endo,endo,endo-9,9,10,11,12-Penta­bromo­tri­cyclo­[6.2.2.0^2,7]­dodeca-2(7),3,5-triene

The title compound, C₁₂H₉Br₅, involves two non-planar six-membered carbon rings constituting a bicyclic system. One of these non-planar carbon rings shares two C atoms with a benzene ring and has three Br substituents, while the second non-planar carbon ring has two Br substituents. The repulsive interaction between the neighbouring Br atoms is evidenced by the enlargement of the respective Br-C-Br and Br-C-C angles.

Key indicators

• Single-crystal X-ray study
• T = 301 K
• Mean [sigma](C-C) = 0.017 Å
• R factor = 0.065
• wR factor = 0.149
• Data-to-parameter ratio = 17.8

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_213  Alert C Atom C9      has ADP max/min Ratio ...........       3.20 oblate


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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Computing details

Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1993); cell refinement: SHELXL97 (Sheldrick, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97; molecular graphics: PLATON (Spek, 2000); software used to prepare material for publication: SHELXL97.

(I)

Crystal data

C12H9Br5	F(000) = 1024
Mr = 552.74	Dx = 2.553 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 25 reflections
a = 9.8779 (12) Å	θ = 2.4–26.0°
b = 13.0945 (13) Å	µ = 13.95 mm^−1
c = 11.5305 (11) Å	T = 301 K
β = 105.354 (7)°	Prism, colourless
V = 1438.2 (3) Å^3	0.25 × 0.20 × 0.15 mm
Z = 4

