5,8-Dibromo-14,15,17,18-tetra­methyl-2,11-dithia­[3.3]paracyclo­phane

Huang, S.; Wang, Q.

doi:10.1107/S1600536810026760

organic compounds

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ISSN: 2056-9890

Volume 66| Part 8| August 2010| Page o1993

https://doi.org/10.1107/S1600536810026760

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5,8-Dibromo-14,15,17,18-tetramethyl-2,11-dithia[3.3]paracyclophane

Shuyuan Huang ^a ^* and Qianqian Wang ^a

^aKey Laboratory of Pesticides and Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
^*Correspondence e-mail: jxsdhsy@163.com

(Received 26 June 2010; accepted 6 July 2010; online 10 July 2010)

In the title molecule [systematic name: 1²,1⁵-dibromo-5²,5³,5⁵,5⁶-tetramethyl-3,7-dithia-1,5(1,4)-dibenzenacyclooctaphane], C₂₀H₂₂Br₂S₂, the distance between the centroids of the two benzene rings is 3.326 (4) Å, and their mean planes are almost parallel, forming a dihedral angle of 1.05 (7)°. The crystal packing exhibits no intermolecular contacts shorter than the sum of van der Waals radii.

Related literature

For the preparation of the title compound, see: Wang et al. (2006 ). For the crystal structures of related compounds, see: Sun et al. (2008 ); Clément et al. (2009 ).

Experimental

Crystal data

C₂₀H₂₂Br₂S₂
M_r = 486.32
Monoclinic, P 2₁ /c
a = 15.298 (3) Å
b = 12.340 (2) Å
c = 10.0160 (18) Å
β = 91.864 (3)°
V = 1889.8 (6) Å³
Z = 4
Mo Kα radiation
μ = 4.51 mm⁻¹
T = 298 K
0.23 × 0.20 × 0.20 mm

Data collection

Bruker SMART APEX diffractometer
12364 measured reflections
3922 independent reflections
2690 reflections with I > 2σ(I)
R_int = 0.075

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.099
S = 0.94
3922 reflections
221 parameters
H-atom parameters constrained
Δρ_max = 0.51 e Å⁻³
Δρ_min = −0.31 e Å⁻³

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

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810026760/cv2738sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810026760/cv2738Isup2.hkl

checkCIF report

Comment top

As a contribution to a structural studies of paracyclophane compounds (Sun et al., 2008; Clément et al., 2009), we present here the crystal structure of the title compound (I).

In (I) (Fig. 1), the distance between the centroids of two benzene rings is 3.326 (4) Å, and their mean planes are almost parallel forming a dihedral angle of 1.05 (7)°. The crystal packing exhibits no intermolecular contacts shorter than the sum of van der Waals radii

Related literature top

For the preparation of the title compound, see: Wang et al. (2006). For the crystal structures of related compounds, see: Sun et al. (2008); Clément et al. (2009).

Experimental top

The title compound has been prepared following the known procedure (Wang et al., 2006). A solution with equimolar amounts of 2,5-dibromo-1,4-bis(mercaptomethyl)benzene and 1,4-dibromomethyl-2,3,5,6-tetramethylbenzene in degassed THF(500 mL) was added dropwise under N₂ over 12 h to a refluxing solution of potassium carbonate(5 equiv) in EtOH(1.2L). After an additional 2 h at the reflux temperature, the mixture was cooled and the solvent were removed. The resulting residue was treated with CH₂Cl₂(300 mL) and water(300 mL). The organic phase was separated, the aqueous extracted with CH₂Cl₂ three times. The combined organic layers was dried over Na₂SO₄,then solvent was removed, and the resulting solid was chromatographed on silica gel using CH₂Cl₂/petroleum ether(1:1,v/v) as eluent. The product was further purified by recrystallization from toluene.

Structure description top

As a contribution to a structural studies of paracyclophane compounds (Sun et al., 2008; Clément et al., 2009), we present here the crystal structure of the title compound (I).

For the preparation of the title compound, see: Wang et al. (2006). For the crystal structures of related compounds, see: Sun et al. (2008); Clément et al. (2009).

Computing details top

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

Figures top

Fig. 1. A view of (I), showing the atom-labelling scheme, with displacement ellipsoids drawn at the 50% probability level.

