Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270103017955/sq1028sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103017955/sq1028Isup2.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103017955/sq1028IIsup3.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103017955/sq1028IIIsup4.hkl |
CCDC references: 224661; 224662; 224663
All of the title compounds were prepared from bis(3,5-dimethylphenyl) ditellurium, accessible via the Haller–Irgolic method (Haller & Irgolic, 1972). This compound was converted to bis(3,5-dimethyl-2- nitrophenyl) ditellurium by nitration and subsequent reduction (Nair, 2001). For the preparation of tribromo-(3,5-dimethyl-2-nitrophenyl- C,O)tellurium(IV), (I), bis(3,5-dimethyl-2-nitrophenyl) ditellurium (1.0 g, 1.8 mmol) was dissolved in carbon tetrachloride (30 ml). A 10% w/w solution of bromine in carbon tetrachloride was added slowly, and a gradual darkening to magenta was observed, followed by a sharp color change to yellow. Addition of bromine was discontinued and the product was crystallized by open-air evaporation. In contrast to non-coordinated aryltellurium trihalides, this compound was found to be insensitive to moisture (yield quantitative; m.p. 467–469 K). 1H NMR (CDCl3, p.p.m.): 2.58 (3H), 2.80 (3H), 7.51 (1H), 8.41 (1H). 13C NMR (CDCl3, p.p.m.): 22.5, 22.7, 129.5, 136.0, 137.5, 138.1, 140.8, 151.4. For the preparation of bromo-(3,5-dimethyl-2-nitrophenyl- C,O)tellurium(II), (II), bis(3,5-dimethyl-2-nitrophenyl) ditellurium (1.0 g, 1.8 mmol) was dissolved in carbon tetrachloride (30 ml). One third of the previously prepared ditellurium solution was converted to a solution of the tribromide by addition of bromine as above. Subsequently, the tribromide solution was combined with the remaining two parts of the bis(3,5-dimethyl- 2-nitrophenyl) ditellurium solution. Equilibration to the desired monobromide occurred rapidly. The crude product was collected by open-air evaporation of the solvent under the hood and recrystallized from cyclohexane (brown–red needles; yield 1.06 g, 82%; m.p. 380–381 K). 1H NMR (CDCl3, p.p.m.): 2.43 (3H), 2.79(3H), 7.19 (1H), 8.15 (1H). 13C NMR (CDCl3, p.p.m.): 21.9, 23.0, 131.8, 133.2, 134.1, 140.5, 144.3, 146.8. Well formed crystals were obtained by slow open-air evaporation of a solution in dichloromethane. For the preparation of bromo-(3,5-dimethyl-2-nitrosophenyl- C,O)tellurium(II), (III), a stirred solution of tribromo- (3,5-dimethyl-2-nitrophenyl-C,O)tellurium(IV) (0.2 g, 0.4 mmol) in acetone (20 ml) and 2-propanol (20 ml) was heated to reflux for 24 h. A color change from yellow to blue was noticed. The blue solid remaining after open-air evaporation under the hood was taken up in carbon tetrachloride and well formed blue crystals remaining after open-air evaporation were collected (yield 42 mg, 32%; m.p. 430–431 K). 1H NMR (CDCl3, p.p.m.): 2.36 (3H), 2.99 (3H), 7.26 (1H), 8.35 (1H). 13C NMR (CDCl3, p.p.m.): 18.9, 23.3, 132.4, 133.7, 138.1, 146.2, 149.1, 154.41.
H atoms were treated as riding in idealized positions, with C—H distances of 0.93–0.98 Å, depending on atom type and temperature. A torsional parameter was refined for each methyl group. Displacement parameters for H atoms were assigned as 1.2Ueq of the attached atom (1.5 for methyl groups). Friedel pairs were averaged for (I), since refinement of the Flack (1983) parameter led to a value of 0.509 (8), indicative of a racemic twin. The largest residual peak was 1.45 Å from atom Br3B for (I), 0.83 Å from the Te atom for (II) and 0.55 Å from atom Te1 for (III).
Data collection: COLLECT (Nonius, 2000) for (I), (III); CAD-4 EXPRESS (Enraf–Nonius, 1994) for (II). Cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997) for (I), (III); CAD-4 EXPRESS (Enraf–Nonius, 1994) for (II). Data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997) for (I), (III); maXus (Mackay et al., 1999) for (II). Program(s) used to solve structure: SIR97 (Altomare, et al., 1999) for (I); SIR97 (Altomare et al., 1999) for (II); SIR92 (Altomare et al., 1994) for (III). For all compounds, program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.
C8H8Br3NO2Te | F(000) = 1888 |
Mr = 517.48 | Dx = 2.717 Mg m−3 |
Orthorhombic, Pca21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2c -2ac | Cell parameters from 28416 reflections |
a = 7.371 (2) Å | θ = 2.5–32.0° |
