5-Bromo-2-(4-fluoro­phen­yl)-7-methyl-3-methyl­sulfinyl-1-benzofuran

Choi, H.D.; Seo, P.J.; Son, B.W.; Lee, U.

doi:10.1107/S160053680905418X

organic compounds

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ISSN: 2056-9890

Volume 66| Part 1| January 2010| Page o215

doi:10.1107/S160053680905418X

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5-Bromo-2-(4-fluorophenyl)-7-methyl-3-methylsulfinyl-1-benzofuran

Hong Dae Choi,^a Pil Ja Seo,^a Byeng Wha Son ^b and Uk Lee ^b ^*

^aDepartment of Chemistry, Dongeui University, San 24 Kaya-dong Busanjin-gu, Busan 614-714, Republic of Korea, and ^bDepartment of Chemistry, Pukyong National University, 599-1 Daeyeon 3-dong, Nam-gu, Busan 608-737, Republic of Korea
^*Correspondence e-mail: uklee@pknu.ac.kr

(Received 15 December 2009; accepted 16 December 2009; online 19 December 2009)

In the title compound, C₁₆H₁₂BrFO₂S, the O atom and the methyl group of the methylsulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment. The 4-fluorophenyl ring is rotated out of the benzofuran plane, as indicated by the dihedral angle of 16.17 (5)°. The crystal structure exhibits an intermolecular C—H⋯O hydrogen bond and a Br⋯O halogen interaction [3.112 (2) Å].

Related literature

For the crystal structures of similar 2-(4-fluorophenyl)-5-halo-3-methylsulfinyl-1-benzofuran derivatives, see: Choi et al. (2009a ,b , 2010 ). For the pharmacological activity of benzofuran compounds, see: Howlett et al. (1999 ); Twyman & Allsop (1999 ). For natural products with benzofuran rings, see: Akgul & Anil (2003 ); Soekamto et al. (2003 ). For a review of halogen interactions, see: Politzer et al. (2007 ).

Experimental

Crystal data

C₁₆H₁₂BrFO₂S
M_r = 367.23
Triclinic, $[P \overline 1]$
a = 7.5313 (6) Å
b = 9.8089 (7) Å
c = 10.9117 (8) Å
α = 106.567 (1)°
β = 92.634 (1)°
γ = 109.526 (1)°
V = 719.23 (9) Å³
Z = 2
Mo Kα radiation
μ = 3.01 mm⁻¹
T = 173 K
0.60 × 0.40 × 0.20 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.586, T_max = 0.746
6248 measured reflections
3083 independent reflections
2802 reflections with I > 2σ(I)
R_int = 0.016

Refinement

R[F² > 2σ(F²)] = 0.023
wR(F²) = 0.060
S = 1.05
3083 reflections
192 parameters
H-atom parameters constrained
Δρ_max = 0.34 e Å⁻³
Δρ_min = −0.39 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C15—H15C⋯O2ⁱ	0.96	2.58	3.294 (2)	131
Symmetry code: (i) x, y+1, z.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); 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 (Farrugia, 1997 ) and DIAMOND (Brandenburg, 1998 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680905418X/kp2245sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680905418X/kp2245Isup2.hkl

checkCIF report

Comment top

Molecules of benzofuran ring skeleton have attracted considerable interest, on account of their pharmacological activity (Howlett et al., 1999; Twyman & Allsop, 1999) and their occurrence as natural products (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our continuing studies on the effect of side chain substituents on the solid state structures of 2-(4-fluorophenyl)-5-halo-3-methylsulfinyl-1-benzofuran analogues (Choi et al., 2009a, b, 2010), we report the crystal structure of the title compound (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.014 (1) Å from the least-squares plane defined by the nine constituent atoms. The dihedral angle formed by the plane of the benzofuran and the 4-fluorophenyl ring is 16.17 (5)°. The crystal packing (Fig. 2) is stabilized by an intermolecular C—H···O hydrogen bond between the methyl H atom and the oxygen of the S═O unit, with a C15—H15C···O2ⁱ (Table 1and Fig. 2). The contact C-Br···O involving the the oxygen atom of the S═O unit [Br···O2ⁱⁱ = 3.112 (1) Å; C—Br···O2ⁱⁱ = 173.44 (7)°] is significantly shorter than the sum of van der Waals radia (3.40 Å) (Politzer et al., 2007).

