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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o960
doi:10.1107/S1600536811010257

(S)-4-(2-Chloro­propan-2-yl)-1-(2,2,2-tri­chloro­eth­yl)cyclo­hexene

Brahim Boualy,a Mohamed Anoir Harrad,a Larbi El Firdoussi,a Mustapha Ait Alia and Corrado Rizzolib*

aEquipe de Chimie de Coordination et Catalyse, Faculté des Sciences-Semlalia, BP 2390, 40001 Marrakech, Morocco, and bDipartimento di Chimica Generale ed Inorganica, Chimica Analitica, Chimica Fisica, Universitá degli Studi di Parma, Viale G. P. Usberti 17/A, I-43124 Parma, Italy
*Correspondence e-mail: corrado.rizzoli@unipr.it

(Received 14 March 2011; accepted 18 March 2011; online 23 March 2011)

The title compound, C11H16Cl4, was synthesized by the reaction of (1S)-β-pinene with triethyl­amine in the presence of ZnCl2. The cyclo­hexene ring assumes a half-boat conformation. The crystal packing is governed only by van der Waals inter­actions. The structure, which has been refined in P21, presents a striking P21/m pseudosymmetry.

Related literature

For background to the synthesis of polyhalogenated compounds, see: Delaude et al. (2004[Delaude, L., Demonceau, A. & Noels, A. F. (2004). Top. Organomet. Chem. 11, 155-171.]); Borguet et al. (2007[Borguet, Y., Richel, A., Delfosse, S., Leclerc, A., Delaude, L. & Demonceau, A. (2007). Tetrahedron Lett. 48, 6334-6338.]). For the synthesis and structure of natural chlorinated compounds reported by our group, see: Ziyat et al. (2002[Ziyat, H., Ait Itto, M. Y., Ait Ali, M., Karim, A., Riahi, A. & Daran, J.-C. (2002). Acta Cryst. C58, o90-o93.], 2004[Ziyat, H., El Houssame, S., Ait Ali, M., Ait Itto, M. Y., Karim, A., Wartchow, R. & Butenschën, H. (2004). Z. Naturforsch. Teil B, 59, 1177-1179.]); Boualy et al. (2009[Boualy, B., El Firdoussi, L., Ait Ali, M., Karim, A. & Spannenberg, A. (2009). Z. Kristallogr. New Cryst. Struct. 224, 1-2.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data

  • C11H16Cl4

  • Mr = 290.04

  • Monoclinic, P 21

  • a = 10.6558 (7) Å

  • b = 10.3017 (6) Å

  • c = 6.3119 (3) Å

  • β = 91.251 (5)°

  • V = 692.71 (7) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 7.50 mm−1

  • T = 294 K

  • 0.21 × 0.09 × 0.07 mm
Data collection

  • Siemens AED diffractometer

  • Absorption correction: refined from ΔF (DIFABS; Walker & Stuart, 1983[Walker, N. & Stuart, D. (1983). Acta Cryst. A39, 158-166.]) Tmin = 0.456, Tmax = 0.601

  • 2764 measured reflections

  • 2528 independent reflections

  • 2206 reflections with I > 2σ(I)

  • Rint = 0.038

  • 3 standard reflections every 100 reflections intensity decay: 0.02%
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.129

  • S = 1.16

  • 2528 reflections

  • 136 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.22 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]); 1188 Friedel pairs

  • Flack parameter: −0.04 (3)

Data collection: AED (Belletti et al., 1993[Belletti, D., Cantoni, A. & Pasquinelli, G. (1993). AED. Internal Report 1/93. Centro di Studio per la Strutturistica Diffrattometrica del CNR, Parma, Italy.]); cell refinement: AED; data reduction: AED; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and SCHAKAL97 (Keller, 1997[Keller, E. (1997). SCHAKAL97. University of Freiburg, Germany.]); software used to prepare material for publication: SHELXL97 and PARST95 (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811010257/bg2395sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811010257/bg2395Isup2.hkl

checkCIF report


Comment top

The research on polyhalogenated alkanes, lactams and lactones, which are versatile intermediates in the synthesis of natural products and bioactive molecules, has held the attention of chemists for many years (Delaude et al., 2004). Among others, the Kharasch reaction is an effective method for the formation of these polyhalogenated products. This process consists in the addition of a polyhalogenated alkane to an alkene and requires either a radical initiator or a transition metal catalyst (Borguet et al., 2007). In the course of our ongoing research program aimed at the synthesis of natural chlorinated compounds (Ziyat et al., 2002; Ziyat et al., 2004; Boualy et al., 2009), the title compound has been obtained and its crystal structure is reported herein.