1²,1⁵-Dibromo-5²,5³,5⁵,5⁶-tetramethyl-3,7-dithia- 1,5(1,4)-dibenzenacyclooctaphane top

Crystal data top

C₂₀H₂₂Br₂S₂	F(000) = 976
M_r = 486.32	D_x = 1.709 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3874 reflections
a = 15.298 (3) Å	θ = 2.6–23.9°
b = 12.340 (2) Å	µ = 4.51 mm⁻¹
c = 10.0160 (18) Å	T = 298 K
β = 91.864 (3)°	Block, colourless
V = 1889.8 (6) Å³	0.23 × 0.20 × 0.20 mm
Z = 4

Data collection top

Bruker SMART APEX diffractometer	2690 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.075
Graphite monochromator	θ_max = 26.5°, θ_min = 2.1°
phi and ω scans	h = −12→19
12364 measured reflections	k = −15→14
3922 independent reflections	l = −12→12

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.099	H-atom parameters constrained
S = 0.94	w = 1/[σ²(F_o²) + (0.049P)²] where P = (F_o² + 2F_c²)/3
3922 reflections	(Δ/σ)_max = 0.013
221 parameters	Δρ_max = 0.51 e Å⁻³
0 restraints	Δρ_min = −0.31 e Å⁻³

Crystal data top

C₂₀H₂₂Br₂S₂	V = 1889.8 (6) Å³
M_r = 486.32	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 15.298 (3) Å	µ = 4.51 mm⁻¹
b = 12.340 (2) Å	T = 298 K
c = 10.0160 (18) Å	0.23 × 0.20 × 0.20 mm
β = 91.864 (3)°