b = 12.139 (5) Å | µ = 11.81 mm−1 |
c = 28.274 (11) Å | T = 120 K |
V = 2529.9 (16) Å3 | Prism, yellow |
Z = 8 | 0.20 × 0.17 × 0.15 mm |
KappaCCD (with Oxford Cryostream) diffractometer | 4303 independent reflections |
Radiation source: fine-focus sealed tube | 3800 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.032 |
ω scans with κ offsets | θmax = 32.0°, θmin = 3.2° |
Absorption correction: multi-scan HKL SCALEPACK (Otwinowski & Minor 1997) | h = −10→10 |
Tmin = 0.108, Tmax = 0.170 | k = −18→18 |
28416 measured reflections | l = −41→41 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.035 | H-atom parameters constrained |
wR(F2) = 0.087 | w = 1/[σ2(Fo2) + (0.0533P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.01 | (Δ/σ)max < 0.001 |
4303 reflections | Δρmax = 2.77 e Å−3 |
272 parameters | Δρmin = −2.44 e Å−3 |
1 restraint | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.00162 (17) |
C8H8Br3NO2Te | V = 2529.9 (16) Å3 |
Mr = 517.48 | Z = 8 |
Orthorhombic, Pca21 | Mo Kα radiation |
a = 7.371 (2) Å | µ = 11.81 mm−1 |
b = 12.139 (5) Å | T = 120 K |
c = 28.274 (11) Å | 0.20 × 0.17 × 0.15 mm |
KappaCCD (with Oxford Cryostream) diffractometer | 4303 independent reflections |
Absorption correction: multi-scan HKL SCALEPACK (Otwinowski & Minor 1997) | 3800 reflections with I > 2σ(I) |
Tmin = 0.108, Tmax = 0.170 | Rint = 0.032 |
28416 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 1 restraint |
wR(F2) = 0.087 | H-atom parameters constrained |
S = 1.01 | Δρmax = 2.77 e Å−3 |
4303 reflections | Δρmin = −2.44 e Å−3 |
272 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 | ||
Te1A | 0.92217 (6) | 0.37332 (3) | 0.106304 (17) | 0.01431 (10) | |
Br1A | 1.08917 (10) | 0.33061 (6) | 0.03087 (3) | 0.01852 (16) | |
Br2A | 1.21934 (12) | 0.34689 (7) | 0.15779 (3) | 0.02552 (18) | |
Br3A | 0.60060 (11) | 0.37082 (6) | 0.06261 (3) | 0.02202 (17) | |
O1A | 0.7642 (9) | 0.3653 (4) | 0.1824 (2) | 0.0239 (13) | |
O2A | 0.7028 (11) | 0.2544 (6) | 0.2393 (2) | 0.0361 (16) | |
N1A | 0.7495 (9) | 0.2714 (5) | 0.1988 (2) | 0.0189 (12) | |
C1A | 0.8665 (10) | 0.2048 (6) | 0.1228 (3) | 0.0149 (13) | |
C2A | 0.7893 (10) | 0.1789 (6) | 0.1672 (3) | 0.0153 (13) | |
C3A | 0.7537 (9) | 0.0698 (6) | 0.1804 (3) | 0.0141 (13) | |
C4A | 0.7900 (9) | −0.0111 (6) | 0.1475 (3) | 0.0151 (13) | |
H4A | 0.7652 | −0.0856 | 0.1555 | 0.018* | |
C5A | 0.8629 (9) | 0.0127 (6) | 0.1024 (3) | 0.0183 (14) | |
C6A | 0.8992 (10) | 0.1231 (6) | 0.0907 (3) | 0.0136 (13) | |
H6A | 0.9465 | 0.1409 | 0.0604 | 0.016* | |
C7A | 0.6730 (12) | 0.0337 (7) | 0.2277 (3) | 0.0247 (16) | |
H7A1 | 0.6179 | −0.0393 | 0.2243 | 0.037* | |
H7A2 | 0.5802 | 0.0867 | 0.2376 | 0.037* | |
H7A3 | 0.7691 | 0.0305 | 0.2516 | 0.037* | |
C8A | 0.8988 (11) | −0.0800 (6) | 0.0675 (3) | 0.0200 (15) | |
H8A1 | 0.8731 | −0.0544 | 0.0354 | 0.030* | |
H8A2 | 0.8204 | −0.1428 | 0.0750 | 0.030* | |
H8A3 | 1.0262 | −0.1027 | 0.0697 | 0.030* | |
Te1B | 0.63629 (6) | 0.12717 (3) | 0.394063 (17) | 0.01307 (10) | |
Br1B | 0.80492 (10) | 0.17320 (6) | 0.46789 (3) | 0.01840 (15) | |
Br2B | 0.93362 (11) | 0.15689 (7) | 0.34117 (3) | 0.02125 (16) | |
Br3B | 0.31764 (10) | 0.12576 (6) | 0.43809 (3) | 0.01941 (16) | |
O1B | 0.4641 (8) | 0.1285 (4) | 0.3221 (2) | 0.0201 (11) | |
O2B | 0.3274 (9) | 0.2367 (5) | 0.2728 (2) | 0.0305 (14) | |
N1B | 0.4201 (9) | 0.2243 (5) | 0.3081 (2) | 0.0172 (12) | |
C1B | 0.5705 (9) | 0.2938 (6) | 0.3783 (3) | 0.0138 (13) | |
C2B | 0.4786 (9) | 0.3188 (5) | 0.3364 (3) | 0.0152 (13) | |
C3B | 0.4379 (10) | 0.4269 (5) | 0.3219 (3) | 0.0151 (13) | |
C4B | 0.4878 (11) | 0.5085 (6) | 0.3544 (3) | 0.0203 (14) | |
H4B | 0.4612 | 0.5828 | 0.3465 | 0.024* | |
C5B | 0.5719 (9) | 0.4889 (6) | 0.3967 (3) | 0.0144 (12) | |
C6B | 0.6162 (10) | 0.3793 (6) | 0.4088 (3) | 0.0165 (14) | |
H6B | 0.6771 | 0.3640 | 0.4377 | 0.020* | |
C7B | 0.3583 (12) | 0.4584 (6) | 0.2752 (3) | 0.0229 (16) | |
H7B1 | 0.4302 | 0.4256 | 0.2497 | 0.034* | |
H7B2 | 0.3591 | 0.5388 | 0.2721 | 0.034* | |
H7B3 | 0.2332 | 0.4314 | 0.2733 | 0.034* | |
C8B | 0.6148 (11) | 0.5776 (6) | 0.4309 (3) | 0.0238 (17) | |
H8B1 | 0.7384 | 0.5674 | 0.4429 | 0.036* | |
H8B2 | 0.5287 | 0.5748 | 0.4572 | 0.036* | |
H8B3 | 0.6058 | 0.6492 | 0.4151 | 0.036* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Te1A | 0.0219 (2) | 0.00927 (17) | 0.0118 (2) | −0.00195 (14) | 0.00187 (18) | −0.00106 (17) |