Related literature top

For the crystal structures of similar 2-(4-fluorophenyl)-5-halo-3-methylsulfinyl-1-benzofuran derivatives, see: Choi et al. (2009a,b, 2010). For the pharmacological activity of benzofuran compounds, see: Howlett et al. (1999); Twyman & Allsop (1999). For natural products with benzofuran rings, see: Akgul & Anil (2003); Soekamto et al. (2003). For a review of halogen interactions, see: Politzer et al. (2007).

Experimental top

77% 3-Chloroperoxybenzoic acid (247 mg, 1.1 mmol) was added in small portions to a stirred solution of 5-bromo-2-(4-fluorophenyl)-7-methyl-3-methylsulfanyl-1-benzofuran (351 mg, 1.0 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 3 h, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated in vacuum. The residue was purified by column chromatography (hexane–ethyl acetate, 1:1 v/v) to afford the title compound as a colourless solid [yield 85%, m.p. 477–478 K; R_f = 0.71 (hexane–ethyl acetate, 1:1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in tetrahydrofuran at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius.
	Fig. 2. C—H···O and C—Br···O interactions (dotted lines) in the crystal structure of the title compound. [Symmetry codes: (i) x, y + 1, z; (ii) - x + 1, - y + 1, - z + 2; (iii) x, y - 1, z .]

5-Bromo-2-(4-fluorophenyl)-7-methyl-3-methylsulfinyl-1-benzofuran top

Crystal data top

C₁₆H₁₂BrFO₂S	Z = 2
M_r = 367.23	F(000) = 368
Triclinic, P1	D_x = 1.696 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.5313 (6) Å	Cell parameters from 4231 reflections
b = 9.8089 (7) Å	θ = 2.3–27.4°
c = 10.9117 (8) Å	µ = 3.01 mm⁻¹
α = 106.567 (1)°	T = 173 K
β = 92.634 (1)°	Block, colourless
γ = 109.526 (1)°	0.60 × 0.40 × 0.20 mm
V = 719.23 (9) Å³

Data collection top

Bruker SMART APEXII CCD diffractometer	3083 independent reflections
Radiation source: Rotating Anode	2802 reflections with I > 2σ(I)
HELIOS monochromator	R_int = 0.016
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.0°, θ_min = 2.0°
ϕ and ω scans	h = −9→9
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −12→12
T_min = 0.586, T_max = 0.746	l = −13→13
6248 measured reflections

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)] = 0.023	Hydrogen site location: difference Fourier map
wR(F²) = 0.060	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0302P)² + 0.3573P] where P = (F_o² + 2F_c²)/3
3083 reflections	(Δ/σ)_max < 0.001
192 parameters	Δρ_max = 0.34 e Å⁻³
0 restraints	Δρ_min = −0.39 e Å⁻³

Crystal data top

C₁₆H₁₂BrFO₂S	γ = 109.526 (1)°
M_r = 367.23	V = 719.23 (9) Å³
Triclinic, P1	Z = 2
a = 7.5313 (6) Å	Mo Kα radiation
b = 9.8089 (7) Å	µ = 3.01 mm⁻¹
c = 10.9117 (8) Å	T = 173 K
α = 106.567 (1)°	0.60 × 0.40 × 0.20 mm
β = 92.634 (1)°

