Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536801016762/na6094sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536801016762/na6094Isup2.hkl |
CCDC reference: 176012
The title compound was prepared according to the procedure already reported (Aversa et al., 1982). Crystals suitable for X-ray diffraction, were obtained by slowly cooling a light petroleum solution.
Data collection: P3/V (Siemens, 1989); cell refinement: P3/V; data reduction: XDISK (Siemens, 1990); program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XPW (Siemens, 1996); software used to prepare material for publication: PARST95 (Nardelli, 1995) and SHELXL97.
Fig. 1. ORTEP (Johnson, 1976) drawing of the title molecule with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% level. |
C16H11Cl5 | F(000) = 768 |
Mr = 380.50 | Dx = 1.583 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 13.321 (3) Å | Cell parameters from 30 reflections |
b = 9.101 (2) Å | θ = 13.0–30.0° |
c = 14.279 (3) Å | µ = 0.90 mm−1 |
β = 112.77 (3)° | T = 298 K |
V = 1596.2 (6) Å3 | Regular prismatic, colourless |
Z = 4 | 0.31 × 0.20 × 0.14 mm |
Siemens R3m/V diffractometer | Rint = 0.000 |
Radiation source: fine-focus sealed tube | θmax = 24.9°, θmin = 1.7° |
Graphite monochromator | h = −15→14 |
ω–2θ scans | k = 0→10 |
2652 measured reflections | l = 0→16 |
2652 independent reflections | 3 standard reflections every 197 reflections |
1977 reflections with I > 2σ(I) | intensity decay: 1.3% |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.127 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0788P)2 + 1.718P] where P = (Fo2 + 2Fc2)/3 |
2651 reflections | (Δ/σ)max = −0.097 |
219 parameters | Δρmax = 0.52 e Å−3 |
0 restraints | Δρmin = −0.41 e Å−3 |
C16H11Cl5 | V = 1596.2 (6) Å3 |
Mr = 380.50 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 13.321 (3) Å | µ = 0.90 mm−1 |
b = 9.101 (2) Å | T = 298 K |
c = 14.279 (3) Å | 0.31 × 0.20 × 0.14 mm |
β = 112.77 (3)° |
Siemens R3m/V diffractometer | Rint = 0.000 |
2652 measured reflections | 3 standard reflections every 197 reflections |
2652 independent reflections | intensity decay: 1.3% |
1977 reflections with I > 2σ(I) |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.127 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | Δρmax = 0.52 e Å−3 |
2651 reflections | Δρmin = −0.41 e Å−3 |
