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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 12| December 2012| Pages o3394-o3395

(1S,3R,8R)-2,2-Di­bromo-10-bromo­methyl-3,7,7-tri­methyl­tri­cyclo­[6.4.0.01,3]dodec-9-ene

aLaboratoire de Chimie des Substances Naturelles, "Unité Associé au CNRST (URAC16)", Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco, bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Avenue Ibn Battouta, BP 1014 Rabat, Morocco, and cLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
*Correspondence e-mail: berraho@uca.ma

(Received 6 November 2012; accepted 9 November 2012; online 24 November 2012)

The title compound, C16H23Br3, was synthesized from β-himachalene (3,5,5,9-tetra­methyl-2,4a,5,6,7,8-hexa­hydro-1H-benzocyclo­heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The mol­ecule is built up from fused six- and seven-membered rings and an additional three-membered ring from the reaction of himachalene with dibromo­carbene. The six-membered ring has an envelope conformation (the flap atom being the C atom shared with the three-membered ring, whereas the seven-membered ring displays a screw boat conformation; the dihedral angle between the rings (defined by the near coplanar atoms) is 56.5 (2)°.

Related literature

For the isolation of β-himachalene, see: Joseph & Dev (1968[Joseph, T. C. & Dev, S. (1968). Tetrahedron, 24, 3841-3859.]); Plattier & Teiseire (1974[Plattier, M. & Teiseire, P. (1974). Recherche, 19, 131-144.]). For the reactivity of this sesquiterpene, see: Lassaba et al. (1997[Lassaba, E., Chekroun, A., Benharref, A., Chiaroni, A., Riche, C. & Lavergne, J.-P. (1997). Bull. Soc. Chim. Belg. 106, 281-288.]); Chekroun et al. (2000[Chekroun, A., Jarid, A., Benharref, A. & Boutalib, A. (2000). J. Org. Chem. 65, 4431-4434.]); El Jamili et al. (2002[El Jamili, H., Auhmani, A., Dakir, M., Lassaba, E., Benharref, A., Pierrot, M., Chiaroni, A. & Riche, C. (2002). Tetrahedron Lett. 43, 6645-6648.]); Sbai et al. (2002[Sbai, F., Dakir, M., Auhmani, A., El Jamili, H., Akssira, M., Benharref, A., Kenz, A. & Pierrot, M. (2002). Acta Cryst. C58, o518-o520.]); Dakir et al. (2004[Dakir, M., Auhmani, A., Ait Itto, M. Y., Mazoir, N., Akssira, M., Pierrot, M. & Benharref, A. (2004). Synth. Commun. 34, 2001-2008.]); Benharref et al. (2010[Benharref, A., El Ammari, L. & Berraho, M. (2010). Acta Cryst. E66, o2911.]). For its biological activity, see: Daoubi et al. (2004[Daoubi, M., Duran -Patron, R., Hmamouchi, M., Hernandez -Galan, R., Benharref, A. & Isidro, G. C. (2004). Pest. Manag. Sci. 60, 927-932.]). For conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C16H23Br3

  • Mr = 455.07

  • Orthorhombic, P 21 21 21

  • a = 9.2614 (5) Å

  • b = 12.8215 (8) Å

  • c = 14.3966 (11) Å

  • V = 1709.52 (19) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 7.07 mm−1

  • T = 180 K

  • 0.49 × 0.31 × 0.08 mm

Data collection
  • Agilent Xcalibur (Sapphire1, long nozzle) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010[Agilent (2010). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.135, Tmax = 1.000

  • 9721 measured reflections

  • 3461 independent reflections

  • 3121 reflections with I > 2σ(I)

  • Rint = 0.049

Refinement
  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.075

  • S = 1.04

  • 3461 reflections

  • 176 parameters

  • H-atom parameters constrained

  • Δρmax = 0.66 e Å−3

  • Δρmin = −0.55 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1460 Friedel pairs

  • Flack parameter: 0.012 (16)

Data collection: CrysAlis PRO (Agilent, 2010[Agilent (2010). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