In the molecule of the title compound (Fig. 1) all bond lengths (Allen et al., 1987) and angles are normal. The cyclohexene ring assumes a half-boat conformation, with puckering parameters Q, θ and ϕ of 0.493 (4) Å, 51.9 (4)° and -142.0 (6)°, respectively (Cremer & Pople, 1975). The crystal structure (Fig. 2) is stabilized only by van der Waals interactions. The shortest intermolecular Cl···Cl separation observed is 3.5306 (11) Å (Cl2···Cl4i; symmetry code: (i) 1 + x, y, -1 + z). The structure, which has been refined in P21, presents a striking P21/m pseudosymmetry (See refinement section for details).

Related literature top

For background to the synthesis of polyhalogenated compounds, see: Delaude et al. (2004); Borguet et al. (2007). For the synthesis and structure of natural chlorinated compounds reported by our group, see: Ziyat et al. (2002, 2004); Boualy et al. (2009). For bond-length data, see: Allen et al. (1987). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

A mixture of (1S)-β-pinene (1 g, 7.34 mmol) and triethylamine (1 ml, 7.11 mmol) in carbon tetrachloride (15 ml) was added to a solution of ZnCl2 in (1.1 g, 8.09 mmol) in water (15 ml) under stirring at room temperature. On completion of the reaction, the mixture was diluted with 25 ml of water, extracted with carbon tetrachloride (3 × 10 ml) and dried over Na2SO4. The title compound was isolated as a white powder by column chromatography on silica gel using n-hexane as eluent (yield 90%; m. p. = 48 °C), but colourless single crystals suitable for X-ray analysis were obtained by slow evaporation of a n-hexane solution. 1H NMR (300 MHz, CDCl3): δ p.p.m. 5.71 (m, 1H), 3.28 (s, 2H), 2.29 (m, 3H), 1.97 (m, 2H), 1.65 (m, 1H), 1.53 (s, 3H), 1.54 (s, 3H). 13C NMR (75 MHz, CDCl3): δ p.p.m. 131.03 (Cq), 130.53 (CH═C), 99.06 (CCl3), 73.09 (CCl), 62.02 (CH2–CCl3), 45.73 (CH), 30.61 (CH2), 29.83 (CH3), 29.76 (CH3), 28.19 (CH2), 24.56 (CH2).

Refinement top

The molecule contains one chiral carbon atom at C4. Irrespective of this it is possible to solve the structure in the higher symmetry P21/m space group, but this forces the molecule to have a crystallographically imposed mirror symmetry passing through C1 and C4 of the cyclohexene ring, resulting in the C2 (sp2) and C6 (sp3) carbon atoms to be symmetry-related and disordered over two orientations. This disorder is totally absent in the noncentrosymmetric P21 space group. Moreover, refining in P21/m results in significantly worse R values (R1 = 5.4%, wR2 = 18.2%). All H atoms were calculated geometrically and refined using a riding model, with C—H = 0.93–0.98 Å and with Uiso(H) = 1.2 Ueq(C) or 1.5 Ueq(C) for methyl H atoms.

Computing details top

Data collection: AED (Belletti et al., 1993); cell refinement: AED (Belletti et al., 1993); data reduction: AED (Belletti et al., 1993); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and SCHAKAL97 (Keller, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PARST95 (Nardelli, 1995).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.
[Figure 2] Fig. 2. Crystal packing of the title compound approximately viewed along the a axis.
(S)-4-(2-Chloropropan-2-yl)-1-(2,2,2-trichloroethyl)cyclohexene top
Crystal data top
C11H16Cl4F(000) = 300
Mr = 290.04Dx = 1.391 Mg m−3
Monoclinic, P21Cu Kα radiation, λ = 1.54178 Å
Hall symbol: P 2ybCell parameters from 48 reflections
a = 10.6558 (7) Åθ = 19.3–31.4°
b = 10.3017 (6) ŵ = 7.50 mm−1
c = 6.3119 (3) ÅT = 294 K
β = 91.251 (5)°Irregular block, colourless
V = 692.71 (7) Å30.21 × 0.09 × 0.07 mm
Z = 2
Data collection top
Siemens AED
diffractometer		2206 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.038
Graphite monochromatorθmax = 68.0°, θmin = 4.2°
θ/2θ scansh = −12→12
Absorption correction: part of the refinement model (ΔF)
(DIFABS; Walker & Stuart, 1983)		k = −12→12
Tmin = 0.456, Tmax = 0.601l = −1→7
2764 measured reflections3 standard reflections every 100 reflections
2528 independent reflections intensity decay: 0.02%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.129 w = 1/[σ2(Fo2) + (0.0811P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.16(Δ/σ)max < 0.001
2528 reflectionsΔρmax = 0.27 e Å−3
136 parametersΔρmin = −0.22 e Å−3
1 restraintAbsolute structure: Flack (1983); 1188 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: −0.04 (3)
Crystal data top
C11H16Cl4V = 692.71 (7) Å3
Mr = 290.04Z = 2
Monoclinic, P21Cu Kα radiation
a = 10.6558 (7) ŵ = 7.50 mm−1
b = 10.3017 (6) ÅT = 294 K
c = 6.3119 (3) Å0.21 × 0.09 × 0.07 mm
β = 91.251 (5)°
Data collection top
Siemens AED
diffractometer		2206 reflections with I > 2σ(I)
Absorption correction: part of the refinement model (ΔF)
(DIFABS; Walker & Stuart, 1983)		Rint = 0.038
Tmin = 0.456, Tmax = 0.6013 standard reflections every 100 reflections
2764 measured reflections intensity decay: 0.02%
2528 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.129Δρmax = 0.27 e Å−3
S = 1.16Δρmin = −0.22 e Å−3
2528 reflectionsAbsolute structure: Flack (1983); 1188 Friedel pairs
136 parametersAbsolute structure parameter: −0.04 (3)
1 restraint
Special details top