Br1A | 0.0240 (4) | 0.0179 (3) | 0.0137 (4) | −0.0019 (3) | 0.0045 (3) | −0.0009 (3) |
Br2A | 0.0314 (4) | 0.0242 (4) | 0.0210 (4) | −0.0069 (3) | −0.0079 (4) | −0.0015 (3) |
Br3A | 0.0230 (4) | 0.0145 (3) | 0.0286 (5) | 0.0044 (3) | −0.0018 (3) | −0.0019 (3) |
O1A | 0.042 (3) | 0.012 (2) | 0.018 (3) | −0.002 (2) | 0.012 (3) | 0.001 (2) |
O2A | 0.069 (5) | 0.029 (3) | 0.010 (3) | 0.000 (3) | 0.014 (3) | −0.003 (2) |
N1A | 0.027 (3) | 0.018 (3) | 0.013 (3) | 0.000 (2) | 0.008 (2) | −0.002 (2) |
C1A | 0.024 (4) | 0.008 (3) | 0.013 (3) | 0.000 (2) | 0.000 (3) | −0.003 (2) |
C2A | 0.023 (3) | 0.015 (3) | 0.008 (3) | 0.001 (3) | 0.004 (2) | 0.000 (2) |
C3A | 0.013 (3) | 0.015 (3) | 0.014 (3) | −0.001 (2) | −0.001 (2) | −0.003 (2) |
C4A | 0.018 (3) | 0.012 (2) | 0.015 (4) | 0.001 (2) | −0.004 (2) | −0.004 (2) |
C5A | 0.015 (3) | 0.016 (3) | 0.023 (4) | 0.003 (2) | 0.000 (3) | 0.001 (3) |
C6A | 0.017 (3) | 0.016 (3) | 0.008 (3) | 0.002 (2) | 0.000 (2) | −0.005 (2) |
C7A | 0.032 (4) | 0.023 (4) | 0.020 (4) | −0.005 (3) | 0.001 (3) | 0.001 (3) |
C8A | 0.026 (4) | 0.018 (3) | 0.017 (4) | −0.002 (3) | 0.003 (3) | −0.007 (3) |
Te1B | 0.0184 (2) | 0.00841 (16) | 0.0123 (2) | 0.00115 (14) | −0.00128 (16) | −0.00081 (17) |
Br1B | 0.0245 (3) | 0.0166 (3) | 0.0141 (3) | 0.0024 (3) | −0.0054 (3) | 0.0005 (3) |
Br2B | 0.0222 (3) | 0.0218 (3) | 0.0197 (4) | 0.0015 (3) | 0.0032 (3) | −0.0034 (3) |
Br3B | 0.0217 (4) | 0.0146 (3) | 0.0220 (4) | −0.0044 (2) | 0.0038 (3) | −0.0014 (3) |
O1B | 0.027 (3) | 0.011 (2) | 0.022 (3) | −0.002 (2) | −0.004 (2) | −0.002 (2) |
O2B | 0.051 (4) | 0.024 (3) | 0.017 (3) | −0.003 (3) | −0.017 (3) | 0.002 (2) |
N1B | 0.025 (3) | 0.014 (3) | 0.013 (3) | 0.000 (2) | −0.002 (2) | −0.004 (2) |
C1B | 0.018 (3) | 0.010 (3) | 0.013 (3) | −0.003 (2) | 0.001 (2) | −0.002 (2) |
C2B | 0.014 (3) | 0.008 (2) | 0.023 (4) | −0.004 (2) | −0.002 (3) | −0.007 (3) |
C3B | 0.019 (3) | 0.011 (3) | 0.016 (3) | 0.003 (2) | 0.000 (2) | 0.007 (3) |
C4B | 0.022 (3) | 0.012 (3) | 0.026 (4) | 0.006 (3) | 0.001 (3) | 0.006 (3) |
C5B | 0.021 (3) | 0.011 (3) | 0.011 (3) | 0.002 (2) | 0.001 (3) | −0.003 (3) |
C6B | 0.019 (3) | 0.019 (3) | 0.011 (4) | −0.003 (3) | 0.000 (3) | 0.003 (3) |
C7B | 0.037 (4) | 0.017 (3) | 0.015 (4) | 0.009 (3) | −0.006 (3) | 0.002 (3) |
C8B | 0.025 (4) | 0.010 (3) | 0.036 (5) | −0.002 (3) | −0.001 (3) | −0.004 (3) |
Te1A—C1A | 2.138 (7) | Te1B—C1B | 2.127 (7) |
Te1A—O1A | 2.448 (6) | Te1B—O1B | 2.398 (6) |
Te1A—Br1A | 2.5165 (12) | Te1B—Br1B | 2.4929 (12) |
Te1A—Br2A | 2.6495 (11) | Te1B—Br3B | 2.6584 (10) |
Te1A—Br3A | 2.6731 (11) | Te1B—Br2B | 2.6776 (11) |
O1A—N1A | 1.236 (8) | O1B—N1B | 1.271 (8) |
O2A—N1A | 1.212 (8) | O2B—N1B | 1.218 (9) |
N1A—C2A | 1.466 (9) | N1B—C2B | 1.464 (9) |
C1A—C6A | 1.365 (9) | C1B—C6B | 1.390 (10) |
C1A—C2A | 1.414 (11) | C1B—C2B | 1.397 (11) |
C2A—C3A | 1.400 (10) | C2B—C3B | 1.408 (9) |
C3A—C4A | 1.379 (9) | C3B—C4B | 1.401 (12) |
C3A—C7A | 1.529 (11) | C3B—C7B | 1.493 (10) |
C4A—C5A | 1.415 (11) | C4B—C5B | 1.367 (11) |
C4A—H4A | 0.9500 | C4B—H4B | 0.9500 |
C5A—C6A | 1.406 (10) | C5B—C6B | 1.412 (10) |
C5A—C8A | 1.519 (11) | C5B—C8B | 1.482 (11) |
C6A—H6A | 0.9500 | C6B—H6B | 0.9500 |
C7A—H7A1 | 0.9800 | C7B—H7B1 | 0.9800 |
C7A—H7A2 | 0.9800 | C7B—H7B2 | 0.9800 |
C7A—H7A3 | 0.9800 | C7B—H7B3 | 0.9800 |
C8A—H8A1 | 0.9800 | C8B—H8B1 | 0.9800 |
C8A—H8A2 | 0.9800 | C8B—H8B2 | 0.9800 |
C8A—H8A3 | 0.9800 | C8B—H8B3 | 0.9800 |
C1A—Te1A—O1A | 71.3 (2) | C1B—Te1B—O1B | 72.2 (2) |
C1A—Te1A—Br1A | 94.7 (2) | C1B—Te1B—Br1B | 94.3 (2) |
O1A—Te1A—Br1A | 165.75 (12) | O1B—Te1B—Br1B | 166.60 (12) |
C1A—Te1A—Br2A | 85.6 (2) | C1B—Te1B—Br3B | 84.41 (19) |
O1A—Te1A—Br2A | 84.59 (17) | O1B—Te1B—Br3B | 85.96 (15) |
Br1A—Te1A—Br2A | 92.08 (4) | Br1B—Te1B—Br3B | 92.86 (4) |
C1A—Te1A—Br3A | 85.4 (2) | C1B—Te1B—Br2B | 86.66 (19) |
O1A—Te1A—Br3A | 89.08 (17) | O1B—Te1B—Br2B | 87.63 (15) |
Br1A—Te1A—Br3A | 92.27 (4) | Br1B—Te1B—Br2B | 91.68 (4) |
Br2A—Te1A—Br3A | 170.27 (3) | Br3B—Te1B—Br2B | 170.26 (3) |
N1A—O1A—Te1A | 114.1 (5) | N1B—O1B—Te1B | 114.0 (4) |
O2A—N1A—O1A | 122.5 (7) | O2B—N1B—O1B | 120.7 (6) |
O2A—N1A—C2A | 120.1 (7) | O2B—N1B—C2B | 121.2 (6) |
O1A—N1A—C2A | 117.4 (6) | O1B—N1B—C2B | 118.1 (6) |
C6A—C1A—C2A | 119.9 (7) | C6B—C1B—C2B | 118.7 (6) |
C6A—C1A—Te1A | 121.1 (6) | C6B—C1B—Te1B | 121.7 (5) |
