(6RS,9SR)-6,7-Dibromo-1,2,3,4-tetra­hydro-1,4-methano­anthracene

Chen, K.-Y.; Chang, M.-J.; Fang, T.-C.

doi:10.1107/S1600536811013572

organic compounds

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ISSN: 2056-9890

Volume 67| Part 5| May 2011| Page o1147

doi:10.1107/S1600536811013572

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(6RS,9SR)-6,7-Dibromo-1,2,3,4-tetrahydro-1,4-methanoanthracene

Kew-Yu Chen,^a ^* Ming-Jen Chang ^a and Tzu-Chien Fang ^a

^aDepartment of Chemical Engineering, Feng Chia University, 40724 Taichung, Taiwan
^*Correspondence e-mail: kyuchen@fcu.edu.tw

(Received 26 March 2011; accepted 11 April 2011; online 16 April 2011)

The title compound, C₁₅H₁₂Br₂, comprises a norbornane unit having a dibromonaphthalene ring fused on one side. Both Br atoms are twisted slightly out of the plane of the naphthalene ring system with a Br—C—C—Br torsion angle of 5.3 (5)°. In the crystal, molecules are linked by weak intermolecular C—H⋯Br hydrogen bonds, forming an infinite C(9) chain along [110].

Related literature

For the spectroscopy of the title compound and its preparation, see: Chen et al. (2006 ). For the spectroscopy and electronic device applications of rigid oligo-norbornyl compounds, see: Chen et al. (2002 ); Chow et al. (2005 ); Lewis et al. (1997 ); Roest et al. (1996 ). For related structures, see: Çelik et al. (2006 ); Chiou et al. (2001 ); Chow et al. (1999 ); Lough et al. (2006 ). For the C—H⋯Br hydrogen bond, see: Desiraju & Steiner (2001 ); Farrugia et al. (2007 ); Kuś & Jones (2003 ); Yang et al. (2007 ). For puckering parameters, see: Cremer & Pople (1975 ). For graph-set theory, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₅H₁₂Br₂
M_r = 352.07
Monoclinic, C 2/c
a = 23.437 (3) Å
b = 6.3565 (8) Å
c = 18.416 (2) Å
β = 111.781 (2)°
V = 2547.6 (6) Å³
Z = 8
Mo Kα radiation
μ = 6.34 mm⁻¹
T = 297 K
0.56 × 0.48 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.399, T_max = 1.000
6895 measured reflections
2501 independent reflections
1817 reflections with I > 2σ(I)
R_int = 0.058

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.144
S = 0.96
2501 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 1.12 e Å⁻³
Δρ_min = −1.09 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8A⋯Br2ⁱ	0.97	3.00 (1)	3.843 (16)	146 (1)
Symmetry code: (i) $[x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ .

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811013572/nr2004sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811013572/nr2004Isup2.hkl

checkCIF report

Comment top

Electron donor (D)–acceptor (A) chromophores linked by rigid, covalent spacers (S), forming D–S–A dyads, have attracted considerable attention due to their potential applications in the design of molecular devices (Lewis et al., 1997; Roest et al., 1996). Numerous types of spacers have been reported (Chiou et al., 2001; Chow et al., 1999). However, rigid linear rod-shaped structures are not commonly seen. The highly symmetrical structures reduce the complexity due to the constraint of geometrical and conformational variations. The rates of photoinduced electron transfer reactions across linearly fused oligo-norbornyl spacer groups have been estimated (Chen et al., 2002; Chow et al., 2005). The ET rates were found to correlate well with both D–A distance and solvent polarities. Atoms C6 and C9 of the title compound are chiral centers, but their relative configurations are opposite (6R,9S or 6S,9R). The racemate was prepared as a model compound for investigations of the intramolecular electron transfer reactions (Chen et al., 2006).