Our work lies within the framework of the valorization of the most abundant essential oils in Morocco, such as the one from Cedrus atlantica. This oil is made up mainly (75%) of bicyclic sesquiterpenes hydrocarbons, among which is found β-himachalene (Joseph & Dev, 1968; Plattier & Teiseire, 1974). The reactivity of this sesquiterpene and its derivatives has been studied extensively by our team in order to prepare new products having biological proprieties (Lassaba et al., 1997; Chekroun et al., 2000; El Jamili et al., 2002; Sbai et al., 2002; Dakir et al., 2004; Benharref et al.,2010). Indeed, these compounds were tested, using the food poisoning technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea (Daoubi et al., 2004). In a previous work (El Jamili et al., 2002) we have prepared (1S,3R,8R)-2,2-dibromo- 3,7,7,10- tetramethyltricyclo [6.4.0.01,3] dodec-9-ene from β-himachalene, which by treatment with N-bromosuccinimide gave the title compound. The structure of this new product was determined by single-crystal X-ray structure analysis. The molecule is built up from two fused six-and seven- membered rings and an additional three-membered ring from the reaction with the carbene (Fig.1). The six-membered ring has an envelope conformation, as indicated by the total puckering amplitude QT = 0.497 (4) Å and spherical polar angle θ= 129.5 (5)° with ϕ = 149.2 (7)°, whereas the seven-membered ring displays a screw boat conformation with QT = 1.1556 (4) Å, θ = 88.2 (20)°, ϕ2 = -48.26 (20)° and ϕ3 = -117.47 (7)° (Cremer & Pople, 1975). Owing to the presence of Br atoms, the absolute configuration could be fully confirmed as C1(S), C3(R)and C8(R) by refining the Flack (1983) parameter as C1(S), C3(R)and C8(R).

Related literature top

For the isolation of β-himachalene, see: Joseph & Dev (1968); Plattier & Teiseire (1974). For the reactivity of this sesquiterpene, see: Lassaba et al. (1997); Chekroun et al. (2000); El Jamili et al. (2002); Sbai et al. (2002); Dakir et al. (2004); Benharref et al. (2010). For its biological activity, see: Daoubi et al. (2004). For conformational analysis, see: Cremer & Pople (1975).

Experimental top

In a reactor containing a solution of (1S,3R,8R)-2,2-dibromo-3,7,7,10 tetramethyltricyclo[6.4.0.01,3] dodec-9-ene (1 g, 2.6 mmol) in 50 ml of tetrahydrofuran and water (THF/H2O) (4:1) cooled to 273 K and kept in the dark, was added in small portions 1 g (5.2 mmol) of N-bromosccinimide. The reaction mixture was left stirring for 1 h, after which 20 ml of a saturated solution of NaHCO3 was added. Subsequently, the extraction was performed three times with diethyl ether (3 x 20 ml). The organic extracts were dried over Na2SO4, filtered, concentrated, and chromatographed. The title compound (1S,3R,8R)-2,2,16-tribromo-3,7,7,10-tetramethyltricyclo[6.4.0.01,3]dodec-9-ene was obtained with a yield of 16% (18 mg, 0.4 mmol) and was recrystallized from n-pentane solution at room temperature.