C2A—C1A—Te1A | 118.9 (5) | C2B—C1B—Te1B | 119.6 (5) |
C3A—C2A—C1A | 121.5 (7) | C1B—C2B—C3B | 123.7 (6) |
C3A—C2A—N1A | 121.6 (6) | C1B—C2B—N1B | 115.9 (6) |
C1A—C2A—N1A | 116.9 (6) | C3B—C2B—N1B | 120.4 (7) |
C4A—C3A—C2A | 117.2 (7) | C4B—C3B—C2B | 114.3 (7) |
C4A—C3A—C7A | 117.4 (6) | C4B—C3B—C7B | 120.1 (6) |
C2A—C3A—C7A | 125.3 (6) | C2B—C3B—C7B | 125.5 (7) |
C3A—C4A—C5A | 122.4 (7) | C5B—C4B—C3B | 124.7 (7) |
C3A—C4A—H4A | 118.8 | C5B—C4B—H4B | 117.6 |
C5A—C4A—H4A | 118.8 | C3B—C4B—H4B | 117.6 |
C6A—C5A—C4A | 118.6 (7) | C4B—C5B—C6B | 118.8 (7) |
C6A—C5A—C8A | 121.4 (8) | C4B—C5B—C8B | 122.8 (7) |
C4A—C5A—C8A | 120.0 (7) | C6B—C5B—C8B | 118.5 (7) |
C1A—C6A—C5A | 120.2 (7) | C1B—C6B—C5B | 119.8 (7) |
C1A—C6A—H6A | 119.9 | C1B—C6B—H6B | 120.1 |
C5A—C6A—H6A | 119.9 | C5B—C6B—H6B | 120.1 |
C3A—C7A—H7A1 | 109.5 | C3B—C7B—H7B1 | 109.5 |
C3A—C7A—H7A2 | 109.5 | C3B—C7B—H7B2 | 109.5 |
H7A1—C7A—H7A2 | 109.5 | H7B1—C7B—H7B2 | 109.5 |
C3A—C7A—H7A3 | 109.5 | C3B—C7B—H7B3 | 109.5 |
H7A1—C7A—H7A3 | 109.5 | H7B1—C7B—H7B3 | 109.5 |
H7A2—C7A—H7A3 | 109.5 | H7B2—C7B—H7B3 | 109.5 |
C5A—C8A—H8A1 | 109.5 | C5B—C8B—H8B1 | 109.5 |
C5A—C8A—H8A2 | 109.5 | C5B—C8B—H8B2 | 109.5 |
H8A1—C8A—H8A2 | 109.5 | H8B1—C8B—H8B2 | 109.5 |
C5A—C8A—H8A3 | 109.5 | C5B—C8B—H8B3 | 109.5 |
H8A1—C8A—H8A3 | 109.5 | H8B1—C8B—H8B3 | 109.5 |
H8A2—C8A—H8A3 | 109.5 | H8B2—C8B—H8B3 | 109.5 |
C1A—Te1A—O1A—N1A | 10.3 (6) | C1B—Te1B—O1B—N1B | 1.8 (5) |
Br1A—Te1A—O1A—N1A | 0.2 (12) | Br1B—Te1B—O1B—N1B | 1.8 (11) |
Br2A—Te1A—O1A—N1A | −76.8 (6) | Br3B—Te1B—O1B—N1B | 87.2 (5) |
Br3A—Te1A—O1A—N1A | 95.8 (6) | Br2B—Te1B—O1B—N1B | −85.5 (5) |
Te1A—O1A—N1A—O2A | 167.4 (6) | Te1B—O1B—N1B—O2B | −177.6 (6) |
Te1A—O1A—N1A—C2A | −13.1 (9) | Te1B—O1B—N1B—C2B | 0.3 (8) |
O1A—Te1A—C1A—C6A | 172.7 (7) | O1B—Te1B—C1B—C6B | 176.2 (6) |
Br1A—Te1A—C1A—C6A | −9.8 (6) | Br1B—Te1B—C1B—C6B | −3.8 (6) |
Br2A—Te1A—C1A—C6A | −101.5 (6) | Br3B—Te1B—C1B—C6B | 88.7 (6) |
Br3A—Te1A—C1A—C6A | 82.1 (6) | Br2B—Te1B—C1B—C6B | −95.2 (6) |
O1A—Te1A—C1A—C2A | −5.3 (6) | O1B—Te1B—C1B—C2B | −3.7 (5) |
Br1A—Te1A—C1A—C2A | 172.2 (6) | Br1B—Te1B—C1B—C2B | 176.3 (5) |
Br2A—Te1A—C1A—C2A | 80.5 (6) | Br3B—Te1B—C1B—C2B | −91.2 (6) |
Br3A—Te1A—C1A—C2A | −95.9 (6) | Br2B—Te1B—C1B—C2B | 84.9 (6) |
C6A—C1A—C2A—C3A | 3.5 (11) | C6B—C1B—C2B—C3B | 3.6 (11) |
Te1A—C1A—C2A—C3A | −178.5 (5) | Te1B—C1B—C2B—C3B | −176.5 (6) |
C6A—C1A—C2A—N1A | −177.0 (7) | C6B—C1B—C2B—N1B | −174.7 (6) |
Te1A—C1A—C2A—N1A | 1.0 (9) | Te1B—C1B—C2B—N1B | 5.2 (9) |
O2A—N1A—C2A—C3A | 8.0 (11) | O2B—N1B—C2B—C1B | 174.5 (7) |
O1A—N1A—C2A—C3A | −171.5 (7) | O1B—N1B—C2B—C1B | −3.4 (10) |
O2A—N1A—C2A—C1A | −171.5 (8) | O2B—N1B—C2B—C3B | −3.9 (11) |
O1A—N1A—C2A—C1A | 9.0 (10) | O1B—N1B—C2B—C3B | 178.3 (7) |
C1A—C2A—C3A—C4A | −2.7 (11) | C1B—C2B—C3B—C4B | −3.7 (11) |
N1A—C2A—C3A—C4A | 177.8 (6) | N1B—C2B—C3B—C4B | 174.6 (7) |
C1A—C2A—C3A—C7A | 179.2 (7) | C1B—C2B—C3B—C7B | 173.0 (7) |
N1A—C2A—C3A—C7A | −0.3 (11) | N1B—C2B—C3B—C7B | −8.7 (12) |
C2A—C3A—C4A—C5A | 1.0 (10) | C2B—C3B—C4B—C5B | 1.1 (11) |
C7A—C3A—C4A—C5A | 179.3 (7) | C7B—C3B—C4B—C5B | −175.7 (7) |
C3A—C4A—C5A—C6A | −0.1 (10) | C3B—C4B—C5B—C6B | 1.3 (12) |
C3A—C4A—C5A—C8A | −179.6 (7) | C3B—C4B—C5B—C8B | −177.3 (7) |
C2A—C1A—C6A—C5A | −2.5 (11) | C2B—C1B—C6B—C5B | −0.9 (11) |
Te1A—C1A—C6A—C5A | 179.5 (5) | Te1B—C1B—C6B—C5B | 179.2 (5) |
C4A—C5A—C6A—C1A | 0.9 (11) | C4B—C5B—C6B—C1B | −1.4 (11) |
C8A—C5A—C6A—C1A | −179.7 (7) | C8B—C5B—C6B—C1B | 177.2 (7) |
C8H8BrNO2Te | F(000) = 1328 |
Mr = 357.66 | Dx = 2.278 Mg m−3 |
Monoclinic, I2/a | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -I 2ya | Cell parameters from 25 reflections |
a = 14.175 (4) Å | θ = 10.6–18.8° |
b = 9.582 (2) Å | µ = 6.65 mm−1 |
c = 15.433 (4) Å | T = 298 K |
β = 95.70 (2)° | Parallelepiped, red |
V = 2085.8 (9) Å3 | 0.35 × 0.22 × 0.20 mm |
Z = 8 |
Enraf–Nonius CAD-4 diffractometer | 1325 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.043 |
Graphite monochromator | θmax = 27.5°, θmin = 2.5° |
θ/2θ scans | h = −18→18 |
Absorption correction: ψ scan (North et al., 1968) | k = −11→12 |
Tmin = 0.202, Tmax = 0.266 | l = 0→20 |
7028 measured reflections | 3 standard reflections every 120 min |
2393 independent reflections | intensity decay: 0.8% |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.043 | H-atom parameters constrained |