Data collection

CAD-4 EXPRESS (Enraf-Nonius, 1993) diffractometer	Rint = 0.071
ω/2θ scans	θmax = 26.0°
Absorption correction: ψ scan (Fair, 1990)	h = −12→11
Tmin = 0.047, Tmax = 0.123	k = 0→16
2897 measured reflections	l = 0→14
2761 independent reflections	3 standard reflections every 120 min
1585 reflections with I > 2σ(I)	intensity decay: 1.2%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.065	H-atom parameters constrained
wR(F^2) = 0.149	w = 1/[σ^2(Fo^2) + (0.1154P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.93	(Δ/σ)max = 0.0001
2761 reflections	Δρmax = 2.25 e Å^−3
155 parameters	Δρmin = −1.07 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0020 (6)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.82468 (13)	0.37031 (11)	0.29094 (12)	0.0452 (4)
Br2	0.61056 (15)	0.52185 (10)	0.38707 (12)	0.0432 (4)
Br3	0.18518 (14)	0.22819 (11)	0.24437 (13)	0.0431 (4)
Br4	0.40049 (19)	0.07202 (12)	0.16462 (18)	0.0652 (6)
Br5	0.39351 (16)	0.20976 (11)	0.49645 (11)	0.0489 (5)
C1	0.6717 (11)	0.3048 (9)	0.3400 (9)	0.027 (3)
C2	0.5738 (12)	0.3757 (8)	0.3880 (10)	0.029 (3)
C3	0.4221 (11)	0.3581 (8)	0.3161 (9)	0.024 (3)
C4	0.3825 (11)	0.2454 (9)	0.3283 (10)	0.025 (3)
C5	0.4860 (13)	0.1734 (9)	0.2848 (12)	0.037 (3)
C6	0.5827 (12)	0.2435 (9)	0.2330 (10)	0.030 (3)
C7	0.4974 (12)	0.3130 (8)	0.1391 (9)	0.025 (3)
C8	0.4975 (17)	0.3179 (11)	0.0205 (11)	0.045 (4)
C9	0.4088 (17)	0.3861 (12)	−0.0507 (12)	0.051 (4)
C10	0.3239 (18)	0.4479 (10)	−0.0090 (13)	0.054 (4)
C11	0.3208 (15)	0.4399 (10)	0.1111 (12)	0.042 (3)
C12	0.4068 (11)	0.3739 (8)	0.1834 (10)	0.022 (2)
H1	0.7134	0.2561	0.4040	0.032*
H2	0.5812	0.3558	0.4714	0.034*
H3	0.3586	0.4036	0.3442	0.029*
H5	0.5444	0.1377	0.3551	0.044*
H6	0.6441	0.2015	0.1982	0.036*
H8	0.5558	0.2762	−0.0104	0.054*
H9	0.4070	0.3900	−0.1316	0.062*
H10	0.2677	0.4955	−0.0595	0.065*
H11	0.2597	0.4801	0.1405	0.051*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0272 (7)	0.0617 (9)	0.0464 (9)	0.0106 (7)	0.0092 (6)	−0.0099 (7)
Br2	0.0568 (9)	0.0318 (7)	0.0389 (8)	−0.0013 (6)	0.0088 (7)	−0.0106 (6)
Br3	0.0217 (7)	0.0587 (9)	0.0434 (8)	−0.0044 (6)	−0.0010 (6)	−0.0045 (6)
Br4	0.0603 (11)	0.0393 (8)	0.1026 (14)	−0.0292 (8)	0.0334 (10)	−0.0129 (7)
Br5	0.0593 (10)	0.0580 (9)	0.0247 (7)	0.0085 (6)	0.0028 (6)	−0.0229 (7)
C1	0.023 (6)	0.043 (7)	0.017 (6)	0.013 (5)	0.010 (5)	0.014 (5)
C2	0.040 (7)	0.023 (6)	0.020 (6)	−0.001 (5)	0.002 (5)	0.000 (5)
C3	0.018 (6)	0.030 (6)	0.023 (6)	0.006 (5)	0.004 (5)	0.005 (5)
C4	0.008 (5)	0.038 (6)	0.027 (7)	−0.004 (5)	0.000 (5)	−0.002 (5)
C5	0.032 (7)	0.023 (6)	0.052 (8)	−0.005 (6)	0.005 (6)	0.002 (5)
C6	0.017 (6)	0.035 (7)	0.039 (8)	−0.005 (5)	0.009 (5)	0.004 (5)
C7	0.027 (6)	0.030 (6)	0.019 (6)	0.001 (5)	0.010 (5)	−0.014 (5)
C8	0.063 (10)	0.039 (8)	0.036 (8)	−0.010 (7)	0.017 (7)	−0.024 (7)
C9	0.073 (11)	0.046 (9)	0.029 (8)	−0.005 (7)	0.002 (8)	−0.028 (8)
C10	0.075 (11)	0.028 (7)	0.039 (9)	0.012 (6)	−0.019 (8)	−0.018 (7)
C11	0.051 (9)	0.034 (7)	0.034 (8)	0.006 (6)	−0.004 (7)	0.000 (6)
C12	0.017 (6)	0.019 (5)	0.027 (6)	0.003 (5)	0.000 (5)	0.003 (5)

Geometric parameters (Å, º)

