organic compounds
(1R,2R,5R,6S,9R,10S,13S,14S,18R)-1,6,7,8,9,14,15,16,17,17,18-Undecachloropentacyclo[12.2.1.16,9.02,13.05,10]octadeca-7,15-diene
aWellington Laboratories, Research Division, Guelph, Ontario, Canada N1G 3M5, bDepartment of Chemistry, University of Guelph, Ontario, Canada N1G 2W1, and cDepartment of Chemistry, University of Toronto, Ontario, Canada M5S 3H6
*Correspondence e-mail: alough@chem.utoronto.ca
The title compound, C18H13Cl11, is an undecachlorinated commercial flame retardant. The contains two independent half-molecules. The complete molecules are generated by crystallographic inversion symmetry, causing the terminal H atoms and one of the Cl atoms to be disordered equally over two sites in each molecule. The central eight-membered rings are in chair-type conformations. In the there is a single weak intermolecular C—H⋯Cl hydrogen bond.
Experimental
Crystal data
|
Refinement
|
Data collection: COLLECT (Nonius, 2002); cell DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO–SMN; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S160053680801622X/pk2101sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053680801622X/pk2101Isup2.hkl
The synthesis of the title compound was carried out at Wellington Laboratories using proprietary methods. The compound was isolated and purified using chromatographic techniques. For single-crystal x-ray crystallography, colourless crystals were grown from a solution in toluene.
All hydrogen atoms were placed in calculated positions with C—H distances of 0.99 and 1.00 Å and they were included in the
in a riding-model approximation with Uiso = 1.2Ueq(C).Data collection: COLLECT (Nonius, 2002); cell
DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO–SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C18H13Cl11 | F(000) = 1232 |
Mr = 619.23 | Dx = 1.755 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 15654 reflections |
a = 13.3129 (5) Å | θ = 2.8–27.5° |
b = 12.1263 (6) Å | µ = 1.31 mm−1 |
c = 14.7229 (7) Å | T = 150 K |
β = 99.505 (3)° | Block, colourless |
V = 2344.18 (18) Å3 | 0.26 × 0.20 × 0.15 mm |
Z = 4 |
Bruker–Nonius KappaCCD diffractometer | 5338 independent reflections |
Radiation source: fine-focus sealed tube | 3481 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.052 |
Detector resolution: 9 pixels mm-1 | θmax = 27.5°, θmin = 2.8° |
ϕ scans and ω scans with κ offsets | h = −17→17 |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | k = −14→15 |
Tmin = 0.715, Tmax = 0.825 | l = −16→19 |
