



Supporting information
![]() | Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807063581/lh2578sup1.cif |
![]() | Structure factor file (CIF format) https://doi.org/10.1107/S1600536807063581/lh2578Isup2.hkl |
CCDC reference: 676159
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean
(C-C) = 0.009 Å
- R factor = 0.067
- wR factor = 0.130
- Data-to-parameter ratio = 17.5
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low .... 43 Perc. PLAT062_ALERT_4_C Rescale T(min) & T(max) by ..................... 0.88 PLAT213_ALERT_2_C Atom C2 has ADP max/min Ratio ............. 3.30 oblat PLAT230_ALERT_2_C Hirshfeld Test Diff for O4 - C8 .. 5.40 su PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for C6 PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ... 9
Alert level G ABSTM02_ALERT_3_G When printed, the submitted absorption T values will be replaced by the scaled T values. Since the ratio of scaled T's is identical to the ratio of reported T values, the scaling does not imply a change to the absorption corrections used in the study. Ratio of Tmax expected/reported 0.882 Tmax scaled 0.423 Tmin scaled 0.245 PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints ....... 29
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 6 ALERT level C = Check and explain 2 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 3 ALERT type 2 Indicator that the structure model may be wrong or deficient 4 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
The title compound was prepared by a previously reported method (Mitchell et al., 1995).
The crystals of the title compound, were obtained by dissolving (I) (2.00 g, 4.03 mmol) into acetone (50 ml), and evaporating the solvent slowly at room temperature for about 3 d.
H atoms were positioned geometrically, with C—H = 0.93 - 0.98Å and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for all other H atoms.
The molecular structure of the title compound is shown in Fig. 1. The bond lengths and angles are within normal ranges (Allen et al., 1987).
The asymmetric unit contains one half-molecule; the full molecule being generated by a crystallographic twofold rotation axis. Weak intramolecular C—H···O hydrogen bonds may, in part, control the conformation of the molecule. In the crystal structure, molecules are connected into a two-dimensional network via weak intermolecular C—H···O hydrogen bonds. (Fig. 2).
For related literature, see: Allen et al. (1987); Mitchell et al. (1995).
Data collection: CAD-4 Software (Enraf–Nonius, 1985); cell refinement: CAD-4 Software (Enraf–Nonius, 1985); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Bruker, 2000).
C16H16Br2O8 | F(000) = 984 |
Mr = 496.09 | Dx = 1.731 Mg m−3 |
Orthorhombic, Pbcn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2n 2ab | Cell parameters from 25 reflections |
a = 20.639 (4) Å | θ = 10–14° |
b = 10.150 (2) Å | µ = 4.30 mm−1 |
c = 9.0880 (18) Å | T = 298 K |
V = 1903.8 (6) Å3 | Plate, colourless |
Z = 4 | 0.40 × 0.30 × 0.20 mm |
Enraf–Nonius CAD-4 diffractometer | 805 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.054 |
Graphite monochromator | θmax = 26.0°, θmin = 2.0° |
ω/2θ scans | h = 0→25 |
Absorption correction: ψ scan (North et al., 1968) | k = 0→12 |
Tmin = 0.278, Tmax = 0.480 | l = 0→11 |
3687 measured reflections | 3 standard reflections every 200 reflections |
1877 independent reflections | intensity decay: none |
