C11	1.392 (3)	C7—H7	0.9500
O11B—C11B	1.440 (3)	C8—H8	0.9500
C1—C2	1.511 (4)	C9—H9	1.0000
C1—C10	1.549 (3)	C10—H10	1.0000
C1—C11	1.575 (3)	C11A—H11A	0.9800
C2—C3	1.322 (4)	C11A—H11B	0.9800
C3—C4	1.515 (4)	C11A—H11C	0.9800
C4—C5	1.544 (3)	C11B—H11D	0.9800
C4—C11	1.576 (3)	C11B—H11E	0.9800
C5—C10	1.563 (3)	C11B—H11F	0.9800
C5—C6	1.565 (3)	C12—H12A	0.9900
C6—C7	1.523 (4)	C12—H12B	0.9900
C6—C12	1.541 (4)
C11—O11A—C11A	117.3 (2)	O11A—C11—C4	107.61 (19)
C11—O11B—C11B	117.1 (2)	O11B—C11—C4	117.4 (2)
C2—C1—C10	110.1 (2)	C1—C11—C4	90.58 (18)
C2—C1—C11	98.83 (19)	C6—C12—C9	94.4 (2)
C10—C1—C11	101.11 (19)	C4—C5—H5	109.7
C2—C1—Cl1	115.21 (18)	C10—C5—H5	109.7
C10—C1—Cl1	112.89 (17)	C6—C5—H5	109.7
C11—C1—Cl1	117.04 (17)	C7—C6—H6	116.6
C3—C2—C1	107.2 (2)	C12—C6—H6	116.6
C3—C2—Cl2	127.8 (2)	C5—C6—H6	116.6
C1—C2—Cl2	124.34 (19)	C8—C7—H7	126.0
C2—C3—C4	108.1 (2)	C6—C7—H7	126.0
C2—C3—Cl3	127.6 (2)	C7—C8—H8	126.1
C4—C3—Cl3	123.82 (19)	C9—C8—H8	126.1
C3—C4—C5	111.4 (2)	C8—C9—H9	116.7
C3—C4—C11	98.33 (19)	C12—C9—H9	116.7
C5—C4—C11	100.67 (19)	C10—C9—H9	116.7
C3—C4—Cl4	114.57 (18)	C1—C10—H10	109.4
C5—C4—Cl4	114.03 (17)	C9—C10—H10	109.4
C11—C4—Cl4	116.06 (17)	C5—C10—H10	109.4
C4—C5—C10	102.32 (19)	O11A—C11A—H11A	109.5
C4—C5—C6	121.4 (2)	O11A—C11A—H11B	109.5
C10—C5—C6	103.10 (19)	H11A—C11A—H11B	109.5
C7—C6—C12	98.3 (2)	O11A—C11A—H11C	109.5
C7—C6—C5	102.4 (2)	H11A—C11A—H11C	109.5
C12—C6—C5	103.7 (2)	H11B—C11A—H11C	109.5
C8—C7—C6	108.0 (2)	O11B—C11B—H11D	109.5
C7—C8—C9	107.8 (2)	O11B—C11B—H11E	109.5
C8—C9—C12	98.2 (2)	H11D—C11B—H11E	109.5
C8—C9—C10	101.5 (2)	O11B—C11B—H11F	109.5
C12—C9—C10	104.4 (2)	H11D—C11B—H11F	109.5
C1—C10—C9	122.1 (2)	H11E—C11B—H11F	109.5
C1—C10—C5	102.90 (19)	C6—C12—H12A	112.8
C9—C10—C5	102.76 (19)	C9—C12—H12A	112.8
O11A—C11—O11B	113.1 (2)	C6—C12—H12B	112.8
O11A—C11—C1	119.2 (2)	C9—C12—H12B	112.8