15654 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.050 | H-atom parameters constrained |
wR(F2) = 0.118 | w = 1/[σ2(Fo2) + (0.0314P)2 + 4.5718P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max < 0.001 |
5338 reflections | Δρmax = 0.53 e Å−3 |
272 parameters | Δρmin = −0.68 e Å−3 |
0 restraints | Extinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0011 (3) |
C18H13Cl11 | V = 2344.18 (18) Å3 |
Mr = 619.23 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 13.3129 (5) Å | µ = 1.31 mm−1 |
b = 12.1263 (6) Å | T = 150 K |
c = 14.7229 (7) Å | 0.26 × 0.20 × 0.15 mm |
β = 99.505 (3)° |
Bruker–Nonius KappaCCD diffractometer | 5338 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | 3481 reflections with I > 2σ(I) |
Tmin = 0.715, Tmax = 0.825 | Rint = 0.052 |
15654 measured reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.118 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.53 e Å−3 |
5338 reflections | Δρmin = −0.68 e Å−3 |
272 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Cl1A | 0.12630 (8) | 0.59357 (8) | 0.23239 (6) | 0.0351 (3) | |
Cl2A | −0.04105 (8) | 0.77914 (9) | 0.28215 (7) | 0.0390 (3) | |
Cl3A | 0.03958 (8) | 0.87394 (8) | 0.49922 (7) | 0.0371 (3) | |
Cl4A | 0.25958 (7) | 0.75232 (9) | 0.58340 (7) | 0.0375 (3) | |
Cl5A | 0.28655 (8) | 0.77926 (10) | 0.35627 (7) | 0.0449 (3) | |
Cl6A | 0.32477 (14) | 0.57426 (16) | 0.42481 (15) | 0.0351 (5) | 0.50 |
C1A | 0.0896 (3) | 0.5390 (3) | 0.4083 (2) | 0.0235 (8) | |
H1A | 0.1293 | 0.4710 | 0.3993 | 0.028* | |
C2A | 0.1294 (3) | 0.5849 (3) | 0.5085 (2) | 0.0229 (8) | |
H2A | 0.1854 | 0.5355 | 0.5384 | 0.027* | |
C3A | 0.0525 (3) | 0.5978 (3) | 0.5746 (2) | 0.0246 (8) | |
H3A1 | −0.0099 | 0.6331 | 0.5412 | 0.030* | |
H3A2 | 0.0817 | 0.6477 | 0.6254 | 0.030* | |
C4A | −0.0227 (3) | 0.5119 (3) | 0.3837 (2) | 0.0268 (8) | |
H4A1 | −0.0412 | 0.5080 | 0.3158 | 0.032* | |
H4A2 | −0.0626 | 0.5724 | 0.4054 | 0.032* | |
C5A | 0.1236 (3) | 0.6328 (3) | 0.3464 (2) | 0.0255 (8) | |
C6A | 0.0612 (3) | 0.7346 (3) | 0.3593 (3) | 0.0263 (8) | |
C7A | 0.0923 (3) | 0.7720 (3) | 0.4438 (3) | 0.0243 (8) | |
C8A | 0.1776 (3) | 0.6973 (3) | 0.4878 (2) | 0.0245 (8) | |
C9A | 0.2268 (3) | 0.6680 (3) | 0.4039 (3) | 0.0289 (9) | |
H9C | 0.2739 | 0.6037 | 0.4170 | 0.035* | 0.50 |
Cl1B | 0.50434 (8) | 0.70192 (12) | 0.26767 (8) | 0.0573 (4) | |
Cl2B | 0.68792 (8) | 0.51251 (11) | 0.29107 (7) | 0.0488 (3) | |
Cl3B | 0.83732 (7) | 0.55922 (9) | 0.12642 (7) | 0.0400 (3) | |
Cl4B | 0.74566 (9) | 0.77648 (10) | 0.00260 (9) | 0.0501 (3) | |
Cl5B | 0.70173 (9) | 0.85653 (11) | 0.21603 (10) | 0.0647 (4) | |
