(1R,2R,5R,6R,9S,10S,13S,14S)-1,6,7,8,9,14,15,16,17,17-Decachloro­penta­cyclo­[12.2.1.16,9.02,13.05,10]octa­deca-7,15-diene

Nicole Riddell; Robert McCrindle; Gilles Arsenault; Alan J Lough

doi:10.1107/S1600536808016231

. 2008 Jun 13;64(Pt 7):o1249. doi: 10.1107/S1600536808016231

(1R,2R,5R,6R,9S,10S,13S,14S)-1,6,7,8,9,14,15,16,17,17-Decachloropentacyclo[12.2.1.1^6,9.0^2,13.0^5,10]octadeca-7,15-diene

Nicole Riddell ^a, Robert McCrindle ^b, Gilles Arsenault ^a, Alan J Lough ^c,^*

PMCID: PMC2961698 PMID: 21202883

Abstract

The title compound, C₁₈H₁₄Cl₁₀, is a decachlorinated commercial flame retardant. The structure determination confirms the relative stereochemistry. The central eight-membered ring is in a chair-type conformation. In the crystal structure, there are no significant intermolecular interactions and molecules are separated by normal van der Waals distances.

Related literature

For related literature, see: Garcia et al. (1991 ▶); Hoh et al. (2006 ▶); Qiu et al. (2007 ▶); Sverko et al. (2008 ▶); Tomy et al. (2007 ▶).

Experimental

Crystal data

C₁₈H₁₄Cl₁₀
M _r = 584.79
Orthorhombic,
a = 11.4341 (2) Å
b = 12.9704 (3) Å
c = 15.0389 (4) Å
V = 2230.34 (9) Å³
Z = 4
Mo Kα radiation
μ = 1.25 mm⁻¹
T = 150 (1) K
0.24 × 0.20 × 0.18 mm

Data collection

Bruker–Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SORTAV; Blessing, 1995 ▶) T _min = 0.720, T _max = 0.804
17031 measured reflections
5087 independent reflections
4585 reflections with I > 2σ(I)
R _int = 0.036

Refinement

R[F ² > 2σ(F ²)] = 0.032
wR(F ²) = 0.072
S = 1.04
5087 reflections
253 parameters
H-atom parameters constrained
Δρ_max = 0.34 e Å⁻³
Δρ_min = −0.32 e Å⁻³
Absolute structure: Flack (1983 ▶), 2207 Friedel pairs
Flack parameter: −0.01 (6)

Data collection: COLLECT (Nonius, 2002 ▶); cell refinement: 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.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808016231/bt2716sup1.cif

e-64-o1249-sup1.cif^{(18.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808016231/bt2716Isup2.hkl

e-64-o1249-Isup2.hkl^{(249.2KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge NSERC Canada and the University of Toronto for funding.

supplementary crystallographic information

Comment

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. The two major components found in the commercial material are known as syn-DP (1R,2R,5S,6S,9R,10R,13S,14S)-[1,6,7,8,9,14,15,16,17,17,18,18- decachloropentacyclo[12.2.1.16,9.02,13.05,10]-octadeca-7,15-diene] and anti-DP (1R,2R,5R,6R,9S,10S,13S,14S)-[1,6,7,8,9,14,15,16,17,17,18,18- decachloropentacyclo[12.2.1.16,9.02,13.05,10]-octadeca-7,15-diene] (see (1) and (2) respectively, Fig. 1). X-ray structure determinations have already been completed on both compounds (Garcia et al., 1991). There is growing evidence that this flame retardant is becoming a significant environmental contaminant (Hoh et al., 2006; Qiu et al., 2007; Tomy et al., 2007). 3–5 Dechlorinated DP species have also been detected in the environment (Sverko et al., 2008) although very little is known about their identity. It is important to identify these compounds if analytical chemists wish to quantify the total presence of DP, including its dechlorinated homologues, in the environment.

We have synthesized the dechlorinated compound (1R,2R,5R,6R,9S,10S,13S,14S)-1,6,7,8,9,14,15,16,17,17-decachloropentacyclo[ 12.2.1.16,9.02,13.05,10]-octadeca-7,15-diene (compound (3); see Fig. 1). GC/MS and ¹H NMR spectroscopy have confirmed the basic structure of (3) as having the DP-like structure with only 10 chlorine atoms. X-ray structure determination of (3) was required to positively confirm the relative stereochemistry.

Experimental

The synthesis of compound (3) 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 of (3) in toluene.