219 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 on F2 for ALL reflections except for 1 with very negative F2 or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating _R_factor_obs 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) | |
Cl1 | 0.57593 (10) | 0.33146 (13) | 0.59486 (7) | 0.0686 (4) | |
Cl2 | 0.56503 (10) | 0.66582 (13) | 0.68167 (8) | 0.0703 (4) | |
Cl3 | 0.58413 (9) | 0.48844 (13) | 0.93911 (8) | 0.0671 (4) | |
Cl4 | 0.86867 (10) | 0.56966 (15) | 0.87736 (10) | 0.0777 (4) | |
Cl5 | 0.86394 (11) | 0.25868 (14) | 1.09706 (7) | 0.0780 (4) | |
C6 | 0.7897 (3) | 0.0557 (4) | 0.9475 (3) | 0.0476 (9) | |
C7 | 0.7379 (3) | 0.0184 (4) | 0.8461 (3) | 0.0517 (9) | |
H7 | 0.7324 (3) | −0.0804 (4) | 0.8280 (3) | 0.062* | |
C8 | 0.6939 (3) | 0.1226 (4) | 0.7705 (3) | 0.0518 (10) | |
H8 | 0.6591 (3) | 0.0935 (4) | 0.7031 (3) | 0.062* | |
C9 | 0.7018 (3) | 0.2693 (4) | 0.7954 (3) | 0.0523 (10) | |
C1 | 0.6507 (5) | 0.3928 (5) | 0.7197 (3) | 0.080 (2) | |
H1 | 0.7130 (5) | 0.4448 (5) | 0.7151 (3) | 0.097* | |
C2 | 0.5970 (4) | 0.5012 (6) | 0.7558 (4) | 0.047 (2) | 0.725 (8) |
H2 | 0.5276 (4) | 0.4583 (6) | 0.7507 (4) | 0.057* | 0.725 (8) |
C3 | 0.6586 (4) | 0.5459 (6) | 0.8684 (4) | 0.046 (2) | 0.725 (8) |
H3 | 0.6661 (4) | 0.6531 (6) | 0.8727 (4) | 0.055* | 0.725 (8) |
C4 | 0.7695 (6) | 0.4772 (9) | 0.9189 (6) | 0.047 (2) | 0.725 (8) |
H4 | 0.7933 (6) | 0.4910 (9) | 0.9924 (6) | 0.056* | 0.725 (8) |
C2' | 0.6734 (10) | 0.5267 (14) | 0.7414 (9) | 0.041 (4) | 0.275 (8) |
H2' | 0.7245 (10) | 0.5472 (14) | 0.7088 (9) | 0.049* | 0.275 (8) |
C3' | 0.7417 (12) | 0.5640 (15) | 0.8533 (11) | 0.048 (4) | 0.275 (8) |
H3' | 0.7196 (12) | 0.6617 (15) | 0.8670 (11) | 0.058* | 0.275 (8) |
C4' | 0.7276 (15) | 0.458 (2) | 0.9292 (16) | 0.037 (4) | 0.275 (8) |
H4' | 0.7840 (15) | 0.481 (2) | 0.9959 (16) | 0.044* | 0.275 (8) |
C10 | 0.7561 (4) | 0.3119 (4) | 0.8967 (3) | 0.0586 (11) | |
C5 | 0.7993 (3) | 0.2046 (5) | 0.9707 (3) | 0.0511 (10) | |
C11 | 0.8309 (3) | −0.0621 (4) | 1.0268 (3) | 0.0496 (9) | |
C12 | 0.9419 (4) | −0.0793 (6) | 1.0834 (3) | 0.0706 (13) | |
H12 | 0.9913 (4) | −0.0126 (6) | 1.0761 (3) | 0.085* | |
C13 | 0.9789 (4) | −0.1964 (6) | 1.1508 (4) | 0.0797 (15) | |
H13 | 1.0532 (4) | −0.2111 (6) | 1.1855 (4) | 0.096* | |
C14 | 0.9062 (5) | −0.2898 (5) | 1.1661 (3) | 0.0700 (13) | |
H14 | 0.9310 (5) | −0.3681 (5) | 1.2110 (3) | 0.084* | |