Data collection top

Bruker SMART APEXII CCD diffractometer	3083 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2802 reflections with I > 2σ(I)
T_min = 0.586, T_max = 0.746	R_int = 0.016
6248 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.023	0 restraints
wR(F²) = 0.060	H-atom parameters constrained
S = 1.05	Δρ_max = 0.34 e Å⁻³
3083 reflections	Δρ_min = −0.39 e Å⁻³
192 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Br	0.56892 (3)	0.75819 (2)	1.066631 (17)	0.02668 (7)
S	0.18420 (7)	0.22498 (5)	0.55788 (4)	0.02381 (11)
O1	0.31077 (18)	0.62985 (14)	0.50645 (12)	0.0214 (3)
O2	0.3359 (2)	0.21723 (16)	0.64548 (14)	0.0320 (3)
F	−0.0757 (2)	0.21942 (17)	−0.05951 (11)	0.0476 (4)
C1	0.2455 (3)	0.4180 (2)	0.56565 (17)	0.0207 (4)
C2	0.3406 (3)	0.5483 (2)	0.67945 (17)	0.0197 (3)
C3	0.3970 (3)	0.5713 (2)	0.81000 (17)	0.0217 (4)
H3	0.3726	0.4901	0.8427	0.026*
C4	0.4906 (3)	0.7202 (2)	0.88760 (17)	0.0216 (4)
C5	0.5318 (3)	0.8455 (2)	0.84171 (18)	0.0217 (4)
H5	0.5973	0.9434	0.8985	0.026*
C6	0.4760 (3)	0.8255 (2)	0.71248 (18)	0.0207 (4)
C7	0.3798 (2)	0.6748 (2)	0.63653 (17)	0.0193 (3)
C8	0.2316 (2)	0.4724 (2)	0.46474 (18)	0.0203 (4)
C9	0.1517 (3)	0.4038 (2)	0.32705 (17)	0.0215 (4)
C10	0.0209 (3)	0.2541 (2)	0.27673 (19)	0.0283 (4)
H10	−0.0167	0.1961	0.3316	0.034*
C11	−0.0534 (3)	0.1909 (3)	0.1460 (2)	0.0332 (5)
H11	−0.1376	0.0903	0.1121	0.040*
C12	0.0004 (3)	0.2802 (3)	0.06824 (19)	0.0318 (5)
C13	0.1276 (3)	0.4285 (3)	0.11316 (19)	0.0298 (4)
H13	0.1607	0.4860	0.0575	0.036*
C14	0.2051 (3)	0.4901 (2)	0.24326 (19)	0.0252 (4)
H14	0.2933	0.5895	0.2752	0.030*
C15	0.5111 (3)	0.9548 (2)	0.65832 (19)	0.0268 (4)
H15A	0.5531	0.9286	0.5760	0.040*
H15B	0.6076	1.0448	0.7168	0.040*
H15C	0.3952	0.9737	0.6475	0.040*
C16	−0.0164 (3)	0.2099 (3)	0.6426 (2)	0.0351 (5)
H16A	−0.0639	0.1111	0.6538	0.053*
H16B	−0.1150	0.2230	0.5936	0.053*
H16C	0.0222	0.2874	0.7258	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br	0.03804 (12)	0.02214 (11)	0.01767 (10)	0.01046 (8)	−0.00056 (7)	0.00439 (7)
S	0.0331 (3)	0.0152 (2)	0.0220 (2)	0.00897 (19)	0.00200 (19)	0.00445 (17)
O1	0.0269 (7)	0.0172 (6)	0.0193 (6)	0.0071 (5)	0.0009 (5)	0.0062 (5)
O2	0.0397 (8)	0.0274 (8)	0.0342 (8)	0.0167 (7)	0.0012 (6)	0.0128 (6)
F	0.0504 (8)	0.0559 (9)	0.0194 (6)	0.0055 (7)	−0.0086 (6)	0.0053 (6)
C1	0.0239 (9)	0.0164 (8)	0.0205 (9)	0.0066 (7)	0.0025 (7)	0.0052 (7)
C2	0.0223 (8)	0.0170 (8)	0.0208 (9)	0.0087 (7)	0.0039 (7)	0.0055 (7)
C3	0.0282 (9)	0.0175 (9)	0.0211 (9)	0.0095 (7)	0.0039 (7)	0.0075 (7)
C4	0.0260 (9)	0.0226 (9)	0.0174 (8)	0.0112 (7)	0.0019 (7)	0.0058 (7)
C5	0.0232 (9)	0.0159 (9)	0.0232 (9)	0.0071 (7)	0.0020 (7)	0.0026 (7)
C6	0.0222 (9)	0.0170 (9)	0.0239 (9)	0.0083 (7)	0.0051 (7)	0.0065 (7)
C7	0.0211 (8)	0.0186 (9)	0.0186 (8)	0.0076 (7)	0.0015 (7)	0.0062 (7)
C8	0.0200 (8)	0.0173 (9)	0.0221 (9)	0.0063 (7)	0.0034 (7)	0.0046 (7)
C9	0.0203 (8)	0.0242 (9)	0.0202 (9)	0.0095 (7)	0.0020 (7)	0.0059 (7)
C10	0.0276 (10)	0.0276 (10)	0.0253 (10)	0.0051 (8)	0.0010 (8)	0.0083 (8)
C11	0.0282 (10)	0.0311 (11)	0.0287 (11)	0.0026 (9)	−0.0032 (8)	0.0033 (9)
C12	0.0290 (10)	0.0415 (12)	0.0187 (9)	0.0108 (9)	−0.0018 (8)	0.0037 (9)
C13	0.0310 (10)	0.0368 (12)	0.0233 (10)	0.0117 (9)	0.0031 (8)	0.0130 (9)
C14	0.0259 (9)	0.0247 (10)	0.0242 (9)	0.0093 (8)	0.0022 (8)	0.0070 (8)
C15	0.0364 (11)	0.0192 (9)	0.0261 (10)	0.0102 (8)	0.0063 (8)	0.0087 (8)
C16	0.0333 (11)	0.0280 (11)	0.0443 (13)	0.0068 (9)	0.0101 (10)	0.0164 (10)