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 (Å2) top
xyzUiso*/Ueq
Cl10.92140 (14)0.06856 (10)−0.3180 (2)0.0976 (4)
Cl21.15231 (7)0.20291 (18)−0.23878 (15)0.0990 (3)
Cl30.92735 (12)0.34740 (9)−0.3247 (2)0.0954 (4)
Cl40.46844 (7)0.21653 (15)0.60646 (11)0.0855 (3)
C10.8287 (2)0.2091 (4)0.1030 (4)0.0667 (6)
C20.7742 (4)0.1006 (3)0.1658 (7)0.0733 (9)
H20.82130.02470.16300.088*
C30.6416 (4)0.0915 (3)0.2416 (7)0.0762 (11)
H3A0.64360.07130.39170.091*
H3B0.59960.02050.16830.091*
C40.5658 (2)0.2149 (4)0.2064 (4)0.0630 (5)
H40.54600.21890.05420.076*
C50.6483 (4)0.3326 (4)0.2565 (7)0.0766 (11)
H5A0.59940.41140.23820.092*
H5B0.67760.32850.40290.092*
C60.7592 (5)0.3362 (4)0.1129 (8)0.0912 (13)
H6A0.81670.40320.16210.109*
H6B0.73020.3596−0.02880.109*
C70.9642 (2)0.2108 (5)0.0397 (4)0.0721 (6)
H7A1.00630.13700.10520.086*
H7B1.00310.28870.09710.086*
C80.9870 (2)0.2066 (5)−0.1959 (4)0.0696 (6)
C90.4387 (2)0.2159 (4)0.3195 (4)0.0657 (6)
C100.3606 (4)0.3349 (4)0.2697 (7)0.0826 (11)
H10A0.40880.41150.30140.124*
H10B0.28660.33410.35390.124*
H10C0.33670.33470.12220.124*
C110.3614 (5)0.0931 (4)0.2681 (8)0.0870 (13)
H11A0.41090.01750.30010.131*
H11B0.33790.09290.12040.131*
H11C0.28720.09240.35180.131*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1090 (9)0.0869 (6)0.0972 (9)−0.0153 (6)0.0089 (8)−0.0282 (6)
Cl20.0705 (4)0.1114 (7)0.1159 (6)0.0073 (6)0.0184 (4)0.0098 (8)
Cl30.0994 (8)0.0875 (7)0.0998 (8)0.0092 (6)0.0124 (7)0.0294 (6)
Cl40.0896 (5)0.1015 (6)0.0658 (4)−0.0017 (7)0.0100 (3)−0.0054 (6)
C10.0785 (14)0.0560 (12)0.0656 (13)0.011 (2)0.0025 (11)−0.002 (2)
C20.084 (2)0.0530 (17)0.083 (2)0.0111 (15)0.0145 (18)0.0110 (15)
C30.090 (3)0.0472 (18)0.092 (3)0.0030 (16)0.020 (2)0.0037 (17)
C40.0766 (14)0.0513 (12)0.0611 (12)0.0043 (18)0.0036 (10)0.0010 (18)
C50.079 (2)0.0523 (17)0.099 (3)−0.0007 (16)0.013 (2)−0.009 (2)
C60.091 (2)0.0473 (15)0.136 (4)0.0015 (16)0.028 (3)0.008 (2)
C70.0728 (14)0.0695 (14)0.0736 (14)0.000 (2)−0.0061 (11)0.007 (2)
C80.0673 (13)0.0629 (13)0.0787 (15)0.0014 (19)0.0050 (11)0.005 (2)
C90.0712 (14)0.0567 (13)0.0691 (13)−0.0005 (18)−0.0036 (10)−0.0042 (19)
C100.078 (3)0.071 (2)0.099 (3)0.0121 (19)0.002 (2)0.001 (2)
C110.089 (3)0.071 (3)0.100 (4)−0.007 (2)−0.001 (3)−0.008 (2)
Geometric parameters (Å, º) top
Cl1—C81.755 (4)C5—H5A0.9700
Cl2—C81.789 (3)C5—H5B0.9700
Cl3—C81.774 (4)C6—H6A0.9700
Cl4—C91.832 (3)C6—H6B0.9700
C1—C21.324 (5)C7—C81.512 (4)
C1—C61.506 (5)C7—H7A0.9700
C1—C71.507 (4)C7—H7B0.9700
C2—C31.504 (6)C9—C101.511 (5)
C2—H20.9300C9—C111.541 (6)
C3—C41.520 (5)C10—H10A0.9600
C3—H3A0.9700C10—H10B0.9600
C3—H3B0.9700C10—H10C0.9600
C4—C51.526 (5)C11—H11A0.9600
C4—C91.545 (4)C11—H11B0.9600
C4—H40.9800C11—H11C0.9600
C5—C61.505 (6)
C2—C1—C6120.1 (3)C1—C7—C8115.8 (2)
C2—C1—C7121.2 (4)C1—C7—H7A108.3
C6—C1—C7118.5 (4)C8—C7—H7A108.3
C1—C2—C3124.7 (3)C1—C7—H7B108.3
C1—C2—H2117.7C8—C7—H7B108.3
C3—C2—H2117.7H7A—C7—H7B107.4
C2—C3—C4113.6 (3)C7—C8—Cl1112.6 (3)
C2—C3—H3A108.8C7—C8—Cl3111.3 (3)
C4—C3—H3A108.8Cl1—C8—Cl3109.02 (15)
C2—C3—H3B108.8C7—C8—Cl2109.21 (18)
C4—C3—H3B108.8Cl1—C8—Cl2107.5 (2)
H3A—C3—H3B107.7Cl3—C8—Cl2107.0 (2)
C3—C4—C5109.4 (2)C10—C9—C11109.4 (2)
C3—C4—C9114.0 (3)C10—C9—C4113.2 (3)
C5—C4—C9113.9 (3)C11—C9—C4111.5 (3)
C3—C4—H4106.3C10—C9—Cl4106.6 (2)
C5—C4—H4106.3C11—C9—Cl4106.9 (3)
C9—C4—H4106.3C4—C9—Cl4108.81 (17)
C6—C5—C4110.5 (3)C9—C10—H10A109.5
C6—C5—H5A109.5C9—C10—H10B109.5
C4—C5—H5A109.5H10A—C10—H10B109.5
C6—C5—H5B109.5C9—C10—H10C109.5
C4—C5—H5B109.5H10A—C10—H10C109.5
H5A—C5—H5B108.1H10B—C10—H10C109.5
C5—C6—C1113.4 (3)C9—C11—H11A109.5
C5—C6—H6A108.9C9—C11—H11B109.5
C1—C6—H6A108.9H11A—C11—H11B109.5
C5—C6—H6B108.9C9—C11—H11C109.5
C1—C6—H6B108.9H11A—C11—H11C109.5
H6A—C6—H6B107.7H11B—C11—H11C109.5