Data collection top

Bruker SMART APEX diffractometer	2690 reflections with I > 2σ(I)
12364 measured reflections	R_int = 0.075
3922 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.099	H-atom parameters constrained
S = 0.94	Δρ_max = 0.51 e Å⁻³
3922 reflections	Δρ_min = −0.31 e Å⁻³
221 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	0.63291 (3)	−0.24847 (3)	0.69722 (4)	0.06216 (15)
Br2	0.86653 (3)	0.03415 (3)	1.12714 (4)	0.06978 (17)
C1	0.7941 (2)	−0.1625 (2)	0.8090 (3)	0.0407 (8)
C2	0.7035 (2)	−0.1602 (2)	0.8134 (3)	0.0398 (7)
C3	0.6607 (2)	−0.0921 (3)	0.8980 (3)	0.0445 (8)
H3	0.5998	−0.0911	0.8961	0.053*
C4	0.7068 (2)	−0.0249 (2)	0.9864 (3)	0.0436 (8)
C5	0.7961 (2)	−0.0389 (2)	0.9945 (3)	0.0434 (8)
C6	0.8387 (2)	−0.1043 (2)	0.9067 (3)	0.0448 (8)
H6	0.8994	−0.1094	0.9134	0.054*
C7	0.8438 (3)	−0.2189 (3)	0.7015 (4)	0.0579 (10)
H7A	0.8025	−0.2425	0.6320	0.069*
H7B	0.8713	−0.2832	0.7396	0.069*
C8	0.8677 (2)	−0.0337 (3)	0.5289 (3)	0.0493 (9)
H8A	0.9104	0.0117	0.4863	0.059*
H8B	0.8339	−0.0700	0.4585	0.059*
C9	0.8064 (2)	0.0394 (2)	0.6037 (3)	0.0336 (7)
C10	0.7159 (2)	0.0343 (2)	0.5758 (3)	0.0351 (7)
C11	0.65953 (19)	0.0939 (2)	0.6546 (3)	0.0344 (7)
C12	0.69283 (19)	0.1594 (2)	0.7578 (3)	0.0339 (7)
C13	0.7842 (2)	0.1727 (2)	0.7759 (3)	0.0340 (7)
C14	0.84008 (19)	0.1132 (2)	0.6990 (3)	0.0351 (7)
C15	0.6794 (2)	−0.0317 (3)	0.4589 (3)	0.0533 (9)
H15A	0.6190	−0.0132	0.4423	0.080*
H15B	0.6840	−0.1075	0.4796	0.080*
H15C	0.7119	−0.0162	0.3808	0.080*
C16	0.5615 (2)	0.0846 (3)	0.6279 (4)	0.0524 (9)
H16A	0.5425	0.0129	0.6503	0.079*
H16B	0.5482	0.0984	0.5351	0.079*
H16C	0.5318	0.1366	0.6815	0.079*
C17	0.9379 (2)	0.1285 (3)	0.7171 (4)	0.0555 (9)
H17A	0.9518	0.2041	0.7109	0.083*
H17B	0.9671	0.0894	0.6487	0.083*
H17C	0.9569	0.1016	0.8032	0.083*
C18	0.8205 (3)	0.2505 (3)	0.8816 (4)	0.0532 (9)
H18A	0.8832	0.2463	0.8850	0.080*
H18B	0.7986	0.2313	0.9671	0.080*
H18C	0.8028	0.3231	0.8593	0.080*
C19	0.6313 (2)	0.2168 (3)	0.8503 (4)	0.0478 (8)
H19A	0.5883	0.2561	0.7959	0.057*
H19B	0.6647	0.2697	0.9021	0.057*
C20	0.6574 (3)	0.0609 (3)	1.0634 (4)	0.0615 (10)
H20A	0.6990	0.1141	1.0978	0.074*
H20B	0.6310	0.0265	1.1393	0.074*
S1	0.92690 (6)	−0.13702 (8)	0.62621 (10)	0.0536 (2)
S2	0.57294 (6)	0.13011 (8)	0.96634 (10)	0.0572 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0655 (3)	0.0568 (3)	0.0643 (3)	−0.01722 (19)	0.0036 (2)	−0.00873 (18)
Br2	0.0857 (3)	0.0680 (3)	0.0542 (2)	0.0013 (2)	−0.0199 (2)	−0.00657 (19)
C1	0.046 (2)	0.0305 (16)	0.0458 (18)	0.0047 (15)	0.0098 (15)	0.0078 (14)
C2	0.049 (2)	0.0323 (16)	0.0383 (16)	−0.0038 (15)	0.0036 (14)	0.0041 (13)
C3	0.042 (2)	0.046 (2)	0.0456 (18)	−0.0015 (16)	0.0131 (15)	0.0034 (15)
C4	0.057 (2)	0.0401 (18)	0.0345 (16)	0.0056 (16)	0.0110 (15)	0.0066 (14)
C5	0.056 (2)	0.0407 (18)	0.0332 (16)	−0.0002 (16)	−0.0047 (15)	0.0063 (14)
C6	0.0415 (19)	0.0441 (19)	0.0489 (19)	0.0059 (15)	0.0015 (16)	0.0058 (16)
C7	0.059 (2)	0.0427 (19)	0.073 (3)	0.0030 (17)	0.021 (2)	−0.0133 (18)
C8	0.050 (2)	0.055 (2)	0.0434 (19)	0.0080 (17)	0.0094 (16)	0.0000 (15)
C9	0.0344 (18)	0.0372 (16)	0.0298 (14)	0.0046 (13)	0.0075 (12)	0.0063 (12)
C10	0.0409 (19)	0.0344 (16)	0.0301 (14)	−0.0028 (14)	−0.0002 (13)	0.0044 (12)
C11	0.0294 (17)	0.0383 (17)	0.0354 (15)	−0.0014 (13)	0.0021 (13)	0.0062 (13)
C12	0.0345 (17)	0.0303 (15)	0.0371 (15)	0.0023 (13)	0.0063 (13)	0.0041 (12)
C13	0.0367 (18)	0.0319 (15)	0.0333 (15)	−0.0031 (14)	−0.0006 (13)	0.0025 (12)
C14	0.0275 (16)	0.0396 (17)	0.0380 (16)	−0.0027 (13)	0.0004 (13)	0.0107 (13)
C15	0.052 (2)	0.057 (2)	0.050 (2)	−0.0062 (18)	−0.0023 (17)	−0.0121 (17)
C16	0.0309 (19)	0.064 (2)	0.062 (2)	−0.0022 (17)	−0.0018 (16)	−0.0051 (18)
C17	0.0326 (19)	0.065 (2)	0.068 (2)	−0.0055 (17)	−0.0016 (17)	−0.0039 (19)
C18	0.058 (2)	0.052 (2)	0.0492 (19)	−0.0119 (17)	−0.0032 (17)	−0.0060 (17)
C19	0.046 (2)	0.0409 (18)	0.057 (2)	0.0046 (16)	0.0119 (17)	−0.0045 (16)
C20	0.080 (3)	0.061 (2)	0.044 (2)	0.009 (2)	0.0095 (19)	−0.0028 (17)
S1	0.0425 (5)	0.0564 (6)	0.0626 (6)	0.0154 (4)	0.0150 (4)	0.0023 (4)
S2	0.0486 (6)	0.0601 (6)	0.0643 (6)	0.0107 (5)	0.0255 (5)	0.0004 (5)