The ORTEP diagram of the title compound is shown in Figure 1. The puckering parameters (Cremer & Pople, 1975) of the five-membered rings A (C5/C6/C15/C9/C10) and B (C6–C9/C15) are Q₂ = 0.560 (6)Å and ϕ₂ = 71.0 (5)°, and Q₂ = 0.602 (6)Å and ϕ₂ = 144.7 (6)°, respectively. These results are slightly different from those of previous studies on other norbornane derivatives (Çelik, et al., 2006; Lough, et al., 2006). In addition, the naphthalene ring is essentially planar with a maximum deviation of 0.052 (2)Å for atom C5. Whereas both bromine atoms are slightly twisted out of the plane of the naphthalene ring (5.3 (5)° of Br1—C1—C14—Br2, Table 1). In the crystal structure (Figure 2), the molecules are linked by weak intermolecular C—H···Br (2.998 (2)Å of C8—H8A···Br2 distance and 146 (1)° of C8—H8A—Br2, Table 2) hydrogen bonds (Desiraju et al., 2001; Farrugia et al., 2007; Kuś et al., 2003; Yang et al., 2007) to form an infinite two-dimensional chain, generating a C(9) motif (Bernstein et al., 1995).

Related literature top

For the spectroscopy of the title compound and its preparation, see: Chen et al. (2006). For the spectroscopy and electronic device applications of rigid oligo-norbornyl compounds, see: Chen et al. (2002); Chow et al. (2005); Lewis et al. (1997); Roest et al. (1996). For related structures, see: Çelik et al. (2006); Chiou et al. (2001); Chow et al. (1999); Lough et al. (2006). For the C—H···Br hydrogen bond, see: Desiraju & Steiner (2001); Farrugia et al. (2007); Kuś & Jones (2003); Yang et al. (2007). For general definition of ring puckering coordinates, see: Cremer & Pople (1975). For graph-set theory, see: Bernstein et al. (1995).

Experimental top

A mixture of α,α,α',α'-4,5- hexabromo-o-xylene (4.3 mmol), norbornene (4.3 mmol), sodium iodide (30 mmol), and dry DMF (50 ml) was stirred at 65 ^oC for 24 h. The reaction mixture was poured into cold water (350 ml) containing sodium bisfulfite (5.0 g). The yellow precipitate was purified by chromatography (silica gel column, hexane:ethyl acetate = 6:1) and finally by recrystallization. Colorless needle-shaped crystals suitable for the crystallographic studies reported here were isolated over a period of five weeks by slow evaporation from a chloroform solution.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids.
	Fig. 2. A section of the crystal packing of the title compound, viewed along the b axis.

(6RS,9SR)-6,7- dibromotetracyclo[10.2.1.0^2,11.0^4,9]pentadeca-2,4(9),5,7,10-pentaene top

Crystal data top

C₁₅H₁₂Br₂	F(000) = 1376
M_r = 352.07	D_x = 1.836 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2464 reflections
a = 23.437 (3) Å	θ = 3.3–25.5°
b = 6.3565 (8) Å	µ = 6.34 mm⁻¹
c = 18.416 (2) Å	T = 297 K
β = 111.781 (2)°	Parallelepiped, colorless
V = 2547.6 (6) Å³	0.56 × 0.48 × 0.20 mm
Z = 8

Data collection top

Bruker SMART CCD area-detector diffractometer	2501 independent reflections
Radiation source: fine-focus sealed tube	1817 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.058
ϕ and ω scans	θ_max = 26.1°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −19→28
T_min = 0.399, T_max = 1.000	k = −7→7
6895 measured reflections	l = −22→21

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.144	H-atom parameters constrained
S = 0.96	w = 1/[σ²(F_o²) + (0.095P)²] where P = (F_o² + 2F_c²)/3
2501 reflections	(Δ/σ)_max < 0.001
154 parameters	Δρ_max = 1.12 e Å⁻³
0 restraints	Δρ_min = −1.09 e Å⁻³

