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In the molecule of the title compound, C21H20Br2N2O4, the 4,10-dibromo-2,8-diethyl ester analogue of Tröger's base, the diazocine bridge imparts a twist such that the two aryl rings are offset with respect to one another. A twofold rotation axis passes through the bridgehead C atom. The asymmetric unit contains only one-half molecule and the dihedral angle between the two symmetry-related benzene rings is 98.24 (4)°.
Supporting information
CCDC reference: 615143
Key indicators
- Single-crystal X-ray study
- T = 150 K
- Mean (C-C) = 0.002 Å
- R factor = 0.025
- wR factor = 0.071
- Data-to-parameter ratio = 18.2
checkCIF/PLATON results
No syntax errors found
Alert level C
RINTA01_ALERT_3_C The value of Rint is greater than 0.10
Rint given 0.113
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 ......... 0.11
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
2 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
0 ALERT type 2 Indicator that the structure model may be wrong or deficient
2 ALERT type 3 Indicator that the structure quality may be low
0 ALERT type 4 Improvement, methodology, query or suggestion
0 ALERT type 5 Informative message, check
Data collection: SMART (Bruker, 1995); cell refinement: SAINT; data reduction: SAINT and XPREP (Bruker, 1995); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: Xtal3.6 (Hall et al., 1999), ORTEPII (Johnson, 1976); software used to prepare material for publication: WinGX (Farrugia, 1999).
4,10-Dibromo-2,8-di(ethoxycarbonyl)-6H,12
H-5,11-methanodibenzo[b,f][1,5]
diazocine
top
Crystal data top
C21H20Br2N2O4 | F(000) = 1048 |
Mr = 524.21 | Dx = 1.734 Mg m−3 |
Monoclinic, C2/c | Melting point: 463.29K K |
Hall symbol: -C 2yc | Mo Kα radiation, λ = 0.71073 Å |
a = 10.858 (2) Å | Cell parameters from 879 reflections |
b = 13.017 (3) Å | θ = 2.7–28.3° |
c = 14.325 (3) Å | µ = 4.07 mm−1 |
β = 97.333 (3)° | T = 150 K |
V = 2008.1 (7) Å3 | Prism, colorless |
Z = 4 | 0.51 × 0.36 × 0.31 mm |
Data collection top
Bruker SMART 1000 CCD diffractometer | 2423 independent reflections |
Radiation source: fine-focus sealed tube | 2141 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.113 |
ω scans | θmax = 28.3°, θmin = 2.5° |
Absorption correction: gaussian Gaussian (Coppens et al., 1965) (XPREP; Bruker, 1995) | h = −14→14 |
Tmin = 0.174, Tmax = 0.369 | k = −17→16 |
9748 measured reflections | l = −18→18 |
Refinement top
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)] = 0.025 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.071 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0217P)2 + 0.5345P] where P = (Fo2 + 2Fc2)/3 |
2423 reflections | (Δ/σ)max = 0.002 |