Geometric parameters (Å, º) top

Br1—C2	1.904 (3)	C11—C16	1.519 (4)
Br2—C5	1.909 (3)	C12—C13	1.413 (4)
C1—C6	1.378 (4)	C12—C19	1.517 (4)
C1—C2	1.388 (4)	C13—C14	1.381 (4)
C1—C7	1.509 (5)	C13—C18	1.521 (4)
C2—C3	1.374 (4)	C14—C17	1.514 (4)
C3—C4	1.389 (5)	C15—H15A	0.9600
C3—H3	0.9300	C15—H15B	0.9600
C4—C5	1.377 (5)	C15—H15C	0.9600
C4—C20	1.524 (5)	C16—H16A	0.9600
C5—C6	1.373 (5)	C16—H16B	0.9600
C6—H6	0.9300	C16—H16C	0.9600
C7—S1	1.808 (4)	C17—H17A	0.9600
C7—H7A	0.9700	C17—H17B	0.9600
C7—H7B	0.9700	C17—H17C	0.9600
C8—C9	1.516 (4)	C18—H18A	0.9600
C8—S1	1.826 (3)	C18—H18B	0.9600
C8—H8A	0.9700	C18—H18C	0.9600
C8—H8B	0.9700	C19—S2	1.833 (4)
C9—C14	1.405 (4)	C19—H19A	0.9700
C9—C10	1.405 (4)	C19—H19B	0.9700
C10—C11	1.397 (4)	C20—S2	1.807 (4)
C10—C15	1.518 (4)	C20—H20A	0.9700
C11—C12	1.396 (4)	C20—H20B	0.9700

C6—C1—C2	116.1 (3)	C14—C13—C18	120.3 (3)
C6—C1—C7	119.9 (3)	C12—C13—C18	120.0 (3)
C2—C1—C7	124.0 (3)	C13—C14—C9	120.3 (3)
C3—C2—C1	121.9 (3)	C13—C14—C17	119.7 (3)
C3—C2—Br1	117.0 (3)	C9—C14—C17	120.1 (3)
C1—C2—Br1	121.0 (2)	C10—C15—H15A	109.5
C2—C3—C4	121.0 (3)	C10—C15—H15B	109.5
C2—C3—H3	119.5	H15A—C15—H15B	109.5
C4—C3—H3	119.5	C10—C15—H15C	109.5
C5—C4—C3	116.4 (3)	H15A—C15—H15C	109.5
C5—C4—C20	124.4 (3)	H15B—C15—H15C	109.5
C3—C4—C20	119.2 (3)	C11—C16—H16A	109.5
C6—C5—C4	121.8 (3)	C11—C16—H16B	109.5
C6—C5—Br2	117.0 (3)	H16A—C16—H16B	109.5
C4—C5—Br2	121.2 (3)	C11—C16—H16C	109.5
C5—C6—C1	121.8 (3)	H16A—C16—H16C	109.5
C5—C6—H6	119.1	H16B—C16—H16C	109.5
C1—C6—H6	119.1	C14—C17—H17A	109.5
C1—C7—S1	114.7 (2)	C14—C17—H17B	109.5
C1—C7—H7A	108.6	H17A—C17—H17B	109.5
S1—C7—H7A	108.6	C14—C17—H17C	109.5
C1—C7—H7B	108.6	H17A—C17—H17C	109.5
S1—C7—H7B	108.6	H17B—C17—H17C	109.5
H7A—C7—H7B	107.6	C13—C18—H18A	109.5
C9—C8—S1	117.1 (2)	C13—C18—H18B	109.5
C9—C8—H8A	108.0	H18A—C18—H18B	109.5
S1—C8—H8A	108.0	C13—C18—H18C	109.5
C9—C8—H8B	108.0	H18A—C18—H18C	109.5
S1—C8—H8B	108.0	H18B—C18—H18C	109.5
H8A—C8—H8B	107.3	C12—C19—S2	116.1 (2)
C14—C9—C10	120.1 (3)	C12—C19—H19A	108.3
C14—C9—C8	120.2 (3)	S2—C19—H19A	108.3
C10—C9—C8	119.8 (3)	C12—C19—H19B	108.3
C11—C10—C9	119.1 (3)	S2—C19—H19B	108.3
C11—C10—C15	120.0 (3)	H19A—C19—H19B	107.4
C9—C10—C15	120.9 (3)	C4—C20—S2	114.4 (2)
C12—C11—C10	120.4 (3)	C4—C20—H20A	108.7
C12—C11—C16	120.5 (3)	S2—C20—H20A	108.7
C10—C11—C16	119.0 (3)	C4—C20—H20B	108.7
C11—C12—C13	119.8 (3)	S2—C20—H20B	108.7
C11—C12—C19	120.2 (3)	H20A—C20—H20B	107.6
C13—C12—C19	119.9 (3)	C7—S1—C8	105.64 (18)
C14—C13—C12	119.7 (3)	C20—S2—C19	105.24 (19)