wR(F2) = 0.104 | w = 1/[σ2(Fo2) + (0.0117P)2 + 3.15P] where P = (Fo2 + 2Fc2)/3 |
S = 1.10 | (Δ/σ)max = 0.003 |
2393 reflections | Δρmax = 0.95 e Å−3 |
121 parameters | Δρmin = −0.81 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.00020 (7) |
C8H8BrNO2Te | V = 2085.8 (9) Å3 |
Mr = 357.66 | Z = 8 |
Monoclinic, I2/a | Mo Kα radiation |
a = 14.175 (4) Å | µ = 6.65 mm−1 |
b = 9.582 (2) Å | T = 298 K |
c = 15.433 (4) Å | 0.35 × 0.22 × 0.20 mm |
β = 95.70 (2)° |
Enraf–Nonius CAD-4 diffractometer | 1325 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.043 |
Tmin = 0.202, Tmax = 0.266 | 3 standard reflections every 120 min |
7028 measured reflections | intensity decay: 0.8% |
2393 independent reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.104 | H-atom parameters constrained |
S = 1.10 | Δρmax = 0.95 e Å−3 |
2393 reflections | Δρmin = −0.81 e Å−3 |
121 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. The non-standard setting of I 2/a rather than the standard C 2/c was chosen since this choice produces cell constants that are closer to orthorhombic (beta is 95.70 (2) for I 2/a while beta would have been 134.84 for C 2/c). |
x | y | z | Uiso*/Ueq | ||
Te | 0.39572 (4) | 0.10060 (6) | 0.43265 (3) | 0.0635 (2) | |
Br | 0.51867 (6) | 0.28659 (12) | 0.48286 (7) | 0.0848 (4) | |
O1 | 0.2669 (5) | −0.0304 (5) | 0.3778 (4) | 0.0770 (17) | |
O2 | 0.1252 (5) | −0.0186 (6) | 0.3141 (5) | 0.091 (2) | |
N | 0.1955 (5) | 0.0396 (7) | 0.3467 (4) | 0.0611 (18) | |
C1 | 0.2896 (5) | 0.2427 (7) | 0.3870 (4) | 0.0414 (16) | |
C2 | 0.2035 (5) | 0.1898 (7) | 0.3507 (4) | 0.0435 (17) | |
C3 | 0.1270 (5) | 0.2737 (8) | 0.3202 (4) | 0.0484 (18) | |
C4 | 0.1428 (5) | 0.4158 (8) | 0.3250 (5) | 0.0530 (18) | |
H4 | 0.0940 | 0.4756 | 0.3044 | 0.064* | |
C5 | 0.2282 (5) | 0.4730 (7) | 0.3591 (5) | 0.0495 (18) | |
C6 | 0.3010 (5) | 0.3853 (7) | 0.3907 (4) | 0.0454 (16) | |
H6 | 0.3582 | 0.4229 | 0.4147 | 0.054* | |
C7 | 0.0302 (5) | 0.2237 (10) | 0.2822 (6) | 0.075 (3) | |
H7A | −0.0096 | 0.3028 | 0.2671 | 0.112* | |
H7B | 0.0023 | 0.1677 | 0.3245 | 0.112* | |
H7C | 0.0368 | 0.1690 | 0.2310 | 0.112* | |
C8 | 0.2426 (6) | 0.6307 (7) | 0.3620 (6) | 0.075 (3) | |
H8A | 0.2000 | 0.6719 | 0.3993 | 0.112* | |
H8B | 0.2302 | 0.6684 | 0.3043 | 0.112* | |
H8C | 0.3068 | 0.6513 | 0.3842 | 0.112* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Te | 0.0742 (4) | 0.0522 (3) | 0.0629 (3) | 0.0222 (3) | 0.0014 (3) | 0.0077 (3) |
Br | 0.0608 (5) | 0.1046 (8) | 0.0847 (7) | 0.0047 (5) | −0.0134 (5) | 0.0005 (6) |
O1 | 0.098 (4) | 0.038 (3) | 0.094 (5) | 0.005 (3) | 0.004 (4) | 0.003 (3) |
O2 | 0.098 (5) | 0.056 (4) | 0.117 (5) | −0.029 (4) | −0.001 (4) | −0.008 (4) |
N | 0.078 (5) | 0.038 (4) | 0.069 (5) | −0.018 (4) | 0.015 (4) | −0.001 (3) |
C1 | 0.045 (4) | 0.037 (4) | 0.041 (4) | 0.004 (3) | 0.000 (3) | −0.003 (3) |
C2 | 0.062 (5) | 0.030 (4) | 0.040 (4) | −0.005 (3) | 0.017 (3) | 0.001 (3) |
C3 | 0.049 (4) | 0.052 (5) | 0.044 (4) | −0.009 (4) | 0.006 (3) | 0.006 (4) |
C4 | 0.054 (4) | 0.049 (4) | 0.057 (4) | 0.004 (4) | 0.010 (3) | 0.007 (4) |
C5 | 0.055 (4) | 0.036 (4) | 0.059 (5) | 0.002 (3) | 0.010 (4) | 0.005 (3) |
C6 | 0.044 (4) | 0.041 (4) | 0.051 (4) | −0.002 (3) | 0.004 (3) | 0.002 (3) |
C7 | 0.057 (5) | 0.087 (7) | 0.078 (6) | −0.014 (5) | −0.004 (4) | 0.005 (5) |
C8 | 0.092 (6) | 0.036 (4) | 0.096 (7) | 0.001 (4) | 0.007 (5) | 0.000 (4) |
Te—C1 | 2.098 (6) | C4—C5 | 1.384 (9) |
Te—O1 | 2.307 (6) | C4—H4 | 0.9300 |
Te—Br | 2.5584 (12) | C5—C6 | 1.383 (9) |
O1—N | 1.268 (8) | C5—C8 | 1.525 (9) |
O2—N | 1.208 (8) | C6—H6 | 0.9300 |
N—C2 | 1.445 (9) | C7—H7A | 0.9600 |
C1—C6 | 1.376 (9) | C7—H7B | 0.9600 |
C1—C2 | 1.387 (9) | C7—H7C | 0.9600 |
C2—C3 | 1.393 (9) | C8—H8A | 0.9600 |
C3—C4 | 1.380 (9) | C8—H8B | 0.9600 |
C3—C7 | 1.515 (9) | C8—H8C | 0.9600 |
C1—Te—O1 | 73.4 (2) | C6—C5—C4 | 119.2 (6) |
C1—Te—Br | 95.38 (18) | C6—C5—C8 | 119.9 (7) |
O1—Te—Br | 168.80 (14) | C4—C5—C8 | 120.9 (7) |
N—O1—Te | 115.1 (4) | C1—C6—C5 | 120.5 (6) |
O2—N—O1 | 120.6 (7) | C1—C6—H6 | 119.7 |
O2—N—C2 | 122.4 (7) | C5—C6—H6 | 119.7 |
O1—N—C2 | 117.1 (6) | C3—C7—H7A | 109.5 |
C6—C1—C2 | 118.4 (6) | C3—C7—H7B | 109.5 |
C6—C1—Te | 123.5 (5) | H7A—C7—H7B | 109.5 |
C2—C1—Te | 118.1 (5) | C3—C7—H7C | 109.5 |
C1—C2—C3 | 123.3 (6) | H7A—C7—H7C | 109.5 |
C1—C2—N | 116.3 (7) | H7B—C7—H7C | 109.5 |
C3—C2—N | 120.4 (6) | C5—C8—H8A | 109.5 |