Refinement top

All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl), 0.97 Å (methylene) and 0.98 Å (methine) with Uiso(H) = 1.2 Ueq(methylene, methine) or Uiso(H) = 1.5 Ueq(methyl).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability. level. H atoms are represented as small spheres of arbitrary radii.
(1S,3R,8R)-2,2-Dibromo-10-bromomethyl-3,7,7- trimethyltricyclo[6.4.0.01,3]dodec-9-ene top
Crystal data top
C16H23Br3F(000) = 896
Mr = 455.07Dx = 1.768 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 3461 reflections
a = 9.2614 (5) Åθ = 3.1–26.4°
b = 12.8215 (8) ŵ = 7.07 mm1
c = 14.3966 (11) ÅT = 180 K
V = 1709.52 (19) Å3Prism, colourless
Z = 40.49 × 0.31 × 0.08 mm
Data collection top
Agilent Xcalibur (Sapphire1, long nozzle)
diffractometer
3461 independent reflections
Graphite monochromator3121 reflections with I > 2σ(I)
Detector resolution: 8.2632 pixels mm-1Rint = 0.049
ω scansθmax = 26.4°, θmin = 3.1°
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
h = 1111
Tmin = 0.135, Tmax = 1.000k = 1615
9721 measured reflectionsl = 1517
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.034 w = 1/[σ2(Fo2) + (0.0387P)2 + 0.0947P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.075(Δ/σ)max = 0.001
S = 1.04Δρmax = 0.66 e Å3
3461 reflectionsΔρmin = 0.55 e Å3
176 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0034 (4)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 1460 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.012 (16)
Crystal data top
C16H23Br3V = 1709.52 (19) Å3
Mr = 455.07Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.2614 (5) ŵ = 7.07 mm1
b = 12.8215 (8) ÅT = 180 K
c = 14.3966 (11) Å0.49 × 0.31 × 0.08 mm
Data collection top
Agilent Xcalibur (Sapphire1, long nozzle)
diffractometer
3461 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
3121 reflections with I > 2σ(I)
Tmin = 0.135, Tmax = 1.000Rint = 0.049
9721 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.075Δρmax = 0.66 e Å3
S = 1.04Δρmin = 0.55 e Å3
3461 reflectionsAbsolute structure: Flack (1983), 1460 Friedel pairs
176 parametersAbsolute structure parameter: 0.012 (16)
0 restraints
Special details top

Experimental. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. CrysAlisPro (Agilent, 2010)