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)] = 0.067 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.130 | H-atom parameters constrained |
S = 0.96 | w = 1/[σ2(Fo2) + (0.02P)2 + 0.0P] where P = (Fo2 + 2Fc2)/3 |
1877 reflections | (Δ/σ)max = 0.001 |
107 parameters | Δρmax = 0.58 e Å−3 |
29 restraints | Δρmin = −0.49 e Å−3 |
C16H16Br2O8 | V = 1903.8 (6) Å3 |
Mr = 496.09 | Z = 4 |
Orthorhombic, Pbcn | Mo Kα radiation |
a = 20.639 (4) Å | µ = 4.30 mm−1 |
b = 10.150 (2) Å | T = 298 K |
c = 9.0880 (18) Å | 0.40 × 0.30 × 0.20 mm |
Enraf–Nonius CAD-4 diffractometer | 805 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.054 |
Tmin = 0.278, Tmax = 0.480 | 3 standard reflections every 200 reflections |
3687 measured reflections | intensity decay: none |
1877 independent reflections |
R[F2 > 2σ(F2)] = 0.067 | 29 restraints |
wR(F2) = 0.130 | H-atom parameters constrained |
S = 0.96 | Δρmax = 0.58 e Å−3 |
1877 reflections | Δρmin = −0.49 e Å−3 |
107 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 | ||
Br | 0.61944 (4) | 0.39329 (6) | 0.10603 (9) | 0.0671 (3) | |
O1 | 0.6622 (2) | 0.6733 (4) | 0.2433 (6) | 0.0456 (11) | |
O2 | 0.7386 (3) | 0.6717 (7) | 0.0680 (7) | 0.0852 (19) | |
O3 | 0.6065 (2) | 0.8406 (5) | 0.1438 (5) | 0.049 | |
O4 | 0.5702 (3) | 0.8387 (5) | −0.0882 (6) | 0.0750 (17) | |
C1 | 0.5000 | 0.4229 (8) | 0.2500 | 0.042 (2) | |
H1A | 0.5000 | 0.3313 | 0.2500 | 0.051* | |
C2 | 0.5520 (3) | 0.4888 (6) | 0.1917 (7) | 0.0390 (16) | |
C3 | 0.5535 (3) | 0.6316 (6) | 0.1962 (7) | 0.0414 (17) | |
C4 | 0.5000 | 0.6958 (9) | 0.2500 | 0.037 (2) | |
H4A | 0.5000 | 0.7874 | 0.2500 | 0.044* | |
C5 | 0.6135 (3) | 0.6973 (7) | 0.1474 (7) | 0.041 | |
H5A | 0.6256 | 0.6652 | 0.0494 | 0.049* | |
C6 | 0.7244 (4) | 0.6543 (8) | 0.1961 (9) | 0.052 (2) | |
C7 | 0.7671 (4) | 0.6004 (9) | 0.3066 (9) | 0.084 (3) | |
H7A | 0.8098 | 0.5906 | 0.2661 | 0.126* | |
H7B | 0.7513 | 0.5159 | 0.3375 | 0.126* | |
H7C | 0.7688 | 0.6588 | 0.3896 | 0.126* | |
C8 | 0.5877 (3) | 0.8970 (7) | 0.0164 (10) | 0.063 (2) | |
C9 | 0.5899 (4) | 1.0491 (6) | 0.0331 (9) | 0.060 (2) | |
H9A | 0.5761 | 1.0896 | −0.0571 | 0.090* | |
H9B | 0.6334 | 1.0762 | 0.0552 | 0.090* | |
H9C | 0.5616 | 1.0757 | 0.1116 | 0.090* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br | 0.0785 (5) | 0.0252 (4) | 0.0977 (6) | 0.0028 (4) | 0.0283 (5) | −0.0106 (5) |
O1 | 0.055 (3) | 0.033 (2) | 0.049 (3) | 0.001 (2) | −0.007 (2) | −0.009 (3) |
O2 | 0.064 (4) | 0.107 (5) | 0.084 (4) | −0.006 (4) | 0.024 (3) | −0.001 (4) |
O3 | 0.049 | 0.049 | 0.049 | 0.000 | 0.000 | 0.000 |
O4 | 0.095 (4) | 0.051 (3) | 0.080 (4) | −0.008 (3) | −0.023 (3) | 0.005 (4) |
C1 | 0.058 (5) | 0.019 (4) | 0.049 (5) | 0.000 | 0.010 (5) | 0.000 |
C2 | 0.051 (3) | 0.013 (3) | 0.053 (4) | −0.004 (3) | −0.011 (3) | −0.016 (3) |
C3 | 0.058 (4) | 0.022 (3) | 0.045 (4) | −0.005 (3) | −0.008 (3) | −0.010 (3) |
C4 | 0.051 (5) | 0.021 (4) | 0.040 (5) | 0.000 | 0.005 (4) | 0.000 |
C5 | 0.041 | 0.041 | 0.041 | 0.000 | 0.000 | 0.000 |
C6 | 0.058 (5) | 0.052 (5) | 0.046 (5) | −0.010 (4) | 0.010 (4) | −0.018 (4) |
C7 | 0.067 (5) | 0.095 (8) | 0.090 (7) | 0.020 (6) | 0.000 (5) | −0.012 (6) |
C8 | 0.037 (3) | 0.059 (5) | 0.094 (6) | 0.009 (4) | −0.011 (4) | −0.055 (6) |
C9 | 0.077 (5) | 0.018 (3) | 0.084 (5) | −0.005 (4) | 0.004 (5) | −0.001 (5) |
Br—C2 | 1.866 (6) | C3—C5 | 1.476 (9) |
O1—C5 | 1.353 (7) | C4—C3i | 1.372 (8) |
O1—C6 | 1.366 (8) | C4—H4A | 0.9300 |
O2—C6 | 1.213 (9) | C5—H5A | 0.9800 |