C15 | 0.7977 (4) | −0.2678 (5) | 1.1153 (3) | 0.0687 (12) | |
H15 | 0.7485 (4) | −0.3296 (5) | 1.1277 (3) | 0.082* | |
C16 | 0.7589 (4) | −0.1545 (4) | 1.0454 (3) | 0.0563 (10) | |
H16 | 0.6843 (4) | −0.1411 (4) | 1.0111 (3) | 0.068* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0868 (8) | 0.0644 (7) | 0.0342 (5) | 0.0054 (6) | 0.0010 (5) | −0.0025 (4) |
Cl2 | 0.0922 (8) | 0.0576 (7) | 0.0586 (6) | 0.0254 (6) | 0.0263 (6) | 0.0160 (5) |
Cl3 | 0.0746 (7) | 0.0740 (8) | 0.0604 (6) | 0.0085 (6) | 0.0346 (5) | 0.0007 (5) |
Cl4 | 0.0661 (7) | 0.0830 (9) | 0.0799 (8) | −0.0220 (6) | 0.0239 (6) | 0.0010 (6) |
Cl5 | 0.1006 (9) | 0.0724 (8) | 0.0351 (5) | 0.0122 (6) | −0.0020 (5) | −0.0052 (5) |
C6 | 0.045 (2) | 0.050 (2) | 0.042 (2) | 0.007 (2) | 0.012 (2) | 0.005 (2) |
C7 | 0.057 (2) | 0.041 (2) | 0.048 (2) | 0.003 (2) | 0.011 (2) | −0.004 (2) |
C8 | 0.058 (2) | 0.049 (2) | 0.037 (2) | 0.002 (2) | 0.005 (2) | −0.007 (2) |
C9 | 0.062 (2) | 0.047 (2) | 0.036 (2) | 0.010 (2) | 0.006 (2) | −0.003 (2) |
C1 | 0.117 (4) | 0.054 (3) | 0.037 (2) | 0.021 (3) | −0.008 (2) | −0.003 (2) |
C2 | 0.049 (3) | 0.051 (3) | 0.040 (3) | 0.008 (2) | 0.015 (2) | 0.005 (2) |
C3 | 0.056 (3) | 0.037 (3) | 0.046 (3) | 0.001 (2) | 0.021 (2) | 0.001 (2) |
C4 | 0.052 (5) | 0.046 (4) | 0.041 (3) | −0.007 (4) | 0.017 (3) | −0.007 (3) |
C2' | 0.036 (7) | 0.041 (8) | 0.047 (7) | 0.012 (6) | 0.017 (6) | 0.009 (6) |
C3' | 0.060 (9) | 0.028 (7) | 0.052 (8) | −0.005 (6) | 0.017 (7) | 0.003 (6) |
C4' | 0.040 (11) | 0.028 (8) | 0.047 (9) | −0.008 (8) | 0.023 (8) | 0.000 (6) |
C10 | 0.075 (3) | 0.044 (2) | 0.039 (2) | 0.010 (2) | 0.004 (2) | −0.006 (2) |
C5 | 0.053 (2) | 0.056 (2) | 0.033 (2) | 0.010 (2) | 0.004 (2) | −0.002 (2) |
C11 | 0.053 (2) | 0.050 (2) | 0.043 (2) | 0.012 (2) | 0.015 (2) | 0.003 (2) |
C12 | 0.060 (3) | 0.094 (4) | 0.055 (2) | 0.014 (2) | 0.020 (2) | 0.020 (2) |
C13 | 0.076 (3) | 0.104 (4) | 0.057 (3) | 0.031 (3) | 0.023 (2) | 0.027 (3) |
C14 | 0.105 (4) | 0.056 (3) | 0.044 (2) | 0.020 (3) | 0.023 (2) | 0.010 (2) |
C15 | 0.101 (4) | 0.053 (3) | 0.052 (2) | −0.012 (3) | 0.029 (2) | −0.001 (2) |
C16 | 0.064 (2) | 0.052 (2) | 0.051 (2) | 0.001 (2) | 0.021 (2) | −0.002 (2) |
Cl1—C1 | 1.763 (4) | C3—C4 | 1.506 (10) |
Cl2—C2 | 1.789 (5) | C3—H3 | 0.9800 |
Cl2—C2' | 1.860 (12) | C4—C10 | 1.534 (9) |
Cl3—C3 | 1.748 (5) | C4—H4 | 0.9800 |