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 (Å2) top
xyzUiso*/Ueq
C130.9676 (5)0.5913 (4)0.4115 (3)0.0283 (12)
H13A0.91190.62200.46060.042*
H13B0.99890.52300.42990.042*
H13C0.90930.58610.35650.042*
C11.1613 (4)0.6641 (3)0.2929 (3)0.0110 (8)
C21.0820 (5)0.7571 (3)0.3330 (3)0.0164 (9)
C31.0980 (5)0.6589 (3)0.3916 (3)0.0160 (9)
C41.2066 (6)0.6600 (3)0.4707 (3)0.0251 (11)
H4A1.15670.67460.52850.030*
H4B1.27600.71540.46020.030*
C51.2867 (6)0.5560 (4)0.4793 (3)0.0280 (12)
H5A1.22750.50820.51510.034*
H5B1.37520.56750.51390.034*
C61.3251 (5)0.5037 (3)0.3864 (3)0.0233 (10)
H6A1.23560.48180.35730.028*
H6B1.37980.44100.40010.028*
C71.4112 (5)0.5671 (3)0.3143 (3)0.0196 (10)
C81.3273 (4)0.6703 (3)0.2837 (3)0.0146 (8)
H81.35940.72610.32540.018*
C91.3668 (4)0.7037 (3)0.1861 (3)0.0186 (10)
H91.46140.72500.17560.022*
C101.2776 (5)0.7050 (3)0.1147 (3)0.0158 (9)
C111.1229 (5)0.6707 (3)0.1223 (3)0.0161 (9)
H11A1.09880.62840.06870.019*
H11B1.06110.73180.12140.019*
C121.0923 (4)0.6086 (3)0.2101 (3)0.0139 (8)
H12A1.13180.53890.20410.017*
H12B0.98890.60280.21950.017*
C141.5566 (5)0.6008 (4)0.3559 (4)0.0427 (15)
H14A1.61190.54010.37190.064*
H14B1.54000.64190.41060.064*
H14C1.60880.64150.31110.064*
C151.4416 (6)0.4939 (4)0.2310 (3)0.0328 (13)
H15A1.49330.43360.25210.049*
H15B1.49850.53030.18560.049*
H15C1.35180.47270.20360.049*
C161.3330 (6)0.7378 (4)0.0200 (3)0.0286 (11)
H16A1.31720.68170.02410.034*
H16B1.43610.75060.02360.034*
Br10.89111 (5)0.79294 (4)0.28578 (3)0.02481 (13)
Br21.17768 (6)0.88596 (3)0.36490 (3)0.02729 (14)
Br31.23443 (7)0.86490 (4)0.02407 (4)0.04212 (18)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C130.030 (3)0.028 (3)0.027 (3)0.002 (2)0.016 (2)0.009 (2)
C10.0118 (18)0.0124 (18)0.0088 (19)0.0009 (16)0.0025 (16)0.0028 (17)
C20.016 (2)0.018 (2)0.015 (2)0.0061 (18)0.0004 (17)0.0025 (18)
C30.020 (2)0.015 (2)0.013 (2)0.0007 (19)0.0037 (18)0.0005 (17)
C40.047 (3)0.021 (2)0.007 (2)0.003 (2)0.005 (2)0.0004 (18)
C50.046 (3)0.026 (2)0.013 (2)0.008 (2)0.005 (2)0.004 (2)
C60.032 (3)0.019 (2)0.020 (3)0.007 (2)0.001 (2)0.0051 (18)
C70.012 (2)0.021 (2)0.026 (3)0.0040 (19)0.0045 (18)0.0045 (19)
C80.0139 (19)0.015 (2)0.015 (2)0.0022 (17)0.0019 (19)0.0036 (18)
C90.010 (2)0.019 (2)0.026 (3)0.0017 (18)0.0026 (16)0.007 (2)
C100.021 (2)0.0145 (19)0.012 (2)0.0047 (19)0.0061 (17)0.0031 (17)
C110.020 (2)0.018 (2)0.010 (2)0.0006 (18)0.0006 (17)0.0011 (17)
C120.0130 (19)0.0158 (19)0.013 (2)0.0010 (18)0.0010 (18)0.0032 (18)
C140.020 (3)0.042 (3)0.066 (4)0.003 (2)0.022 (3)0.018 (3)
C150.029 (3)0.030 (3)0.040 (3)0.015 (2)0.009 (2)0.010 (2)
C160.033 (3)0.030 (3)0.023 (3)0.010 (2)0.011 (2)0.012 (2)
Br10.0178 (2)0.0254 (2)0.0312 (3)0.0070 (2)0.0019 (2)0.0009 (2)
Br20.0377 (3)0.0147 (2)0.0295 (3)0.0026 (2)0.0072 (2)0.0044 (2)
Br30.0431 (3)0.0365 (3)0.0467 (4)0.0046 (3)0.0065 (3)0.0243 (3)
Geometric parameters (Å, º) top
C13—C31.514 (6)C7—C151.549 (6)
C13—H13A0.9600C7—C81.596 (6)
C13—H13B0.9600C8—C91.515 (6)
C13—H13C0.9600C8—H80.9800
C1—C21.516 (6)C9—C101.318 (6)
C1—C121.528 (5)C9—H90.9300
C1—C31.540 (6)C10—C111.503 (6)