Crystal data top

C₁₅H₁₂Br₂	V = 2547.6 (6) Å³
M_r = 352.07	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 23.437 (3) Å	µ = 6.34 mm⁻¹
b = 6.3565 (8) Å	T = 297 K
c = 18.416 (2) Å	0.56 × 0.48 × 0.20 mm
β = 111.781 (2)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2501 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1817 reflections with I > 2σ(I)
T_min = 0.399, T_max = 1.000	R_int = 0.058
6895 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.144	H-atom parameters constrained
S = 0.96	Δρ_max = 1.12 e Å⁻³
2501 reflections	Δρ_min = −1.09 e Å⁻³
154 parameters

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	U_iso*/U_eq
Br1	0.02569 (2)	0.67170 (9)	0.16329 (3)	0.0637 (2)
Br2	0.02816 (3)	0.21416 (10)	0.07270 (4)	0.0725 (3)
C1	0.0959 (2)	0.5881 (7)	0.1431 (2)	0.0420 (10)
C2	0.1462 (2)	0.7148 (7)	0.1649 (2)	0.0451 (10)
H2A	0.1447	0.8436	0.1881	0.054*
C3	0.2004 (2)	0.6583 (7)	0.1536 (2)	0.0406 (10)
C4	0.2517 (2)	0.7938 (7)	0.1720 (2)	0.0451 (11)
H4A	0.2510	0.9253	0.1938	0.054*
C5	0.3020 (2)	0.7309 (7)	0.1576 (2)	0.0439 (10)
C6	0.3608 (2)	0.8382 (8)	0.1631 (3)	0.0545 (13)
H6A	0.3726	0.9605	0.1979	0.065*
C7	0.3561 (2)	0.8766 (9)	0.0789 (3)	0.0583 (13)
H7A	0.3178	0.9466	0.0488	0.070*
H7B	0.3900	0.9621	0.0779	0.070*
C8	0.3584 (2)	0.6567 (8)	0.0465 (3)	0.0595 (14)
H8A	0.3932	0.6426	0.0302	0.071*
H8B	0.3209	0.6252	0.0025	0.071*
C9	0.3656 (2)	0.5124 (9)	0.1171 (3)	0.0612 (13)
H9A	0.3814	0.3705	0.1151	0.073*
C10	0.3047 (2)	0.5253 (7)	0.1275 (3)	0.0454 (10)
C11	0.2564 (2)	0.3915 (8)	0.1093 (3)	0.0513 (11)
H11A	0.2586	0.2587	0.0893	0.062*
C12	0.2025 (2)	0.4553 (6)	0.1210 (2)	0.0387 (9)
C13	0.1496 (2)	0.3277 (7)	0.0989 (3)	0.0479 (11)
H13A	0.1504	0.1961	0.0772	0.057*
C14	0.0971 (2)	0.3921 (7)	0.1085 (2)	0.0454 (10)
C15	0.4058 (2)	0.6541 (10)	0.1856 (3)	0.0692 (16)
H15A	0.4115	0.5958	0.2365	0.083*
H15B	0.4452	0.6885	0.1826	0.083*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0470 (3)	0.0745 (4)	0.0825 (4)	−0.0007 (3)	0.0389 (3)	0.0001 (3)
Br2	0.0554 (4)	0.0786 (4)	0.0901 (5)	−0.0332 (3)	0.0345 (3)	−0.0187 (3)
C1	0.038 (2)	0.052 (3)	0.041 (2)	−0.005 (2)	0.021 (2)	0.0023 (18)
C2	0.046 (3)	0.048 (3)	0.048 (3)	−0.007 (2)	0.025 (2)	−0.0068 (19)
C3	0.043 (2)	0.045 (2)	0.038 (2)	−0.006 (2)	0.020 (2)	−0.0012 (18)
C4	0.046 (3)	0.054 (3)	0.038 (2)	−0.009 (2)	0.019 (2)	−0.0092 (18)
C5	0.037 (2)	0.056 (3)	0.038 (2)	−0.013 (2)	0.013 (2)	−0.0047 (19)
C6	0.044 (3)	0.072 (3)	0.049 (3)	−0.023 (2)	0.018 (2)	−0.011 (2)
C7	0.049 (3)	0.072 (3)	0.058 (3)	−0.009 (3)	0.024 (2)	0.008 (2)
C8	0.041 (3)	0.087 (4)	0.059 (3)	−0.011 (3)	0.028 (2)	−0.011 (3)
C9	0.041 (3)	0.065 (3)	0.084 (4)	0.004 (3)	0.031 (3)	0.007 (3)
C10	0.034 (2)	0.056 (3)	0.048 (2)	−0.001 (2)	0.017 (2)	0.003 (2)
C11	0.050 (3)	0.042 (2)	0.068 (3)	−0.001 (2)	0.030 (2)	−0.003 (2)
C12	0.039 (2)	0.041 (2)	0.039 (2)	−0.0049 (19)	0.0171 (19)	−0.0002 (17)
C13	0.052 (3)	0.040 (2)	0.059 (3)	−0.011 (2)	0.029 (2)	−0.0076 (19)
C14	0.041 (2)	0.052 (3)	0.044 (2)	−0.013 (2)	0.017 (2)	0.0022 (19)
C15	0.036 (3)	0.107 (5)	0.061 (3)	−0.003 (3)	0.013 (2)	0.019 (3)