Cl3—C4' | 1.990 (17) | C2'—C3' | 1.541 (18) |
Cl4—C3' | 1.591 (15) | C2'—H2' | 0.9800 |
Cl4—C4 | 1.847 (8) | C3'—C4' | 1.51 (2) |
Cl5—C5 | 1.743 (4) | C3'—H3' | 0.9800 |
C6—C7 | 1.384 (5) | C4'—C10 | 1.506 (19) |
C6—C5 | 1.389 (6) | C4'—H4' | 0.9800 |
C6—C11 | 1.501 (5) | C10—C5 | 1.389 (5) |
C7—C8 | 1.385 (5) | C11—C16 | 1.377 (6) |
C7—H7 | 0.9300 | C11—C12 | 1.393 (6) |
C8—C9 | 1.375 (5) | C12—C13 | 1.392 (7) |
C8—H8 | 0.9300 | C12—H12 | 0.9300 |
C9—C10 | 1.397 (5) | C13—C14 | 1.368 (7) |
C9—C1 | 1.525 (6) | C13—H13 | 0.9300 |
C1—C2' | 1.265 (14) | C14—C15 | 1.358 (7) |
C1—C2 | 1.428 (7) | C14—H14 | 0.9300 |
C1—H1 | 0.9800 | C15—C16 | 1.388 (6) |
C2—C3 | 1.549 (7) | C15—H15 | 0.9300 |
C2—H2 | 0.9800 | C16—H16 | 0.9300 |
C2—Cl2—C2' | 36.3 (4) | C1—C2'—Cl2 | 118.3 (9) |
C3—Cl3—C4' | 39.1 (6) | C3'—C2'—Cl2 | 111.5 (9) |
C3'—Cl4—C4 | 38.9 (5) | C1—C2'—H2' | 102.2 |
C7—C6—C5 | 116.8 (3) | C3'—C2'—H2' | 102.2 |
C7—C6—C11 | 120.2 (4) | Cl2—C2'—H2' | 102.2 |
C5—C6—C11 | 123.0 (3) | C4'—C3'—C2' | 114.5 (12) |
C8—C7—C6 | 122.4 (4) | C4'—C3'—Cl4 | 106.4 (11) |
C8—C7—H7 | 118.8 | C2'—C3'—Cl4 | 112.4 (10) |
C6—C7—H7 | 118.8 | C4'—C3'—H3' | 107.7 |
C9—C8—C7 | 119.7 (3) | C2'—C3'—H3' | 107.8 |
C9—C8—H8 | 120.1 | Cl4—C3'—H3' | 107.8 |
C7—C8—H8 | 120.1 | C3'—C4'—C10 | 103.1 (12) |
C8—C9—C10 | 119.6 (4) | C3'—C4'—Cl3 | 110.5 (12) |
C8—C9—C1 | 124.3 (3) | C10—C4'—Cl3 | 120.5 (10) |
C10—C9—C1 | 116.1 (4) | C3'—C4'—H4' | 107.3 |
C2'—C1—C2 | 49.6 (6) | C10—C4'—H4' | 107.3 |
C2'—C1—C9 | 122.5 (6) | Cl3—C4'—H4' | 107.3 |
C2—C1—C9 | 113.7 (4) | C5—C10—C9 | 119.2 (4) |
C2'—C1—Cl1 | 122.7 (6) | C5—C10—C4' | 117.8 (8) |
C2—C1—Cl1 | 114.7 (4) | C9—C10—C4' | 118.2 (8) |
C9—C1—Cl1 | 114.0 (3) | C5—C10—C4 | 123.4 (4) |
C2'—C1—H1 | 54.7 | C9—C10—C4 | 117.3 (4) |
C2—C1—H1 | 104.3 | C4'—C10—C4 | 24.8 (5) |
C9—C1—H1 | 104.3 | C6—C5—C10 | 122.1 (3) |
Cl1—C1—H1 | 104.3 | C6—C5—Cl5 | 119.0 (3) |
C1—C2—C3 | 114.7 (4) | C10—C5—Cl5 | 118.8 (3) |
C1—C2—Cl2 | 113.7 (4) | C16—C11—C12 | 118.8 (4) |
C3—C2—Cl2 | 107.7 (4) | C16—C11—C6 | 120.2 (3) |
C1—C2—H2 | 106.8 | C12—C11—C6 | 120.9 (4) |
C3—C2—H2 | 106.8 | C11—C12—C13 | 120.0 (5) |
Cl2—C2—H2 | 106.8 | C11—C12—H12 | 120.0 |
C4—C3—C2 | 114.6 (5) | C13—C12—H12 | 120.0 |
C4—C3—Cl3 | 105.6 (4) | C14—C13—C12 | 120.2 (5) |
C2—C3—Cl3 | 109.2 (4) | C14—C13—H13 | 119.9 |
C4—C3—H3 | 109.1 | C12—C13—H13 | 119.9 |