C4—C3—C2 | 115.8 (6) | C5—C8—H8B | 109.5 |
C4—C3—C7 | 117.9 (7) | H8A—C8—H8B | 109.5 |
C2—C3—C7 | 126.3 (7) | C5—C8—H8C | 109.5 |
C3—C4—C5 | 122.8 (7) | H8A—C8—H8C | 109.5 |
C3—C4—H4 | 118.6 | H8B—C8—H8C | 109.5 |
C5—C4—H4 | 118.6 | ||
C1—Te—O1—N | 0.3 (5) | O2—N—C2—C3 | 3.1 (12) |
Br—Te—O1—N | −3.1 (13) | O1—N—C2—C3 | −178.1 (6) |
Te—O1—N—O2 | 178.0 (6) | C1—C2—C3—C4 | 2.4 (10) |
Te—O1—N—C2 | −0.9 (9) | N—C2—C3—C4 | −178.4 (7) |
O1—Te—C1—C6 | −179.3 (7) | C1—C2—C3—C7 | −178.1 (7) |
Br—Te—C1—C6 | 0.0 (6) | N—C2—C3—C7 | 1.1 (11) |
O1—Te—C1—C2 | 0.3 (5) | C2—C3—C4—C5 | −1.0 (11) |
Br—Te—C1—C2 | 179.6 (5) | C7—C3—C4—C5 | 179.4 (7) |
C6—C1—C2—C3 | −2.0 (11) | C3—C4—C5—C6 | −0.7 (11) |
Te—C1—C2—C3 | 178.4 (5) | C3—C4—C5—C8 | 179.2 (7) |
C6—C1—C2—N | 178.8 (6) | C2—C1—C6—C5 | 0.1 (11) |
Te—C1—C2—N | −0.8 (9) | Te—C1—C6—C5 | 179.7 (5) |
O2—N—C2—C1 | −177.7 (7) | C4—C5—C6—C1 | 1.1 (11) |
O1—N—C2—C1 | 1.1 (10) | C8—C5—C6—C1 | −178.8 (7) |
C8H8BrNOTe | F(000) = 1264 |
Mr = 341.66 | Dx = 2.376 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 4719 reflections |
a = 11.291 (6) Å | θ = 2.5–32.0° |
b = 12.788 (5) Å | µ = 7.25 mm−1 |
c = 14.332 (7) Å | T = 120 K |
β = 112.62 (3)° | Prism, dark red |
V = 1910.2 (16) Å3 | 0.20 × 0.15 × 0.15 mm |
Z = 8 |
KappaCCD (with Oxford Cryostream) diffractometer | 3272 independent reflections |
Radiation source: fine-focus sealed tube | 2511 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.032 |
ω scans with κ offsets | θmax = 32.0°, θmin = 3.1° |
Absorption correction: multi-scan HKL SCALEPACK (Otwinowski & Minor 1997) | h = −16→16 |
Tmin = 0.268, Tmax = 0.337 | k = −18→13 |
4540 measured reflections | l = −20→21 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.040 | H-atom parameters constrained |
wR(F2) = 0.123 | w = 1/[σ2(Fo2) + (0.0702P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max = 0.001 |
3272 reflections | Δρmax = 1.30 e Å−3 |
112 parameters | Δρmin = −2.03 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.00086 (19) |
C8H8BrNOTe | V = 1910.2 (16) Å3 |
Mr = 341.66 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 11.291 (6) Å | µ = 7.25 mm−1 |
b = 12.788 (5) Å | T = 120 K |
c = 14.332 (7) Å | 0.20 × 0.15 × 0.15 mm |
β = 112.62 (3)° |
KappaCCD (with Oxford Cryostream) diffractometer | 3272 independent reflections |
Absorption correction: multi-scan HKL SCALEPACK (Otwinowski & Minor 1997) | 2511 reflections with I > 2σ(I) |
Tmin = 0.268, Tmax = 0.337 | Rint = 0.032 |
4540 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.123 | H-atom parameters constrained |
S = 1.09 | Δρmax = 1.30 e Å−3 |
3272 reflections | Δρmin = −2.03 e Å−3 |
112 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 | ||
Te1 | 0.43509 (3) | 0.396095 (19) | 0.08624 (2) | 0.02207 (11) | |
Br1 | 0.60033 (5) | 0.32059 (4) | 0.01402 (4) | 0.03484 (15) | |
O1 | 0.2933 (3) | 0.4285 (3) | 0.1498 (2) | 0.0282 (7) | |
N1 | 0.2464 (4) | 0.3474 (3) | 0.1805 (3) | 0.0259 (7) | |
C1 | 0.3875 (3) | 0.2510 (3) | 0.1194 (3) | 0.0177 (7) | |
C2 | 0.2956 (3) | 0.2553 (3) | 0.1670 (3) | 0.0200 (7) | |
C3 | 0.2499 (4) | 0.1612 (3) | 0.1974 (3) | 0.0210 (8) | |
C4 | 0.2961 (4) | 0.0690 (3) | 0.1783 (3) | 0.0224 (8) | |
H4 | 0.2677 | 0.0059 | 0.1979 | 0.027* | |
C5 | 0.3845 (4) | 0.0628 (3) | 0.1303 (3) | 0.0207 (8) | |
C6 | 0.4303 (4) | 0.1535 (3) | 0.1021 (3) | 0.0197 (7) | |
H6 | 0.4907 | 0.1490 | 0.0709 | 0.024* | |
C7 | 0.1569 (4) | 0.1706 (3) | 0.2496 (4) | 0.0268 (9) | |
H7A | 0.0962 | 0.1121 | 0.2293 | 0.040* | |
H7B | 0.1098 | 0.2367 | 0.2302 | 0.040* | |
H7C | 0.2042 | 0.1691 | 0.3230 | 0.040* | |
C8 | 0.4270 (4) | −0.0413 (3) | 0.1063 (4) | 0.0265 (9) | |
H8A | 0.3617 | −0.0688 | 0.0440 | 0.040* | |
H8B | 0.4390 | −0.0900 | 0.1620 | 0.040* | |
H8C | 0.5083 | −0.0330 | 0.0973 | 0.040* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Te1 | 0.02458 (16) | 0.01743 (16) | 0.02281 (17) | −0.00170 (9) | 0.00758 (11) | 0.00132 (10) |
Br1 | 0.0335 (3) | 0.0348 (3) | 0.0402 (3) | −0.00372 (19) | 0.0186 (2) | 0.0024 (2) |
O1 | 0.0324 (17) | 0.0212 (14) | 0.0331 (17) | 0.0001 (12) | 0.0150 (14) | −0.0049 (13) |
N1 | 0.0272 (18) | 0.0220 (17) | 0.0275 (18) | 0.0046 (14) | 0.0095 (15) | 0.0019 (15) |
C1 | 0.0163 (16) | 0.0181 (17) | 0.0159 (16) | −0.0010 (13) | 0.0029 (13) | 0.0013 (14) |
C2 | 0.0156 (17) | 0.0237 (19) | 0.0199 (17) | 0.0012 (14) | 0.0061 (14) | −0.0002 (15) |