Geometric parameters (Å, º) top

Br1—C1	1.892 (4)	C7—H7A	0.9700
Br2—C14	1.881 (4)	C7—H7B	0.9700
C1—C2	1.359 (6)	C8—C9	1.548 (7)
C1—C14	1.405 (6)	C8—H8A	0.9700
C2—C3	1.407 (6)	C8—H8B	0.9700
C2—H2A	0.9300	C9—C10	1.512 (6)
C3—C12	1.432 (6)	C9—C15	1.552 (8)
C3—C4	1.415 (6)	C9—H9A	0.9800
C4—C5	1.363 (6)	C10—C11	1.355 (7)
C4—H4A	0.9300	C11—C12	1.417 (6)
C5—C10	1.430 (7)	C11—H11A	0.9300
C5—C6	1.506 (6)	C12—C13	1.409 (6)
C6—C15	1.526 (8)	C13—C14	1.368 (7)
C6—C7	1.533 (6)	C13—H13A	0.9300
C6—H6A	0.9800	C15—H15A	0.9700
C7—C8	1.529 (7)	C15—H15B	0.9700

C2—C1—C14	119.8 (4)	C7—C8—H8B	111.2
C2—C1—Br1	119.8 (3)	C9—C8—H8B	111.2
C14—C1—Br1	120.3 (3)	H8A—C8—H8B	109.1
C1—C2—C3	122.4 (4)	C10—C9—C8	105.1 (4)
C1—C2—H2A	118.8	C10—C9—C15	100.5 (4)
C3—C2—H2A	118.8	C8—C9—C15	100.6 (4)
C12—C3—C4	119.3 (4)	C10—C9—H9A	116.1
C12—C3—C2	117.8 (4)	C8—C9—H9A	116.1
C4—C3—C2	122.9 (4)	C15—C9—H9A	116.1
C5—C4—C3	119.7 (4)	C11—C10—C5	121.1 (4)
C5—C4—H4A	120.1	C11—C10—C9	132.6 (5)
C3—C4—H4A	120.1	C5—C10—C9	106.1 (4)
C4—C5—C10	120.6 (4)	C10—C11—C12	119.5 (4)
C4—C5—C6	133.7 (4)	C10—C11—H11A	120.2
C10—C5—C6	105.7 (4)	C12—C11—H11A	120.2
C5—C6—C15	101.2 (4)	C11—C12—C3	119.6 (4)
C5—C6—C7	106.4 (4)	C11—C12—C13	122.0 (4)
C15—C6—C7	100.4 (4)	C3—C12—C13	118.4 (4)
C5—C6—H6A	115.6	C14—C13—C12	121.8 (4)
C15—C6—H6A	115.6	C14—C13—H13A	119.1
C7—C6—H6A	115.6	C12—C13—H13A	119.1
C8—C7—C6	104.5 (4)	C13—C14—C1	119.7 (4)
C8—C7—H7A	110.9	C13—C14—Br2	118.1 (3)
C6—C7—H7A	110.9	C1—C14—Br2	122.1 (4)
C8—C7—H7B	110.9	C6—C15—C9	94.3 (4)
C6—C7—H7B	110.9	C6—C15—H15A	112.9
H7A—C7—H7B	108.9	C9—C15—H15A	112.9
C7—C8—C9	102.8 (4)	C6—C15—H15B	112.9
C7—C8—H8A	111.2	C9—C15—H15B	112.9
C9—C8—H8A	111.2	H15A—C15—H15B	110.3