Cl6B | 0.52623 (17) | 0.8699 (2) | 0.0840 (2) | 0.0609 (8) | 0.50 |
C1B | 0.5100 (3) | 0.6208 (3) | 0.0915 (3) | 0.0312 (9) | |
H1B | 0.4460 | 0.6647 | 0.0747 | 0.037* | |
C2B | 0.5781 (3) | 0.6426 (3) | 0.0152 (3) | 0.0306 (9) | |
H2B | 0.5410 | 0.6952 | −0.0308 | 0.037* | |
C3B | 0.6089 (3) | 0.5433 (3) | −0.0368 (3) | 0.0310 (9) | |
H3B1 | 0.6333 | 0.4843 | 0.0079 | 0.037* | |
H3B2 | 0.6663 | 0.5644 | −0.0683 | 0.037* | |
C4B | 0.4792 (3) | 0.5024 (3) | 0.1091 (3) | 0.0304 (9) | |
H4B1 | 0.4586 | 0.4988 | 0.1706 | 0.037* | |
H4B2 | 0.5394 | 0.4542 | 0.1104 | 0.037* | |
C5B | 0.5738 (3) | 0.6757 (4) | 0.1780 (3) | 0.0362 (10) | |
C6B | 0.6701 (3) | 0.6059 (4) | 0.2039 (3) | 0.0344 (10) | |
C7B | 0.7274 (3) | 0.6241 (3) | 0.1398 (3) | 0.0324 (9) | |
C8B | 0.6712 (3) | 0.7049 (3) | 0.0715 (3) | 0.0343 (9) | |
C9B | 0.6180 (3) | 0.7760 (4) | 0.1363 (3) | 0.0444 (11) | |
H9D | 0.5630 | 0.8225 | 0.1008 | 0.053* | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1A | 0.0514 (6) | 0.0324 (5) | 0.0245 (5) | −0.0025 (5) | 0.0149 (4) | −0.0003 (4) |
Cl2A | 0.0392 (6) | 0.0357 (6) | 0.0398 (6) | 0.0080 (5) | −0.0005 (4) | 0.0127 (5) |
Cl3A | 0.0473 (6) | 0.0243 (5) | 0.0446 (6) | 0.0049 (5) | 0.0217 (5) | −0.0033 (4) |
Cl4A | 0.0297 (5) | 0.0500 (7) | 0.0331 (5) | −0.0137 (5) | 0.0057 (4) | −0.0082 (5) |
Cl5A | 0.0406 (6) | 0.0562 (7) | 0.0428 (6) | −0.0200 (5) | 0.0212 (5) | −0.0039 (5) |
Cl6A | 0.0289 (10) | 0.0275 (10) | 0.0519 (13) | 0.0056 (8) | 0.0154 (9) | 0.0000 (9) |
C1A | 0.0272 (18) | 0.0192 (19) | 0.025 (2) | 0.0036 (16) | 0.0068 (15) | 0.0029 (15) |
C2A | 0.0234 (18) | 0.0228 (19) | 0.0222 (19) | 0.0048 (16) | 0.0031 (15) | −0.0005 (15) |
C3A | 0.0278 (19) | 0.024 (2) | 0.0225 (19) | −0.0043 (16) | 0.0055 (15) | 0.0007 (16) |
C4A | 0.034 (2) | 0.026 (2) | 0.0194 (19) | −0.0004 (17) | 0.0010 (16) | 0.0025 (16) |
C5A | 0.033 (2) | 0.024 (2) | 0.0217 (19) | 0.0011 (17) | 0.0105 (16) | 0.0037 (16) |
C6A | 0.0250 (19) | 0.024 (2) | 0.031 (2) | −0.0031 (16) | 0.0074 (16) | 0.0079 (16) |
C7A | 0.0302 (19) | 0.0164 (18) | 0.029 (2) | −0.0018 (16) | 0.0139 (16) | −0.0012 (15) |
C8A | 0.0234 (18) | 0.028 (2) | 0.0231 (19) | −0.0042 (16) | 0.0059 (15) | −0.0017 (16) |
C9A | 0.0264 (19) | 0.031 (2) | 0.031 (2) | 0.0052 (17) | 0.0111 (16) | 0.0046 (17) |
Cl1B | 0.0337 (6) | 0.0861 (10) | 0.0536 (8) | 0.0007 (6) | 0.0119 (5) | −0.0381 (7) |
Cl2B | 0.0441 (6) | 0.0722 (9) | 0.0271 (6) | 0.0022 (6) | −0.0024 (5) | 0.0005 (5) |
Cl3B | 0.0233 (5) | 0.0504 (7) | 0.0458 (6) | 0.0043 (5) | 0.0042 (4) | −0.0118 (5) |