O3—C8 | 1.349 (9) | C6—C7 | 1.445 (10) |
O3—C5 | 1.461 (9) | C7—H7A | 0.9600 |
O4—C8 | 1.177 (8) | C7—H7B | 0.9600 |
C1—C2 | 1.371 (7) | C7—H7C | 0.9600 |
C1—C2i | 1.371 (7) | C8—C9 | 1.552 (8) |
C1—H1A | 0.9300 | C9—H9A | 0.9600 |
C2—C3 | 1.450 (8) | C9—H9B | 0.9600 |
C3—C4 | 1.372 (8) | C9—H9C | 0.9600 |
C5—O1—C6 | 121.4 (6) | C3—C5—H5A | 109.6 |
C8—O3—C5 | 118.0 (5) | O2—C6—O1 | 120.5 (7) |
C2—C1—C2i | 121.6 (8) | O2—C6—C7 | 125.0 (7) |
C2—C1—H1A | 119.2 | O1—C6—C7 | 114.1 (6) |
C2i—C1—H1A | 119.2 | C6—C7—H7A | 109.5 |
C1—C2—C3 | 119.6 (6) | C6—C7—H7B | 109.5 |
C1—C2—Br | 119.4 (4) | H7A—C7—H7B | 109.5 |
C3—C2—Br | 121.0 (5) | C6—C7—H7C | 109.5 |
C4—C3—C2 | 117.9 (6) | H7A—C7—H7C | 109.5 |
C4—C3—C5 | 124.6 (6) | H7B—C7—H7C | 109.5 |
C2—C3—C5 | 117.5 (6) | O4—C8—O3 | 124.6 (7) |
C3i—C4—C3 | 123.3 (8) | O4—C8—C9 | 126.0 (8) |
C3i—C4—H4A | 118.4 | O3—C8—C9 | 109.3 (6) |
C3—C4—H4A | 118.4 | C8—C9—H9A | 109.5 |
O1—C5—O3 | 105.5 (5) | C8—C9—H9B | 109.5 |
O1—C5—C3 | 110.4 (5) | H9A—C9—H9B | 109.5 |
O3—C5—C3 | 112.0 (5) | C8—C9—H9C | 109.5 |
O1—C5—H5A | 109.6 | H9A—C9—H9C | 109.5 |
O3—C5—H5A | 109.6 | H9B—C9—H9C | 109.5 |
C2i—C1—C2—C3 | 2.3 (4) | C8—O3—C5—O1 | 147.6 (5) |
C2i—C1—C2—Br | −177.1 (5) | C8—O3—C5—C3 | −92.3 (7) |
C1—C2—C3—C4 | −4.6 (9) | C4—C3—C5—O1 | 109.4 (6) |
Br—C2—C3—C4 | 174.8 (3) | C2—C3—C5—O1 | −68.3 (8) |
C1—C2—C3—C5 | 173.3 (5) | C4—C3—C5—O3 | −7.8 (8) |
Br—C2—C3—C5 | −7.3 (9) | C2—C3—C5—O3 | 174.5 (6) |
C2—C3—C4—C3i | 2.2 (4) | C5—O1—C6—O2 | 7.5 (12) |
C5—C3—C4—C3i | −175.5 (7) | C5—O1—C6—C7 | −166.4 (6) |
C6—O1—C5—O3 | −96.1 (7) | C5—O3—C8—O4 | 7.9 (10) |
C6—O1—C5—C3 | 142.8 (6) | C5—O3—C8—C9 | −174.6 (6) |
Symmetry code: (i) −x+1, y, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4A···O3 | 0.93 | 2.46 | 2.815 (7) | 103 |
C5—H5A···O2 | 0.98 | 2.34 | 2.693 (9) | 100 |
C7—H7C···O2ii | 0.96 | 2.37 | 3.318 (11) | 170 |
Symmetry code: (ii) −x+3/2, −y+3/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C16H16Br2O8 |
Mr | 496.09 |
Crystal system, space group | Orthorhombic, Pbcn |
Temperature (K) | 298 |
a, b, c (Å) | 20.639 (4), 10.150 (2), 9.0880 (18) |
V (Å3) | 1903.8 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 4.30 |
Crystal size (mm) | 0.40 × 0.30 × 0.20 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.278, 0.480 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3687, 1877, 805 |
Rint | 0.054 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.067, 0.130, 0.96 |
No. of reflections | 1877 |
No. of parameters | 107 |
No. of restraints | 29 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.58, −0.49 |
Computer programs: CAD-4 Software (Enraf–Nonius, 1985), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2000).
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4A···O3 | 0.9300 | 2.4600 | 2.815 (7) | 103.00 |
C5—H5A···O2 | 0.9800 | 2.3400 | 2.693 (9) | 100.00 |
C7—H7C···O2i | 0.9600 | 2.3700 | 3.318 (11) | 170.00 |
Symmetry code: (i) −x+3/2, −y+3/2, z+1/2. |
The molecular structure of the title compound is shown in Fig. 1. The bond lengths and angles are within normal ranges (Allen et al., 1987).
The asymmetric unit contains one half-molecule; the full molecule being generated by a crystallographic twofold rotation axis. Weak intramolecular C—H···O hydrogen bonds may, in part, control the conformation of the molecule. In the crystal structure, molecules are connected into a two-dimensional network via weak intermolecular C—H···O hydrogen bonds. (Fig. 2).