C1—C6	1.538 (16)	C5—C6	1.553 (17)
C1—C2	1.544 (15)	C5—H5	0.98
C1—Br1	1.948 (11)	C6—C7	1.492 (16)
C1—H1	0.98	C6—H6	0.98
C2—C3	1.526 (15)	C7—C8	1.369 (16)
C2—Br2	1.948 (11)	C7—C12	1.393 (15)
C2—H2	0.98	C8—C9	1.36 (2)
C3—C12	1.511 (15)	C8—H8	0.93
C3—C4	1.543 (15)	C9—C10	1.34 (2)
C3—H3	0.98	C9—H9	0.93
C4—C5	1.568 (16)	C10—C11	1.397 (19)
C4—Br3	1.947 (10)	C10—H10	0.93
C5—Br4	1.943 (12)	C11—C12	1.338 (16)
C4—Br5	1.969 (11)	C11—H11	0.93
C6—C1—C2	108.8 (9)	C6—C5—H5	108.3
C6—C1—Br1	108.6 (7)	C4—C5—H5	108.3
C2—C1—Br1	116.6 (8)	Br4—C5—H5	108.3
C6—C1—H1	107.5	C7—C6—C1	110.9 (9)
C2—C1—H1	107.5	C7—C6—C5	110.7 (9)
Br1—C1—H1	107.5	C1—C6—C5	106.2 (9)
C3—C2—C1	109.4 (9)	C7—C6—H6	109.7
C3—C2—Br2	107.6 (7)	C1—C6—H6	109.7
C1—C2—Br2	116.9 (8)	C5—C6—H6	109.7
C3—C2—H2	107.5	C8—C7—C12	120.6 (12)
C1—C2—H2	107.5	C8—C7—C6	127.2 (12)
Br2—C2—H2	107.5	C12—C7—C6	112.1 (9)
C12—C3—C2	110.5 (9)	C9—C8—C7	117.5 (14)
C12—C3—C4	105.3 (9)	C9—C8—H8	121.2
C2—C3—C4	109.3 (8)	C7—C8—H8	121.2
C12—C3—H3	110.6	C10—C9—C8	122.8 (13)
C2—C3—H3	110.6	C10—C9—H9	118.6
C4—C3—H3	110.6	C8—C9—H9	118.6
C3—C4—C5	110.1 (9)	C9—C10—C11	119.3 (13)
C3—C4—Br3	108.0 (7)	C9—C10—H10	120.3
C5—C4—Br3	115.0 (7)	C11—C10—H10	120.3
C6—C5—Br4	108.9 (8)	C12—C11—C10	119.3 (14)
C4—C5—Br4	116.2 (8)	C12—C11—H11	120.4
C3—C4—Br5	111.6 (7)	C10—C11—H11	120.4
C5—C4—Br5	107.6 (8)	C11—C12—C7	120.3 (11)
Br3—C4—Br5	104.4 (5)	C11—C12—C3	126.6 (11)
C6—C5—C4	106.7 (9)	C7—C12—C3	113.1 (9)
C6—C1—C2—C3	2.0 (12)	C4—C5—C6—C7	−54.0 (12)
Br1—C1—C2—C3	125.2 (8)	Br4—C5—C6—C7	72.2 (10)
C6—C1—C2—Br2	−120.7 (9)	C4—C5—C6—C1	66.4 (11)
Br1—C1—C2—Br2	2.5 (11)	Br4—C5—C6—C1	−167.4 (7)
C1—C2—C3—C12	−56.1 (11)	C1—C6—C7—C8	123.4 (12)
Br2—C2—C3—C12	71.9 (10)	C5—C6—C7—C8	−119.0 (13)
C1—C2—C3—C4	59.3 (11)	C1—C6—C7—C12	−59.3 (13)
Br2—C2—C3—C4	−172.7 (7)	C5—C6—C7—C12	58.2 (12)
C12—C3—C4—C5	61.4 (11)	C12—C7—C8—C9	1.7 (18)
C2—C3—C4—C5	−57.3 (12)	C6—C7—C8—C9	178.7 (12)
C12—C3—C4—Br3	−65.0 (9)	C7—C8—C9—C10	1 (2)
C2—C3—C4—Br3	176.3 (7)	C8—C9—C10—C11	−3 (2)
C12—C3—C4—Br5	−179.2 (7)	C9—C10—C11—C12	3 (2)
C2—C3—C4—Br5	62.1 (10)	C10—C11—C12—C7	−0.6 (19)
C3—C4—C5—C6	−5.5 (12)	C10—C11—C12—C3	177.4 (11)
Br3—C4—C5—C6	116.9 (9)	C8—C7—C12—C11	−1.6 (17)
Br5—C4—C5—C6	−127.3 (8)	C6—C7—C12—C11	−179.1 (11)
C3—C4—C5—Br4	−127.2 (9)	C8—C7—C12—C3	−179.9 (10)
Br3—C4—C5—Br4	−4.8 (12)	C6—C7—C12—C3	2.7 (13)
Br5—C4—C5—Br4	111.0 (8)	C2—C3—C12—C11	−122.4 (13)
C2—C1—C6—C7	55.0 (12)	C4—C3—C12—C11	119.7 (13)
Br1—C1—C6—C7	−72.9 (10)	C2—C3—C12—C7	55.7 (12)
C2—C1—C6—C5	−65.3 (11)	C4—C3—C12—C7	−62.1 (11)
Br1—C1—C6—C5	166.8 (7)