Cl4B | 0.0484 (7) | 0.0451 (7) | 0.0570 (8) | −0.0176 (6) | 0.0088 (5) | −0.0010 (6) |
Cl5B | 0.0413 (6) | 0.0622 (8) | 0.0884 (10) | −0.0096 (6) | 0.0042 (6) | −0.0458 (8) |
Cl6B | 0.0358 (12) | 0.0373 (13) | 0.100 (2) | 0.0108 (10) | −0.0158 (12) | −0.0205 (13) |
C1B | 0.0195 (18) | 0.040 (2) | 0.032 (2) | 0.0056 (18) | −0.0011 (16) | −0.0101 (19) |
C2B | 0.0257 (19) | 0.030 (2) | 0.034 (2) | 0.0015 (17) | −0.0028 (17) | −0.0019 (17) |
C3B | 0.0255 (19) | 0.038 (2) | 0.028 (2) | −0.0051 (18) | 0.0023 (16) | −0.0041 (18) |
C4B | 0.0238 (19) | 0.042 (2) | 0.025 (2) | −0.0002 (18) | 0.0016 (15) | −0.0035 (18) |
C5B | 0.0232 (19) | 0.048 (3) | 0.038 (2) | 0.0026 (19) | 0.0056 (17) | −0.016 (2) |
C6B | 0.027 (2) | 0.050 (3) | 0.024 (2) | 0.0022 (19) | −0.0012 (16) | −0.0133 (19) |
C7B | 0.0218 (19) | 0.041 (2) | 0.033 (2) | 0.0013 (18) | −0.0002 (16) | −0.0141 (19) |
C8B | 0.029 (2) | 0.033 (2) | 0.039 (2) | −0.0032 (18) | 0.0017 (18) | −0.0076 (19) |
C9B | 0.031 (2) | 0.041 (3) | 0.058 (3) | 0.006 (2) | −0.004 (2) | −0.017 (2) |
Cl1A—C5A | 1.751 (4) | Cl1B—C5B | 1.761 (4) |
Cl2A—C6A | 1.710 (4) | Cl2B—C6B | 1.698 (4) |
Cl3A—C7A | 1.696 (4) | Cl3B—C7B | 1.701 (4) |
Cl4A—C8A | 1.763 (4) | Cl4B—C8B | 1.760 (4) |
Cl5A—C9A | 1.769 (4) | Cl5B—C9B | 1.772 (4) |
Cl6A—C9A | 1.720 (4) | Cl6B—C9B | 1.752 (5) |
C1A—C4A | 1.515 (5) | C1B—C4B | 1.527 (6) |
C1A—C5A | 1.570 (5) | C1B—C5B | 1.559 (5) |
C1A—C2A | 1.584 (5) | C1B—C2B | 1.579 (5) |
C1A—H1A | 1.0000 | C1B—H1B | 1.0000 |
C2A—C3A | 1.533 (5) | C2B—C3B | 1.518 (5) |
C2A—C8A | 1.558 (5) | C2B—C8B | 1.567 (5) |
C2A—H2A | 1.0000 | C2B—H2B | 1.0000 |
C3A—C4Ai | 1.544 (5) | C3B—C4Bii | 1.551 (5) |
C3A—H3A1 | 0.9900 | C3B—H3B1 | 0.9900 |
C3A—H3A2 | 0.9900 | C3B—H3B2 | 0.9900 |
C4A—C3Ai | 1.544 (5) | C4B—C3Bii | 1.551 (5) |
C4A—H4A1 | 0.9900 | C4B—H4B1 | 0.9900 |
C4A—H4A2 | 0.9900 | C4B—H4B2 | 0.9900 |
C5A—C6A | 1.518 (5) | C5B—C9B | 1.524 (7) |
C5A—C9A | 1.548 (5) | C5B—C6B | 1.531 (6) |
C6A—C7A | 1.324 (5) | C6B—C7B | 1.328 (5) |
C7A—C8A | 1.512 (5) | C7B—C8B | 1.511 (6) |
C8A—C9A | 1.533 (5) | C8B—C9B | 1.542 (6) |
C4A—C1A—C5A | 112.7 (3) | C4B—C1B—C5B | 112.8 (3) |
C4A—C1A—C2A | 117.6 (3) | C4B—C1B—C2B | 118.7 (3) |
C5A—C1A—C2A | 101.6 (3) | C5B—C1B—C2B | 102.2 (3) |
C4A—C1A—H1A | 108.1 | C4B—C1B—H1B | 107.5 |
C5A—C1A—H1A | 108.1 | C5B—C1B—H1B | 107.5 |
C2A—C1A—H1A | 108.1 | C2B—C1B—H1B | 107.5 |
C3A—C2A—C8A | 112.0 (3) | C3B—C2B—C8B | 113.2 (3) |
C3A—C2A—C1A | 118.2 (3) | C3B—C2B—C1B | 117.4 (3) |
C8A—C2A—C1A | 102.2 (3) | C8B—C2B—C1B | 101.6 (3) |
C3A—C2A—H2A | 108.0 | C3B—C2B—H2B | 108.1 |