C1—C81.544 (5)C10—C161.517 (6)
C2—C31.523 (6)C11—C121.520 (6)
C2—Br21.930 (4)C11—H11A0.9700
C2—Br11.949 (4)C11—H11B0.9700
C3—C41.519 (6)C12—H12A0.9700
C4—C51.532 (6)C12—H12B0.9700
C4—H4A0.9700C14—H14A0.9600
C4—H4B0.9700C14—H14B0.9600
C5—C61.538 (6)C14—H14C0.9600
C5—H5A0.9700C15—H15A0.9600
C5—H5B0.9700C15—H15B0.9600
C6—C71.541 (6)C15—H15C0.9600
C6—H6A0.9700C16—Br31.973 (4)
C6—H6B0.9700C16—H16A0.9700
C7—C141.535 (6)C16—H16B0.9700
C3—C13—H13A109.5C14—C7—C8107.5 (4)
C3—C13—H13B109.5C6—C7—C8111.8 (3)
H13A—C13—H13B109.5C15—C7—C8112.1 (4)
C3—C13—H13C109.5C9—C8—C1109.5 (3)
H13A—C13—H13C109.5C9—C8—C7111.9 (3)
H13B—C13—H13C109.5C1—C8—C7114.7 (3)
C2—C1—C12117.5 (3)C9—C8—H8106.7
C2—C1—C359.8 (3)C1—C8—H8106.7
C12—C1—C3122.7 (3)C7—C8—H8106.7
C2—C1—C8118.3 (4)C10—C9—C8125.1 (4)
C12—C1—C8112.0 (3)C10—C9—H9117.4
C3—C1—C8117.4 (4)C8—C9—H9117.4
C1—C2—C360.9 (3)C9—C10—C11122.5 (4)
C1—C2—Br2122.8 (3)C9—C10—C16119.5 (4)
C3—C2—Br2122.1 (3)C11—C10—C16118.0 (4)
C1—C2—Br1119.5 (3)C10—C11—C12113.0 (3)
C3—C2—Br1118.5 (3)C10—C11—H11A109.0
Br2—C2—Br1107.3 (2)C12—C11—H11A109.0
C13—C3—C4113.1 (4)C10—C11—H11B109.0
C13—C3—C2120.0 (4)C12—C11—H11B109.0
C4—C3—C2118.1 (4)H11A—C11—H11B107.8
C13—C3—C1120.2 (4)C11—C12—C1109.1 (3)
C4—C3—C1116.1 (4)C11—C12—H12A109.9
C2—C3—C159.3 (3)C1—C12—H12A109.9
C3—C4—C5111.9 (4)C11—C12—H12B109.9
C3—C4—H4A109.2C1—C12—H12B109.9
C5—C4—H4A109.2H12A—C12—H12B108.3
C3—C4—H4B109.2C7—C14—H14A109.5
C5—C4—H4B109.2C7—C14—H14B109.5
H4A—C4—H4B107.9H14A—C14—H14B109.5
C4—C5—C6114.9 (4)C7—C14—H14C109.5
C4—C5—H5A108.5H14A—C14—H14C109.5
C6—C5—H5A108.5H14B—C14—H14C109.5
C4—C5—H5B108.5C7—C15—H15A109.5
C6—C5—H5B108.5C7—C15—H15B109.5
H5A—C5—H5B107.5H15A—C15—H15B109.5
C5—C6—C7118.4 (4)C7—C15—H15C109.5
C5—C6—H6A107.7H15A—C15—H15C109.5
C7—C6—H6A107.7H15B—C15—H15C109.5
C5—C6—H6B107.7C10—C16—Br3111.2 (3)
C7—C6—H6B107.7C10—C16—H16A109.4
H6A—C6—H6B107.1Br3—C16—H16A109.4
C14—C7—C6109.9 (4)C10—C16—H16B109.4
C14—C7—C15108.2 (4)Br3—C16—H16B109.4
C6—C7—C15107.2 (4)H16A—C16—H16B108.0

Experimental details

Crystal data
Chemical formulaC16H23Br3
Mr455.07
Crystal system, space groupOrthorhombic, P212121
Temperature (K)180
a, b, c (Å)9.2614 (5), 12.8215 (8), 14.3966 (11)
V3)1709.52 (19)
Z4
Radiation typeMo Kα
µ (mm1)7.07
Crystal size (mm)0.49 × 0.31 × 0.08
Data collection
DiffractometerAgilent Xcalibur (Sapphire1, long nozzle)
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2010)
Tmin, Tmax0.135, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
9721, 3461, 3121
Rint0.049
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.075, 1.04
No. of reflections3461
No. of parameters176
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.66, 0.55
Absolute structureFlack (1983), 1460 Friedel pairs
Absolute structure parameter0.012 (16)

Computer programs: CrysAlis PRO (Agilent, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS and CNRST) for the X-ray measurements.

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Volume 68| Part 12| December 2012| Pages o3394-o3395
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