C2—C3—H3 | 109.1 | C15—C14—C13 | 119.7 (4) |
Cl3—C3—H3 | 109.1 | C15—C14—H14 | 120.1 |
C3—C4—C10 | 107.1 (5) | C13—C14—H14 | 120.1 |
C3—C4—Cl4 | 110.3 (5) | C14—C15—C16 | 121.1 (5) |
C10—C4—Cl4 | 114.9 (5) | C14—C15—H15 | 119.5 |
C3—C4—H4 | 108.1 | C16—C15—H15 | 119.5 |
C10—C4—H4 | 108.1 | C11—C16—C15 | 120.0 (4) |
Cl4—C4—H4 | 108.1 | C11—C16—H16 | 120.0 |
C1—C2'—C3' | 117.1 (10) | C15—C16—H16 | 120.0 |
C5—C6—C7—C8 | −2.1 (6) | Cl4—C3'—C4'—C10 | −68.5 (13) |
C11—C6—C7—C8 | 176.9 (4) | C2'—C3'—C4'—Cl3 | −73.7 (15) |
C6—C7—C8—C9 | 0.5 (6) | Cl4—C3'—C4'—Cl3 | 161.4 (8) |
C7—C8—C9—C10 | 1.2 (7) | C3—Cl3—C4'—C3' | 7.0 (7) |
C7—C8—C9—C1 | −176.2 (4) | C3—Cl3—C4'—C10 | −113.0 (17) |
C8—C9—C1—C2' | −168.6 (8) | C8—C9—C10—C5 | −1.3 (7) |
C10—C9—C1—C2' | 13.8 (10) | C1—C9—C10—C5 | 176.4 (4) |
C8—C9—C1—C2 | 135.4 (5) | C8—C9—C10—C4' | −156.2 (8) |
C10—C9—C1—C2 | −42.1 (7) | C1—C9—C10—C4' | 21.5 (9) |
C8—C9—C1—Cl1 | 1.4 (7) | C8—C9—C10—C4 | 175.7 (5) |
C10—C9—C1—Cl1 | −176.1 (4) | C1—C9—C10—C4 | −6.6 (7) |
C2'—C1—C2—C3 | −71.7 (8) | C3'—C4'—C10—C5 | 151.4 (9) |
C9—C1—C2—C3 | 41.7 (7) | Cl3—C4'—C10—C5 | −85.0 (13) |
Cl1—C1—C2—C3 | 175.3 (4) | C3'—C4'—C10—C9 | −53.4 (13) |
C2'—C1—C2—Cl2 | 52.8 (8) | Cl3—C4'—C10—C9 | 70.3 (14) |
C9—C1—C2—Cl2 | 166.2 (4) | C3'—C4'—C10—C4 | 41.1 (17) |
Cl1—C1—C2—Cl2 | −60.2 (6) | Cl3—C4'—C10—C4 | 165 (3) |
C2'—Cl2—C2—C1 | −44.1 (7) | C3—C4—C10—C5 | −132.1 (5) |
C2'—Cl2—C2—C3 | 84.1 (8) | Cl4—C4—C10—C5 | 105.0 (6) |
C1—C2—C3—C4 | 4.8 (7) | C3—C4—C10—C9 | 51.0 (7) |
Cl2—C2—C3—C4 | −122.8 (5) | Cl4—C4—C10—C9 | −71.9 (6) |
C1—C2—C3—Cl3 | −113.4 (5) | C3—C4—C10—C4' | −48 (2) |
Cl2—C2—C3—Cl3 | 118.9 (3) | Cl4—C4—C10—C4' | −171 (3) |
C4'—Cl3—C3—C4 | −5.3 (11) | C7—C6—C5—C10 | 2.0 (6) |
C4'—Cl3—C3—C2 | 118.4 (10) | C11—C6—C5—C10 | −176.9 (4) |
C2—C3—C4—C10 | −49.2 (7) | C7—C6—C5—Cl5 | −179.9 (3) |
Cl3—C3—C4—C10 | 71.0 (5) | C11—C6—C5—Cl5 | 1.1 (5) |
C2—C3—C4—Cl4 | 76.4 (6) | C9—C10—C5—C6 | −0.4 (7) |
Cl3—C3—C4—Cl4 | −163.3 (3) | C4'—C10—C5—C6 | 154.6 (8) |
C3'—Cl4—C4—C3 | −8.2 (8) | C4—C10—C5—C6 | −177.2 (5) |
C3'—Cl4—C4—C10 | 113.0 (10) | C9—C10—C5—Cl5 | −178.5 (3) |
C2—C1—C2'—C3' | 85.4 (12) | C4'—C10—C5—Cl5 | −23.4 (9) |
C9—C1—C2'—C3' | −9.4 (15) | C4—C10—C5—Cl5 | 4.7 (7) |
Cl1—C1—C2'—C3' | −178.6 (8) | C7—C6—C11—C16 | −66.0 (5) |
C2—C1—C2'—Cl2 | −52.7 (7) | C5—C6—C11—C16 | 112.9 (5) |
C9—C1—C2'—Cl2 | −147.5 (6) | C7—C6—C11—C12 | 114.6 (5) |