C8A—C2A—H2A | 108.0 | C8B—C2B—H2B | 108.1 |
C1A—C2A—H2A | 108.0 | C1B—C2B—H2B | 108.1 |
C2A—C3A—C4Ai | 114.1 (3) | C2B—C3B—C4Bii | 113.1 (3) |
C2A—C3A—H3A1 | 108.7 | C2B—C3B—H3B1 | 109.0 |
C4Ai—C3A—H3A1 | 108.7 | C4Bii—C3B—H3B1 | 109.0 |
C2A—C3A—H3A2 | 108.7 | C2B—C3B—H3B2 | 109.0 |
C4Ai—C3A—H3A2 | 108.7 | C4Bii—C3B—H3B2 | 109.0 |
H3A1—C3A—H3A2 | 107.6 | H3B1—C3B—H3B2 | 107.8 |
C1A—C4A—C3Ai | 113.6 (3) | C1B—C4B—C3Bii | 114.4 (3) |
C1A—C4A—H4A1 | 108.8 | C1B—C4B—H4B1 | 108.7 |
C3Ai—C4A—H4A1 | 108.8 | C3Bii—C4B—H4B1 | 108.7 |
C1A—C4A—H4A2 | 108.8 | C1B—C4B—H4B2 | 108.7 |
C3Ai—C4A—H4A2 | 108.8 | C3Bii—C4B—H4B2 | 108.7 |
H4A1—C4A—H4A2 | 107.7 | H4B1—C4B—H4B2 | 107.6 |
C6A—C5A—C9A | 99.3 (3) | C9B—C5B—C6B | 100.3 (3) |
C6A—C5A—C1A | 107.5 (3) | C9B—C5B—C1B | 101.9 (3) |
C9A—C5A—C1A | 101.4 (3) | C6B—C5B—C1B | 106.8 (3) |
C6A—C5A—Cl1A | 116.0 (3) | C9B—C5B—Cl1B | 116.3 (3) |
C9A—C5A—Cl1A | 116.2 (2) | C6B—C5B—Cl1B | 115.8 (3) |
C1A—C5A—Cl1A | 114.4 (3) | C1B—C5B—Cl1B | 114.0 (3) |
C7A—C6A—C5A | 107.6 (3) | C7B—C6B—C5B | 106.7 (4) |
C7A—C6A—Cl2A | 127.4 (3) | C7B—C6B—Cl2B | 128.5 (3) |
C5A—C6A—Cl2A | 124.5 (3) | C5B—C6B—Cl2B | 124.3 (3) |
C6A—C7A—C8A | 107.1 (3) | C6B—C7B—C8B | 107.5 (3) |
C6A—C7A—Cl3A | 127.7 (3) | C6B—C7B—Cl3B | 127.8 (4) |
C8A—C7A—Cl3A | 124.8 (3) | C8B—C7B—Cl3B | 124.4 (3) |
C7A—C8A—C9A | 100.6 (3) | C7B—C8B—C9B | 100.3 (3) |
C7A—C8A—C2A | 107.6 (3) | C7B—C8B—C2B | 107.5 (3) |
C9A—C8A—C2A | 101.5 (3) | C9B—C8B—C2B | 101.2 (3) |
C7A—C8A—Cl4A | 116.0 (3) | C7B—C8B—Cl4B | 116.0 (3) |
C9A—C8A—Cl4A | 116.2 (3) | C9B—C8B—Cl4B | 116.2 (3) |
C2A—C8A—Cl4A | 113.3 (3) | C2B—C8B—Cl4B | 113.8 (3) |
C8A—C9A—C5A | 92.6 (3) | C5B—C9B—C8B | 92.9 (3) |
C8A—C9A—Cl6A | 114.9 (3) | C5B—C9B—Cl6B | 114.1 (3) |
C5A—C9A—Cl6A | 119.6 (3) | C8B—C9B—Cl6B | 116.7 (3) |
C8A—C9A—Cl5A | 115.0 (3) | C5B—C9B—Cl5B | 114.6 (3) |
C5A—C9A—Cl5A | 114.2 (3) | C8B—C9B—Cl5B | 114.5 (3) |
Cl6A—C9A—Cl5A | 101.4 (2) | Cl6B—C9B—Cl5B | 104.5 (2) |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
C1B—H1B···Cl4Aiii | 1.00 | 2.70 | 3.656 (4) | 160 |
Symmetry code: (iii) x, −y+3/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C18H13Cl11 |
Mr | 619.23 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 150 |
a, b, c (Å) | 13.3129 (5), 12.1263 (6), 14.7229 (7) |
β (°) | 99.505 (3) |
V (Å3) | 2344.18 (18) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.31 |
Crystal size (mm) | 0.26 × 0.20 × 0.15 |
Data collection | |
Diffractometer | Bruker–Nonius KappaCCD diffractometer |
Absorption correction | Multi-scan (SORTAV; Blessing, 1995) |