C3 | 0.0180 (17) | 0.027 (2) | 0.0180 (17) | −0.0001 (14) | 0.0064 (14) | −0.0002 (15) |
C4 | 0.0220 (19) | 0.0192 (18) | 0.0243 (19) | −0.0013 (15) | 0.0071 (16) | 0.0019 (16) |
C5 | 0.0189 (17) | 0.0193 (18) | 0.0228 (19) | 0.0028 (14) | 0.0067 (15) | −0.0014 (16) |
C6 | 0.0159 (17) | 0.0222 (19) | 0.0225 (18) | 0.0009 (13) | 0.0091 (15) | −0.0017 (15) |
C7 | 0.024 (2) | 0.029 (2) | 0.033 (2) | 0.0006 (16) | 0.0175 (18) | 0.0022 (18) |
C8 | 0.025 (2) | 0.0192 (19) | 0.036 (2) | 0.0004 (15) | 0.0136 (18) | −0.0038 (17) |
Te1—C1 | 2.038 (4) | C4—H4 | 0.9500 |
Te1—O1 | 2.165 (3) | C5—C6 | 1.392 (6) |
Te1—Br1 | 2.6401 (16) | C5—C8 | 1.499 (6) |
O1—N1 | 1.315 (5) | C6—H6 | 0.9500 |
N1—C2 | 1.348 (5) | C7—H7A | 0.9800 |
C1—C6 | 1.394 (6) | C7—H7B | 0.9800 |
C1—C2 | 1.445 (5) | C7—H7C | 0.9800 |
C2—C3 | 1.441 (6) | C8—H8A | 0.9800 |
C3—C4 | 1.360 (6) | C8—H8B | 0.9800 |
C3—C7 | 1.510 (6) | C8—H8C | 0.9800 |
C4—C5 | 1.415 (6) | ||
C1—Te1—O1 | 76.81 (14) | C6—C5—C8 | 119.1 (4) |
C1—Te1—Br1 | 92.76 (11) | C4—C5—C8 | 120.6 (4) |
O1—Te1—Br1 | 169.57 (9) | C5—C6—C1 | 120.0 (4) |
N1—O1—Te1 | 116.6 (3) | C5—C6—H6 | 120.0 |
O1—N1—C2 | 113.5 (4) | C1—C6—H6 | 120.0 |
C6—C1—C2 | 118.6 (3) | C3—C7—H7A | 109.5 |
C6—C1—Te1 | 129.2 (3) | C3—C7—H7B | 109.5 |
C2—C1—Te1 | 112.2 (3) | H7A—C7—H7B | 109.5 |
N1—C2—C3 | 118.0 (4) | C3—C7—H7C | 109.5 |
N1—C2—C1 | 120.8 (4) | H7A—C7—H7C | 109.5 |
C3—C2—C1 | 121.1 (3) | H7B—C7—H7C | 109.5 |
C4—C3—C2 | 117.0 (4) | C5—C8—H8A | 109.5 |
C4—C3—C7 | 124.2 (4) | C5—C8—H8B | 109.5 |
C2—C3—C7 | 118.8 (4) | H8A—C8—H8B | 109.5 |
C3—C4—C5 | 122.9 (4) | C5—C8—H8C | 109.5 |
C3—C4—H4 | 118.6 | H8A—C8—H8C | 109.5 |
C5—C4—H4 | 118.6 | H8B—C8—H8C | 109.5 |
C6—C5—C4 | 120.3 (4) | ||
C1—Te1—O1—N1 | 1.3 (3) | N1—C2—C3—C4 | 176.8 (4) |
Br1—Te1—O1—N1 | 2.4 (7) | C1—C2—C3—C4 | −0.7 (6) |
Te1—O1—N1—C2 | 0.0 (4) | N1—C2—C3—C7 | −4.3 (6) |
O1—Te1—C1—C6 | 177.5 (4) | C1—C2—C3—C7 | 178.2 (4) |
Br1—Te1—C1—C6 | −2.3 (3) | C2—C3—C4—C5 | −0.3 (6) |
O1—Te1—C1—C2 | −2.1 (2) | C7—C3—C4—C5 | −179.2 (4) |
Br1—Te1—C1—C2 | 178.1 (2) | C3—C4—C5—C6 | 1.2 (6) |
O1—N1—C2—C3 | −179.6 (3) | C3—C4—C5—C8 | −176.8 (4) |
O1—N1—C2—C1 | −2.1 (5) | C4—C5—C6—C1 | −1.1 (6) |
C6—C1—C2—N1 | −176.5 (3) | C8—C5—C6—C1 | 177.0 (4) |
Te1—C1—C2—N1 | 3.1 (5) | C2—C1—C6—C5 | 0.0 (5) |
C6—C1—C2—C3 | 0.9 (5) | Te1—C1—C6—C5 | −179.6 (3) |
Te1—C1—C2—C3 | −179.5 (3) |
Experimental details
(I) | (II) | (III) | |
Crystal data | |||
Chemical formula | C8H8Br3NO2Te | C8H8BrNO2Te | C8H8BrNOTe |
Mr | 517.48 | 357.66 | 341.66 |
Crystal system, space group | Orthorhombic, Pca21 | Monoclinic, I2/a | Monoclinic, C2/c |
Temperature (K) | 120 | 298 | 120 |
a, b, c (Å) | 7.371 (2), 12.139 (5), 28.274 (11) | 14.175 (4), 9.582 (2), 15.433 (4) | 11.291 (6), 12.788 (5), 14.332 (7) |
α, β, γ (°) | 90, 90, 90 | 90, 95.70 (2), 90 | 90, 112.62 (3), 90 |
V (Å3) | 2529.9 (16) | 2085.8 (9) | 1910.2 (16) |
Z | 8 | 8 | 8 |
Radiation type | Mo Kα | Mo Kα | Mo Kα |
µ (mm−1) | 11.81 | 6.65 | 7.25 |
Crystal size (mm) | 0.20 × 0.17 × 0.15 | 0.35 × 0.22 × 0.20 | 0.20 × 0.15 × 0.15 |
Data collection | |||
Diffractometer | KappaCCD (with Oxford Cryostream) diffractometer | Enraf–Nonius CAD-4 diffractometer | KappaCCD (with Oxford Cryostream) diffractometer |
Absorption correction | Multi-scan HKL SCALEPACK (Otwinowski & Minor 1997) | ψ scan (North et al., 1968) | Multi-scan HKL SCALEPACK (Otwinowski & Minor 1997) |
Tmin, Tmax | 0.108, 0.170 | 0.202, 0.266 | 0.268, 0.337 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 28416, 4303, 3800 | 7028, 2393, 1325 | 4540, 3272, 2511 |
Rint | 0.032 | 0.043 | 0.032 |
(sin θ/λ)max (Å−1) | 0.746 | 0.650 | 0.746 |
Refinement | |||
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.087, 1.01 | 0.043, 0.104, 1.10 | 0.040, 0.123, 1.09 |
No. of reflections | 4303 | 2393 | 3272 |
No. of parameters | 272 | 121 | 112 |
No. of restraints | 1 | 0 | 0 |
H-atom treatment | H-atom parameters constrained | H-atom parameters constrained | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 2.77, −2.44 | 0.95, −0.81 | 1.30, −2.03 |
Computer programs: COLLECT (Nonius, 2000), CAD-4 EXPRESS (Enraf–Nonius, 1994), DENZO and SCALEPACK (Otwinowski & Minor, 1997), maXus (Mackay et al., 1999), SIR97 (Altomare, et al., 1999), SIR97 (Altomare et al., 1999), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997), SHELXL97.