133 parameters | Δρmax = 0.55 e Å−3 |
0 restraints | Δρmin = −0.38 e Å−3 |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
Br1 | 0.867440 (15) | 0.308919 (16) | 0.865027 (12) | 0.02961 (9) | |
N1 | 0.60149 (12) | 0.38699 (11) | 0.79718 (9) | 0.0180 (3) | |
O1 | 0.89304 (11) | 0.07238 (10) | 0.55399 (9) | 0.0261 (3) | |
O2 | 0.69610 (11) | 0.06219 (10) | 0.48256 (9) | 0.0268 (3) | |
C1 | 0.64484 (15) | 0.31543 (12) | 0.73335 (11) | 0.0173 (3) | |
C2 | 0.76396 (14) | 0.27165 (13) | 0.75305 (11) | 0.0193 (3) | |
C3 | 0.80927 (15) | 0.20304 (13) | 0.69281 (12) | 0.0208 (3) | |
H3 | 0.8900 | 0.1747 | 0.7078 | 0.025* | |
C4 | 0.73608 (15) | 0.17555 (13) | 0.61005 (12) | 0.0192 (3) | |
C5 | 0.61804 (14) | 0.21878 (13) | 0.58791 (11) | 0.0190 (3) | |
H5 | 0.5684 | 0.2003 | 0.5309 | 0.023* | |
C6 | 0.57289 (14) | 0.28862 (13) | 0.64875 (11) | 0.0172 (3) | |
C7 | 0.44483 (14) | 0.33605 (14) | 0.62190 (11) | 0.0188 (3) | |
H7A | 0.4492 | 0.3870 | 0.5711 | 0.023* | |
H7B | 0.3857 | 0.2816 | 0.5974 | 0.023* | |
C8 | 0.5000 | 0.44991 (18) | 0.7500 | 0.0195 (4) | |
H8A | 0.5327 | 0.4947 | 0.7030 | 0.023* | |
C9 | 0.78512 (15) | 0.09852 (13) | 0.54705 (12) | 0.0212 (3) | |
C10 | 0.73143 (18) | −0.01655 (15) | 0.41959 (14) | 0.0293 (4) | |
H10A | 0.7481 | −0.0821 | 0.4539 | 0.035* | |
H10B | 0.8074 | 0.0042 | 0.3929 | 0.035* | |
C11 | 0.6256 (2) | −0.02880 (16) | 0.34310 (15) | 0.0359 (4) | |
H11A | 0.5512 | −0.0499 | 0.3704 | 0.054* | |
H11B | 0.6462 | −0.0813 | 0.2986 | 0.054* | |
H11C | 0.6097 | 0.0367 | 0.3101 | 0.054* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Br1 | 0.01841 (11) | 0.04414 (15) | 0.02453 (12) | −0.00156 (7) | −0.00397 (7) | −0.00324 (7) |
N1 | 0.0176 (6) | 0.0195 (7) | 0.0172 (6) | −0.0016 (5) | 0.0036 (5) | 0.0000 (5) |
O1 | 0.0229 (6) | 0.0260 (6) | 0.0306 (6) | 0.0085 (5) | 0.0078 (5) | 0.0039 (5) |
O2 | 0.0246 (6) | 0.0277 (7) | 0.0290 (6) | 0.0052 (5) | 0.0068 (5) | −0.0080 (6) |
C1 | 0.0167 (7) | 0.0170 (8) | 0.0184 (7) | −0.0016 (6) | 0.0031 (6) | 0.0019 (6) |
C2 | 0.0168 (7) | 0.0225 (8) | 0.0181 (7) | −0.0025 (6) | 0.0005 (6) | 0.0031 (6) |
C3 | 0.0154 (7) | 0.0220 (8) | 0.0252 (8) | 0.0030 (6) | 0.0029 (6) | 0.0056 (7) |
C4 | 0.0186 (8) | 0.0185 (7) | 0.0216 (7) | 0.0023 (6) | 0.0058 (6) | 0.0022 (6) |
C5 | 0.0188 (7) | 0.0209 (7) | 0.0172 (7) | 0.0013 (6) | 0.0026 (6) | 0.0012 (6) |
C6 | 0.0155 (7) | 0.0181 (7) | 0.0179 (7) | 0.0019 (6) | 0.0018 (6) | 0.0034 (6) |
C7 | 0.0168 (7) | 0.0227 (8) | 0.0168 (7) | 0.0042 (6) | 0.0021 (6) | −0.0012 (6) |
C8 | 0.0206 (10) | 0.0175 (10) | 0.0215 (10) | 0.000 | 0.0067 (9) | 0.000 |
C9 | 0.0243 (8) | 0.0181 (8) | 0.0227 (8) | 0.0032 (6) | 0.0089 (6) | 0.0050 (6) |
C10 | 0.0347 (9) | 0.0233 (9) | 0.0317 (9) | 0.0057 (8) | 0.0116 (8) | −0.0055 (8) |