Experimental details

Crystal data
Chemical formulaC11H16Cl4
Mr290.04
Crystal system, space groupMonoclinic, P21
Temperature (K)294
a, b, c (Å)10.6558 (7), 10.3017 (6), 6.3119 (3)
β (°) 91.251 (5)
V (Å3)692.71 (7)
Z2
Radiation typeCu Kα
µ (mm−1)7.50
Crystal size (mm)0.21 × 0.09 × 0.07
Data collection
DiffractometerSiemens AED
diffractometer
Absorption correctionPart of the refinement model (ΔF)
(DIFABS; Walker & Stuart, 1983)
Tmin, Tmax0.456, 0.601
No. of measured, independent and
observed [I > 2σ(I)] reflections		2764, 2528, 2206
Rint0.038
(sin θ/λ)max (Å−1)0.601
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.129, 1.16
No. of reflections2528
No. of parameters136
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.27, −0.22
Absolute structureFlack (1983); 1188 Friedel pairs
Absolute structure parameter−0.04 (3)

Computer programs: AED (Belletti et al., 1993), SIR97 (Altomare et al., 1999), ORTEP-3 for Windows (Farrugia, 1997) and SCHAKAL97 (Keller, 1997), SHELXL97 (Sheldrick, 2008) and PARST95 (Nardelli, 1995).

 

Acknowledgements

Financial support from the Universitá degli Studi di Parma is gratefully acknowledged.

References

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ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o960
doi:10.1107/S1600536811010257
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