C6—C1—C2—C3	8.7 (4)	C9—C10—C11—C16	−177.5 (3)
C7—C1—C2—C3	−167.8 (3)	C15—C10—C11—C16	4.6 (4)
C6—C1—C2—Br1	−173.4 (2)	C10—C11—C12—C13	5.2 (4)
C7—C1—C2—Br1	10.1 (4)	C16—C11—C12—C13	−176.0 (3)
C1—C2—C3—C4	−2.1 (5)	C10—C11—C12—C19	−175.0 (3)
Br1—C2—C3—C4	179.9 (2)	C16—C11—C12—C19	3.8 (4)
C2—C3—C4—C5	−6.9 (5)	C11—C12—C13—C14	−5.7 (4)
C2—C3—C4—C20	171.0 (3)	C19—C12—C13—C14	174.5 (3)
C3—C4—C5—C6	9.1 (5)	C11—C12—C13—C18	175.4 (3)
C20—C4—C5—C6	−168.6 (3)	C19—C12—C13—C18	−4.4 (4)
C3—C4—C5—Br2	−171.9 (2)	C12—C13—C14—C9	−0.4 (4)
C20—C4—C5—Br2	10.3 (4)	C18—C13—C14—C9	178.5 (3)
C4—C5—C6—C1	−2.5 (5)	C12—C13—C14—C17	179.2 (3)
Br2—C5—C6—C1	178.5 (2)	C18—C13—C14—C17	−2.0 (4)
C2—C1—C6—C5	−6.5 (4)	C10—C9—C14—C13	7.0 (4)
C7—C1—C6—C5	170.2 (3)	C8—C9—C14—C13	−174.0 (3)
C6—C1—C7—S1	−46.5 (4)	C10—C9—C14—C17	−172.5 (3)
C2—C1—C7—S1	130.0 (3)	C8—C9—C14—C17	6.4 (4)
S1—C8—C9—C14	66.8 (4)	C11—C12—C19—S2	70.2 (3)
S1—C8—C9—C10	−114.2 (3)	C13—C12—C19—S2	−110.0 (3)
C14—C9—C10—C11	−7.5 (4)	C5—C4—C20—S2	136.9 (3)
C8—C9—C10—C11	173.5 (3)	C3—C4—C20—S2	−40.8 (4)
C14—C9—C10—C15	170.4 (3)	C1—C7—S1—C8	−69.5 (3)
C8—C9—C10—C15	−8.5 (4)	C9—C8—S1—C7	58.3 (3)
C9—C10—C11—C12	1.4 (4)	C4—C20—S2—C19	−71.1 (3)
C15—C10—C11—C12	−176.5 (3)	C12—C19—S2—C20	58.3 (3)

Experimental details

Crystal data
Chemical formula	C₂₀H₂₂Br₂S₂
M_r	486.32
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	15.298 (3), 12.340 (2), 10.0160 (18)
β (°)	91.864 (3)
V (Å³)	1889.8 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	4.51
Crystal size (mm)	0.23 × 0.20 × 0.20

Data collection
Diffractometer	Bruker SMART APEX
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	12364, 3922, 2690
R_int	0.075
(sin θ/λ)_max (Å⁻¹)	0.628

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.099, 0.94
No. of reflections	3922
No. of parameters	221
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.51, −0.31

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

The authors are grateful to Xianggao Meng for the data collection.

References

Bruker (1997). SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconsin,USA. Google Scholar
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