O11B—C11—C1	107.54 (19)	H12A—C12—H12B	110.3
C10—C1—C2—C3	−68.4 (3)	C8—C9—C10—C1	−176.4 (2)
C11—C1—C2—C3	36.9 (2)	C12—C9—C10—C1	81.9 (3)
Cl1—C1—C2—C3	162.47 (18)	C8—C9—C10—C5	69.2 (2)
C10—C1—C2—Cl2	103.1 (2)	C12—C9—C10—C5	−32.4 (2)
C11—C1—C2—Cl2	−151.55 (19)	C4—C5—C10—C1	−2.2 (2)
Cl1—C1—C2—Cl2	−26.0 (3)	C6—C5—C10—C1	−129.0 (2)
C1—C2—C3—C4	−0.3 (3)	C4—C5—C10—C9	125.4 (2)
Cl2—C2—C3—C4	−171.43 (19)	C6—C5—C10—C9	−1.3 (2)
C1—C2—C3—Cl3	172.06 (19)	C11A—O11A—C11—O11B	−53.3 (3)
Cl2—C2—C3—Cl3	0.9 (4)	C11A—O11A—C11—C1	74.5 (3)
C2—C3—C4—C5	68.6 (3)	C11A—O11A—C11—C4	175.4 (2)
Cl3—C3—C4—C5	−104.1 (2)	C11B—O11B—C11—O11A	−54.5 (3)
C2—C3—C4—C11	−36.4 (2)	C11B—O11B—C11—C1	171.9 (2)
Cl3—C3—C4—C11	150.91 (19)	C11B—O11B—C11—C4	71.7 (3)
C2—C3—C4—Cl4	−160.11 (18)	C2—C1—C11—O11A	56.4 (3)
Cl3—C3—C4—Cl4	27.2 (3)	C10—C1—C11—O11A	169.1 (2)
C3—C4—C5—C10	−63.3 (2)	Cl1—C1—C11—O11A	−67.9 (3)
C11—C4—C5—C10	40.2 (2)	C2—C1—C11—O11B	−173.26 (19)
Cl4—C4—C5—C10	165.14 (16)	C10—C1—C11—O11B	−60.6 (2)
C3—C4—C5—C6	50.6 (3)	Cl1—C1—C11—O11B	62.5 (2)
C11—C4—C5—C6	154.0 (2)	C2—C1—C11—C4	−54.2 (2)
Cl4—C4—C5—C6	−81.0 (3)	C10—C1—C11—C4	58.4 (2)
C4—C5—C6—C7	179.3 (2)	Cl1—C1—C11—C4	−178.52 (17)
C10—C5—C6—C7	−67.3 (2)	C3—C4—C11—O11A	−67.3 (2)
C4—C5—C6—C12	−78.9 (3)	C5—C4—C11—O11A	178.96 (19)
C10—C5—C6—C12	34.6 (2)	Cl4—C4—C11—O11A	55.4 (2)
C12—C6—C7—C8	−34.6 (3)	C3—C4—C11—O11B	163.8 (2)
C5—C6—C7—C8	71.5 (3)	C5—C4—C11—O11B	50.1 (3)
C6—C7—C8—C9	0.3 (3)	Cl4—C4—C11—O11B	−73.5 (3)
C7—C8—C9—C12	34.0 (3)	C3—C4—C11—C1	53.7 (2)
C7—C8—C9—C10	−72.6 (3)	C5—C4—C11—C1	−60.1 (2)
C2—C1—C10—C9	−46.9 (3)	Cl4—C4—C11—C1	176.33 (17)
C11—C1—C10—C9	−150.7 (2)	C7—C6—C12—C9	52.3 (2)
Cl1—C1—C10—C9	83.4 (3)	C5—C6—C12—C9	−52.7 (2)
C2—C1—C10—C5	67.4 (2)	C8—C9—C12—C6	−52.0 (2)
C11—C1—C10—C5	−36.4 (2)	C10—C9—C12—C6	52.1 (2)
Cl1—C1—C10—C5	−162.28 (16)