Geometric parameters (Å, º) top

Br—C4	1.907 (2)	C6—C15	1.497 (3)
Br—O2ⁱ	3.112 (2)	C8—C9	1.463 (2)
S—O2	1.491 (2)	C9—C10	1.397 (3)
S—C1	1.768 (2)	C9—C14	1.401 (3)
S—C16	1.794 (2)	C10—C11	1.386 (3)
O1—C7	1.379 (2)	C10—H10	0.9300
O1—C8	1.381 (2)	C11—C12	1.368 (3)
F—C12	1.360 (2)	C11—H11	0.9300
C1—C8	1.368 (3)	C12—C13	1.375 (3)
C1—C2	1.445 (2)	C13—C14	1.386 (3)
C2—C7	1.394 (2)	C13—H13	0.9300
C2—C3	1.399 (2)	C14—H14	0.9300
C3—C4	1.378 (3)	C15—H15A	0.9600
C3—H3	0.9300	C15—H15B	0.9600
C4—C5	1.403 (3)	C15—H15C	0.9600
C5—C6	1.391 (3)	C16—H16A	0.9600
C5—H5	0.9300	C16—H16B	0.9600
C6—C7	1.389 (2)	C16—H16C	0.9600

C4—Br—O2ⁱ	173.44 (7)	C10—C9—C8	121.62 (17)
O2—S—C1	107.33 (9)	C14—C9—C8	119.58 (17)
O2—S—C16	105.95 (10)	C11—C10—C9	120.85 (19)
C1—S—C16	97.80 (9)	C11—C10—H10	119.6
C7—O1—C8	106.74 (13)	C9—C10—H10	119.6
C8—C1—C2	107.32 (16)	C12—C11—C10	118.3 (2)
C8—C1—S	127.08 (14)	C12—C11—H11	120.8
C2—C1—S	125.27 (14)	C10—C11—H11	120.8
C7—C2—C3	118.96 (16)	F—C12—C11	118.39 (19)
C7—C2—C1	105.04 (15)	F—C12—C13	118.55 (19)
C3—C2—C1	136.00 (17)	C11—C12—C13	123.06 (19)
C4—C3—C2	116.62 (16)	C12—C13—C14	118.48 (19)
C4—C3—H3	121.7	C12—C13—H13	120.8
C2—C3—H3	121.7	C14—C13—H13	120.8
C3—C4—C5	123.42 (17)	C13—C14—C9	120.46 (18)
C3—C4—Br	118.40 (14)	C13—C14—H14	119.8
C5—C4—Br	118.17 (14)	C9—C14—H14	119.8
C6—C5—C4	120.97 (17)	C6—C15—H15A	109.5
C6—C5—H5	119.5	C6—C15—H15B	109.5
C4—C5—H5	119.5	H15A—C15—H15B	109.5
C7—C6—C5	114.57 (16)	C6—C15—H15C	109.5
C7—C6—C15	121.86 (17)	H15A—C15—H15C	109.5
C5—C6—C15	123.54 (17)	H15B—C15—H15C	109.5
O1—C7—C6	124.01 (16)	S—C16—H16A	109.5
O1—C7—C2	110.54 (15)	S—C16—H16B	109.5
C6—C7—C2	125.44 (17)	H16A—C16—H16B	109.5
C1—C8—O1	110.33 (16)	S—C16—H16C	109.5
C1—C8—C9	135.27 (17)	H16A—C16—H16C	109.5
O1—C8—C9	114.40 (15)	H16B—C16—H16C	109.5
C10—C9—C14	118.79 (17)