C11 | 0.0460 (11) | 0.0276 (10) | 0.0340 (10) | 0.0055 (9) | 0.0050 (9) | −0.0089 (9) |
Geometric parameters (Å, º) top
Br1—C2 | 1.9001 (17) | C4—C9 | 1.492 (2) |
N1—C1 | 1.427 (2) | C5—C6 | 1.391 (2) |
N1—C8 | 1.467 (2) | C5—H5 | 0.9500 |
N1—C7i | 1.4782 (19) | C6—C7 | 1.525 (2) |
O1—C9 | 1.212 (2) | C7—H7A | 0.9900 |
O2—C9 | 1.335 (2) | C7—H7B | 0.9900 |
O2—C10 | 1.449 (2) | C8—H8A | 0.9901 |
C1—C6 | 1.400 (2) | C10—C11 | 1.492 (3) |
C1—C2 | 1.409 (2) | C10—H10A | 0.9900 |
C2—C3 | 1.376 (2) | C10—H10B | 0.9900 |
C3—C4 | 1.387 (3) | C11—H11A | 0.9800 |
C3—H3 | 0.9500 | C11—H11B | 0.9800 |
C4—C5 | 1.399 (2) | C11—H11C | 0.9800 |
| | | |
C1—N1—C8 | 111.05 (12) | N1i—C7—H7A | 109.2 |
C1—N1—C7i | 112.50 (13) | C6—C7—H7A | 109.2 |
C8—N1—C7i | 107.51 (10) | N1i—C7—H7B | 109.2 |
C9—O2—C10 | 117.08 (13) | C6—C7—H7B | 109.2 |
C6—C1—C2 | 117.99 (14) | H7A—C7—H7B | 107.9 |
C6—C1—N1 | 121.62 (14) | N1i—C8—N1 | 112.12 (19) |
C2—C1—N1 | 120.36 (15) | N1i—C8—H8A | 109.2 |
C3—C2—C1 | 121.98 (16) | N1—C8—H8A | 109.2 |
C3—C2—Br1 | 118.36 (13) | O1—C9—O2 | 124.35 (16) |
C1—C2—Br1 | 119.65 (12) | O1—C9—C4 | 123.72 (17) |
C2—C3—C4 | 119.45 (15) | O2—C9—C4 | 111.94 (13) |
C2—C3—H3 | 120.3 | O2—C10—C11 | 107.00 (14) |
C4—C3—H3 | 120.3 | O2—C10—H10A | 110.3 |
C3—C4—C5 | 119.90 (15) | C11—C10—H10A | 110.3 |
C3—C4—C9 | 118.71 (15) | O2—C10—H10B | 110.3 |
C5—C4—C9 | 121.38 (16) | C11—C10—H10B | 110.3 |
C6—C5—C4 | 120.46 (16) | H10A—C10—H10B | 108.6 |
C6—C5—H5 | 119.8 | C10—C11—H11A | 109.5 |
C4—C5—H5 | 119.8 | C10—C11—H11B | 109.5 |
C5—C6—C1 | 120.19 (15) | H11A—C11—H11B | 109.5 |
C5—C6—C7 | 119.30 (15) | C10—C11—H11C | 109.5 |
C1—C6—C7 | 120.50 (14) | H11A—C11—H11C | 109.5 |
N1i—C7—C6 | 111.99 (13) | H11B—C11—H11C | 109.5 |
| | | |
C8—N1—C1—C6 | −18.95 (19) | C2—C1—C6—C5 | 1.5 (2) |
C7i—N1—C1—C6 | 101.61 (17) | N1—C1—C6—C5 | 179.82 (14) |
C8—N1—C1—C2 | 159.28 (14) | C2—C1—C6—C7 | −178.03 (14) |
C7i—N1—C1—C2 | −80.16 (17) | N1—C1—C6—C7 | 0.3 (2) |
C6—C1—C2—C3 | −1.2 (2) | C5—C6—C7—N1i | 165.68 (14) |
N1—C1—C2—C3 | −179.46 (14) | C1—C6—C7—N1i | −14.7 (2) |
C6—C1—C2—Br1 | 177.98 (11) | C1—N1—C8—N1i | 54.24 (9) |
N1—C1—C2—Br1 | −0.32 (19) | C7i—N1—C8—N1i | −69.23 (10) |
C1—C2—C3—C4 | −0.1 (2) | C10—O2—C9—O1 | 2.5 (2) |
Br1—C2—C3—C4 | −179.24 (12) | C10—O2—C9—C4 | −177.49 (13) |
C2—C3—C4—C5 | 1.0 (2) | C3—C4—C9—O1 | −14.4 (2) |
C2—C3—C4—C9 | −178.08 (14) | C5—C4—C9—O1 | 166.63 (16) |
C3—C4—C5—C6 | −0.6 (2) | C3—C4—C9—O2 | 165.64 (15) |
C9—C4—C5—C6 | 178.44 (15) | C5—C4—C9—O2 | −13.4 (2) |
C4—C5—C6—C1 | −0.7 (2) | C9—O2—C10—C11 | −168.58 (15) |
C4—C5—C6—C7 | 178.86 (14) | | |
Symmetry code: (i) −x+1, y, −z+3/2. |
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