Tmin, Tmax | 0.715, 0.825 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15654, 5338, 3481 |
Rint | 0.052 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.050, 0.118, 1.05 |
No. of reflections | 5338 |
No. of parameters | 272 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.53, −0.68 |
Computer programs: COLLECT (Nonius, 2002), DENZO–SMN (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
C1B—H1B···Cl4Ai | 1.00 | 2.70 | 3.656 (4) | 160 |
Symmetry code: (i) x, −y+3/2, z−1/2. |
Acknowledgements
The authors acknowledge NSERC Canada and the University of Toronto for funding.
References
Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435. CrossRef Web of Science IUCr Journals Google Scholar
Blessing, R. H. (1995). Acta Cryst. A51, 33–38. CrossRef CAS Web of Science IUCr Journals Google Scholar
Nonius (2002). COLLECT. Nonius BV, Delft, The Netherlands. Google Scholar
Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press. Google Scholar
Riddell, N., McCrindle, R., Arsenault, G. & Lough, A. J. (2008). Acta Cryst. E64, o1249. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. 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.
For background information and related references see the previous paper (Riddell et al., 2008). Dechlorane Plus (DP) is a commercial chlorinated flame retardant used in styrenic plastics (http://www.inchem.org/documents/ehc/ehc/ehc192.htm) to protect human life and property against fires. We have synthesized the dechlorinated compound (1R,2R,5R,6S,9R,10S,13S,14S,18R)-1,6,7,8,9,14,15,16,17,17,18- undecachloropentacyclo[12.2.1.16,9.02,13.05,10]-octadeca-7,15-diene. GC/MS and 1H NMR spectroscopy have confirmed the basic structure of as having the DP-like structure with only 11 chlorine atoms. An NOE NMR experiment also strongly indicated that the proton on the bridging carbon atom was facing towards the cyclooctadiene ring since a positive through space interaction was observed. However, an X-ray structure determination was required to positively confirm the stereochemistry.
The asymmetric unit contains two independent half molecules. The symmetry complete molecules are generated by crystallographic inversion symmetry, causing atoms Cl6A and Cl6B, as well as the H atoms bonded to C9A and C9B to be disordered over two sites with equal occupancies. In both independent molecules the geometric parameters are the same within experimental error. The asymmetric unit is shown in Fig. 2. In the crystal structure there is a single weak intermolecular C—H···Cl interaction (Table 1).