Te1A—C1A | 2.138 (7) | Te1B—C1B | 2.127 (7) |
Te1A—O1A | 2.448 (6) | Te1B—O1B | 2.398 (6) |
Te1A—Br1A | 2.5165 (12) | Te1B—Br1B | 2.4929 (12) |
Te1A—Br2A | 2.6495 (11) | Te1B—Br3B | 2.6584 (10) |
Te1A—Br3A | 2.6731 (11) | Te1B—Br2B | 2.6776 (11) |
O1A—N1A | 1.236 (8) | O1B—N1B | 1.271 (8) |
O2A—N1A | 1.212 (8) | O2B—N1B | 1.218 (9) |
N1A—C2A | 1.466 (9) | N1B—C2B | 1.464 (9) |
C1A—Te1A—O1A | 71.3 (2) | C1B—Te1B—O1B | 72.2 (2) |
C1A—Te1A—Br1A | 94.7 (2) | C1B—Te1B—Br1B | 94.3 (2) |
O1A—Te1A—Br1A | 165.75 (12) | O1B—Te1B—Br1B | 166.60 (12) |
C1A—Te1A—Br2A | 85.6 (2) | C1B—Te1B—Br3B | 84.41 (19) |
O1A—Te1A—Br2A | 84.59 (17) | O1B—Te1B—Br3B | 85.96 (15) |
Br1A—Te1A—Br2A | 92.08 (4) | Br1B—Te1B—Br3B | 92.86 (4) |
C1A—Te1A—Br3A | 85.4 (2) | C1B—Te1B—Br2B | 86.66 (19) |
O1A—Te1A—Br3A | 89.08 (17) | O1B—Te1B—Br2B | 87.63 (15) |
Br1A—Te1A—Br3A | 92.27 (4) | Br1B—Te1B—Br2B | 91.68 (4) |
Br2A—Te1A—Br3A | 170.27 (3) | Br3B—Te1B—Br2B | 170.26 (3) |
N1A—O1A—Te1A | 114.1 (5) | N1B—O1B—Te1B | 114.0 (4) |
C6A—C1A—Te1A | 121.1 (6) | C6B—C1B—Te1B | 121.7 (5) |
C2A—C1A—Te1A | 118.9 (5) | C2B—C1B—Te1B | 119.6 (5) |
Te—C1 | 2.098 (6) | O1—N | 1.268 (8) |
Te—O1 | 2.307 (6) | O2—N | 1.208 (8) |
Te—Br | 2.5584 (12) | N—C2 | 1.445 (9) |
C1—Te—O1 | 73.4 (2) | O1—N—C2 | 117.1 (6) |
C1—Te—Br | 95.38 (18) | C6—C1—C2 | 118.4 (6) |
O1—Te—Br | 168.80 (14) | C6—C1—Te | 123.5 (5) |
N—O1—Te | 115.1 (4) | C2—C1—Te | 118.1 (5) |
O2—N—O1 | 120.6 (7) | C1—C2—N | 116.3 (7) |
O2—N—C2 | 122.4 (7) | C3—C2—N | 120.4 (6) |
Te1—C1 | 2.038 (4) | O1—N1 | 1.315 (5) |
Te1—O1 | 2.165 (3) | N1—C2 | 1.348 (5) |
Te1—Br1 | 2.6401 (16) | ||
C1—Te1—O1 | 76.81 (14) | C6—C1—C2 | 118.6 (3) |
C1—Te1—Br1 | 92.76 (11) | C6—C1—Te1 | 129.2 (3) |
O1—Te1—Br1 | 169.57 (9) | C2—C1—Te1 | 112.2 (3) |
N1—O1—Te1 | 116.6 (3) | N1—C2—C3 | 118.0 (4) |
O1—N1—C2 | 113.5 (4) | N1—C2—C1 | 120.8 (4) |
Intramolecularly coordinated organotellurium compounds commonly exhibit properties that are significantly different from those of their non-coordinated counterparts. Moieties through which a Lewis basic atom intramolecularly coordinates to tellurium include azo, imino, carbonyl and amino functionalities (Detty & O'Regan, 1994). This coordination can stabilize otherwise unstable low-valent organotellurium halides and pseudohalides (Cobbledick et al., 1979; Detty et al., 1989; Sadekov et al., 1990; Menon et al., 1996) as well as telluronium cations (Fujihara et al., 1995). Intramolecular coordination by nitroso and nitro moieties has not been documented in much detail because of limited access to these classes of organotellurium compounds. Thus, the only published procedure for the preparation of an ortho nitro- substituted diphenyl ditellurium (Wiriyachitra et al., 1979) was found to be challenging. The few reported examples for –NO and –NO2 coordination include dioxatellurapentalenes (Perrier & Vialle, 1971) and 1-nitroso-2-naphthyltellurium monohalides found in the patent literature (Przyklek-Elling et al., 1987; Gunther & Lok, 1986). It appears highly probable that bromo-(2-nitrophenyl)tellurium(II) and tribromo-(2-nitrophenyl)tellurium(IV) (Wiriyachitra et al., 1979) also feature strong intramolecular Te—O coordination, but no structural information has been made available for these compounds to date. Compounds carrying ortho nitro, nitroso and amino functionalities are of interest as potential precursors to compounds featuring coordinatively stabilized telluronium cations and as intermediates to organotellurium heterocycles (Junk & Irgolic, 1988).
Recent advances in the synthesis of substituted diaryl ditelluriums by selective ortho nitration, as well as from boronic acid precursors (Clark et al., 2002), have provided easier access to compounds like bis(3,5-dimethyl-2-nitrophenyl) ditellurium, which is employed in this study. Bis(3,5-dimethyl-2-nitrophenyl) ditellurium was prepared by nitration of bis(3,5-dimethylphenyl) ditellurium to 3,5-dimethyl-2-nitrobenzenetellurinic acid nitrate, followed by reduction. [Experimental Scheme inserted here rxn.eps] Treatment of bis(3,5-dimethyl-2-nitrophenyl) ditellurium with stoichiometric amounts of bromine produced tribromo-(3,5-dimethyl-2-nitrophenyl-C,O)tellurium(IV), (I), and bromo-(3,5-dimethyl-2-nitrosophenyl-C,O)tellurium(II), (III), which may be described as heterocyclic (a substituted benzoxatellurazole).
Two molecules of tribromo-(3,5-dimethyl-2-nitrophenyl- C,O)tellurium(IV), (I), of nearly identical geometry are contained in the asymmetric unit. There appears to be a non-crystallographic center of symmetry between the two independent molecules (at about x = 0.105, y = 0.248 and z = 1/2). Similar centers appear in more than 65% of Pca21 structures where Z > 4 (Marsh et al. 1998), and often result in unusual correlations between corresponding atoms in the two molecules. Since the average values of equivalent bond distances are apparently unaffected by this pseudosymmetry (Marsh et al. 1998), we discuss the average case. The geometry about the Te atom is square-pyramidal, with the basal plane defined by three Br atoms and the O atom. The C atom is in the axial position, and a stereochemical lone pair is located trans to this C atom. The Te atom sits `below' the basal plane, which is consistent with the principles of VSEPR theory. The Te—Br distance for Br trans to oxygen is significantly shorter than the other distances [2.5047 (12) Å versus 2.6540 (11) and 2.6754 (11) Å]. The Te1—C1 bond distance [2.132 (7) Å] is in good agreement with those reported for non-coordinated aryl–Te bonds, e.g. 2.140 (8) Å in catena-(µ-2-bromo)-dibromo-phenyl-tellurium(IV) (Alcock & Harrison, 1982a). The O1—Te1—C1 angle is constrained to 71.8 (2)° by the five-membered ring. These structural features are similar to those reported for trichloro-(2-phenylazophenyl-C,N')tellurium(IV), in which there is coordination of tellurium by the N atom of the azo group (Ahmed et al., 1985a). There is a short intermolecular contact in (I) between atoms O2A and N1B, which is reminiscent of the perpendicular motif found for carbonyl–carbonyl interactions (Allen et al. 1998).
The geometries of (II) and (III), are `T-shaped' about the Te atom, with the O—Te—Br angles distinctly non-linear [168.80 (14) and 169.58 (1)°, respectively] and the bromide ion displaced towards the phenyl ring, which geometry is again consistent with VSEPR theory and the presence of two stereochemical lone pairs of electrons on the TeII centers. The N—O distance in (III) [1.315 (4) Å] is significantly longer than the analogous distance in (II) [1.268 (8) Å], which is significantly longer than the other (non-coordinated) N—O distance of 1.208 (8) Å. The Te—C distance of 2.098 (6) Å in (II) is the same as that found in bromo-(2-phenylazophenyl- C,N)tellurium(II) [2.092 (8) Å; Majeed et al., 1997], while the Te—C distance is shortened to 2.038 (4) Å in (III).
The Te—O bond distances of 2.307 (6) Å in (II) and 2.1648 (7) Å in (III) are shorter than the Te—O distance of 2.423 (6) Å for (I) and are compare to Te—O distances observed for amides [e.g. 2.237 (8) Å for bromo-(2-amidophenyl- C,O)tellurium(II); Dupont et al., 1979], for carboxylates [e.g. 2.167 (4) Å for acetato-(2-phenylazophenyl- C,N')tellurium(II); Ahmed et al., 1985b] and for nitrate [e.g. 2.171 (3) Å for diphenyltellurium(IV) dinitrate; Alcock & Harrison, 1982b].
The relative ease with which (I) was reduced to (III) is indicative of the high stability of ortho nitroso-stabilized aryl tellurium subhalides. In practice, exposure of the tellurium(IV) compound to a variety of ketones and alcohols resulted in gradual color changes indicative of reduction.