Cl1—C1—C2'—Cl2 | 43.3 (12) | C5—C6—C11—C12 | −66.5 (5) |
C2—Cl2—C2'—C1 | 54.8 (8) | C16—C11—C12—C13 | 5.7 (7) |
C2—Cl2—C2'—C3' | −85.5 (11) | C6—C11—C12—C13 | −174.9 (4) |
C1—C2'—C3'—C4' | −28.6 (18) | C11—C12—C13—C14 | −3.8 (8) |
Cl2—C2'—C3'—C4' | 112.2 (13) | C12—C13—C14—C15 | −0.1 (8) |
C1—C2'—C3'—Cl4 | 93.0 (12) | C13—C14—C15—C16 | 2.1 (7) |
Cl2—C2'—C3'—Cl4 | −126.2 (9) | C12—C11—C16—C15 | −3.7 (6) |
C4—Cl4—C3'—C4' | 2.5 (11) | C6—C11—C16—C15 | 176.9 (4) |
C4—Cl4—C3'—C2' | −123.7 (13) | C14—C15—C16—C11 | −0.2 (6) |
C2'—C3'—C4'—C10 | 56.4 (16) |
Experimental details
Crystal data | |
Chemical formula | C16H11Cl5 |
Mr | 380.50 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 13.321 (3), 9.101 (2), 14.279 (3) |
β (°) | 112.77 (3) |
V (Å3) | 1596.2 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.90 |
Crystal size (mm) | 0.31 × 0.20 × 0.14 |
Data collection | |
Diffractometer | Siemens R3m/V diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2652, 2652, 1977 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.592 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.127, 1.01 |
No. of reflections | 2651 |
No. of parameters | 219 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.52, −0.41 |
Computer programs: P3/V (Siemens, 1989), P3/V, XDISK (Siemens, 1990), SHELXS86 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), XPW (Siemens, 1996), PARST95 (Nardelli, 1995) and SHELXL97.
Preliminary results were presented at a National Conference (Bombieri et al., 1984). The results obtained from X-ray data analysis show that the stereochemistry of this adduct in the solid state is different from that in solution, as found from NMR studies. In fact, the dissymetric distribution of Cl atoms results in severe steric interactions which appear to be released within the alicyclic moiety of the molecule, more flexible in solution, simply by a distortion of the basic half-chair conformation. In the solid state, the very strict steric rigidity requirement of the system does not allow such an accommodation and the dissymetric adduct is forced to assume a boat conformation, which minimizes steric strain and seems to better accommodate the otherwise strongly interacting c-2, c-3 and t-4 chlorine atoms. The molecule shows a disorder problem within the alicyclic ring owing to the conformational fluxion.