C14—C1—C2—C3	0.5 (7)	C8—C9—C10—C5	−71.4 (5)
Br1—C1—C2—C3	178.0 (3)	C15—C9—C10—C5	32.6 (5)
C1—C2—C3—C12	−2.8 (6)	C5—C10—C11—C12	−0.6 (7)
C1—C2—C3—C4	176.3 (4)	C9—C10—C11—C12	−175.1 (5)
C12—C3—C4—C5	0.8 (6)	C10—C11—C12—C3	−1.5 (6)
C2—C3—C4—C5	−178.2 (4)	C10—C11—C12—C13	176.2 (4)
C3—C4—C5—C10	−2.9 (6)	C4—C3—C12—C11	1.4 (6)
C3—C4—C5—C6	173.9 (4)	C2—C3—C12—C11	−179.5 (4)
C4—C5—C6—C15	147.7 (5)	C4—C3—C12—C13	−176.3 (4)
C10—C5—C6—C15	−35.1 (5)	C2—C3—C12—C13	2.8 (6)
C4—C5—C6—C7	−107.8 (6)	C11—C12—C13—C14	−178.3 (4)
C10—C5—C6—C7	69.4 (5)	C3—C12—C13—C14	−0.6 (6)
C5—C6—C7—C8	−68.1 (5)	C12—C13—C14—C1	−1.7 (7)
C15—C6—C7—C8	36.9 (5)	C12—C13—C14—Br2	177.3 (3)
C6—C7—C8—C9	−1.0 (5)	C2—C1—C14—C13	1.8 (6)
C7—C8—C9—C10	69.5 (5)	Br1—C1—C14—C13	−175.7 (3)
C7—C8—C9—C15	−34.6 (5)	C2—C1—C14—Br2	−177.1 (3)
C4—C5—C10—C11	2.9 (7)	Br1—C1—C14—Br2	5.3 (5)
C6—C5—C10—C11	−174.7 (4)	C5—C6—C15—C9	52.5 (4)
C4—C5—C10—C9	178.7 (4)	C7—C6—C15—C9	−56.7 (4)
C6—C5—C10—C9	1.0 (5)	C10—C9—C15—C6	−51.5 (4)
C8—C9—C10—C11	103.6 (6)	C8—C9—C15—C6	56.3 (4)
C15—C9—C10—C11	−152.3 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···Br2ⁱ	0.97	3.00 (1)	3.843 (16)	146 (1)

Symmetry code: (i) x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₂Br₂
M_r	352.07
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	297
a, b, c (Å)	23.437 (3), 6.3565 (8), 18.416 (2)
β (°)	111.781 (2)
V (Å³)	2547.6 (6)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	6.34
Crystal size (mm)	0.56 × 0.48 × 0.20

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.399, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	6895, 2501, 1817
R_int	0.058
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.144, 0.96
No. of reflections	2501
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.12, −1.09

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···Br2ⁱ	0.972	3.00 (1)	3.843 (16)	146 (1)

Symmetry code: (i) x+1/2, y+1/2, z.

Acknowledgements

Financial support from the National Science Council of the Republic of China is gratefully acknowledged.

References

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