O2—S—C1—C8	138.31 (17)	C1—C2—C7—O1	1.57 (19)
C16—S—C1—C8	−112.23 (18)	C3—C2—C7—C6	1.6 (3)
O2—S—C1—C2	−34.18 (18)	C1—C2—C7—C6	−177.92 (17)
C16—S—C1—C2	75.29 (18)	C2—C1—C8—O1	−0.4 (2)
C8—C1—C2—C7	−0.7 (2)	S—C1—C8—O1	−173.93 (13)
S—C1—C2—C7	172.99 (14)	C2—C1—C8—C9	−179.25 (19)
C8—C1—C2—C3	179.9 (2)	S—C1—C8—C9	7.2 (3)
S—C1—C2—C3	−6.4 (3)	C7—O1—C8—C1	1.32 (19)
C7—C2—C3—C4	−0.6 (3)	C7—O1—C8—C9	−179.53 (14)
C1—C2—C3—C4	178.7 (2)	C1—C8—C9—C10	17.4 (3)
C2—C3—C4—C5	−0.7 (3)	O1—C8—C9—C10	−161.47 (17)
C2—C3—C4—Br	179.49 (13)	C1—C8—C9—C14	−163.3 (2)
C3—C4—C5—C6	1.1 (3)	O1—C8—C9—C14	17.8 (2)
Br—C4—C5—C6	−179.08 (14)	C14—C9—C10—C11	0.7 (3)
C4—C5—C6—C7	−0.2 (3)	C8—C9—C10—C11	180.00 (18)
C4—C5—C6—C15	178.35 (17)	C9—C10—C11—C12	−1.8 (3)
C8—O1—C7—C6	177.69 (17)	C10—C11—C12—F	−178.57 (19)
C8—O1—C7—C2	−1.81 (19)	C10—C11—C12—C13	1.4 (3)
C5—C6—C7—O1	179.43 (16)	F—C12—C13—C14	−179.89 (18)
C15—C6—C7—O1	0.9 (3)	C11—C12—C13—C14	0.1 (3)
C5—C6—C7—C2	−1.1 (3)	C12—C13—C14—C9	−1.3 (3)
C15—C6—C7—C2	−179.68 (17)	C10—C9—C14—C13	0.8 (3)
C3—C2—C7—O1	−178.94 (15)	C8—C9—C14—C13	−178.44 (17)

Symmetry code: (i) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15C···O2ⁱⁱ	0.96	2.58	3.294 (2)	131

Symmetry code: (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formula	C₁₆H₁₂BrFO₂S
M_r	367.23
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	7.5313 (6), 9.8089 (7), 10.9117 (8)
α, β, γ (°)	106.567 (1), 92.634 (1), 109.526 (1)
V (Å³)	719.23 (9)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.01
Crystal size (mm)	0.60 × 0.40 × 0.20

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.586, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	6248, 3083, 2802
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.023, 0.060, 1.05
No. of reflections	3083
No. of parameters	192
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.39

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15C···O2ⁱ	0.96	2.58	3.294 (2)	131.4

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

References

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Volume 66| Part 1| January 2010| Page o215

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