3-(4-Fluoro­phenyl­sulfin­yl)-2-methyl-1-benzofuran

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

doi:10.1107/S1600536810004411

organic compounds

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ISSN: 2056-9890

Volume 66| Part 3| March 2010| Page o564

doi:10.1107/S1600536810004411

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3-(4-Fluorophenylsulfinyl)-2-methyl-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 3 February 2010; accepted 4 February 2010; online 10 February 2010)

In the title compound, C₁₅H₁₁FO₂S, the O atom and the 4-fluorophenyl group of the 4-fluorophenylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment; the 4-fluorophenyl ring is almost perpendicular to this plane [dihedral angle = 89.59 (5)°]. Intermolecular C—H⋯F and C—H⋯O hydrogen bonds link the molecules together in the crystal structure.

Related literature

For the crystal structures of similar 2-methyl-3-phenylsulfinyl-1-benzofuran derivatives, see: Choi et al. (2008a ,b ,c ). For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006 ); Galal et al. (2009 ); Khan et al. (2005 ). For natural products with benzofuran rings, see: Akgul & Anil (2003 ); Soekamto et al. (2003 ).

Experimental

Crystal data

C₁₅H₁₁FO₂S
M_r = 274.30
Orthorhombic, P b c n
a = 14.992 (1) Å
b = 10.4661 (8) Å
c = 16.008 (1) Å
V = 2511.8 (3) Å³
Z = 8
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 173 K
0.50 × 0.50 × 0.25 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.880, T_max = 0.937
14681 measured reflections
2878 independent reflections
2315 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.101
S = 1.10
2878 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯Fⁱ	0.93	2.52	3.346 (2)	148
C9—H9B⋯O2ⁱⁱ	0.96	2.41	3.189 (2)	138
Symmetry codes: (i) $[-x+1, y+1, -z+{\script{1\over 2}}]$ ; (ii) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z]$ .

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 datablock I. DOI: 10.1107/S1600536810004411/bg2329sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810004411/bg2329Isup2.hkl

checkCIF report

Comment top

Molecules containing benzofuran skeleton show significant pharmacological activities such as antifungal (Aslam et al., 2006), antitumor and antiviral (Galal et al., 2009), antimicrobial (Khan et al., 2005) properties. These compounds are widely occurring in nature (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing studies of the effect of side chain substituents on the solid state structures of 2-methyl-3-phenylsulfinyl-1-benzofuran analogues (Choi et al., 2008a,b,c), we report the crystal structure of the title compound (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.012 (1) Å from the least-squares plane defined by the nine constituent atoms. The 4-fluorophenyl ring is almost perpendicular to the plane of the benzofuran fragment [89.59 (5)°] and is tilted slightly towards it. The crystal packing (Fig. 2) is stabilized by two different intermolecular hydrogen bonds; the first one a C—H···F contact between the benzene H atom and the fluorine (Table 1, first entry ), and the second, a C—H···O one between one methyl H atom and the oxygen of the S═O unit (Table 1, second entry).

Related literature top

For the crystal structures of similar 2-methyl-3-phenylsulfinyl-1-benzofuran derivatives, see: Choi et al. (2008a,b,c). For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006); Galal et al. (2009); Khan et al. (2005). For natural products with benzofuran rings, see: Akgul & Anil (2003); Soekamto et al. (2003).

Experimental top

77% 3-Chloroperoxybenzoic acid (359 mg, 1.6 mmol) was added in small portions to a stirred solution of 3-(4-fluorophenylsulfanyl)-2-methyl-1-benzofuran (387 mg, 1.5 mmol) in dichloromethane (40 mL) at 273 K. After being stirred at room temperature for 4h, 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 colorless solid [yield 78%, m.p. 415–416 K; R_f = 0.63 (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 benzene 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···F and C—H···O interactions (dotted lines) in the crystal structure of the title compound. [Symmetry codes: i) - x + 1, y + 1, - z + 1/2; ii) - x + 3/2, y + 1/2, z; iii) - x + 3/2, y - 1/2, z; iv) - x + 1, y - 1, - z + 1/2.]

3-(4-Fluorophenylsulfinyl)-2-methyl-1-benzofuran top

Crystal data top

C₁₅H₁₁FO₂S	F(000) = 1136
M_r = 274.30	D_x = 1.451 Mg m⁻³
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2ab	Cell parameters from 6779 reflections
a = 14.992 (1) Å	θ = 2.4–27.5°
b = 10.4661 (8) Å	µ = 0.26 mm⁻¹
c = 16.008 (1) Å	T = 173 K
V = 2511.8 (3) Å³	Block, colourless
Z = 8	0.50 × 0.50 × 0.25 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	2878 independent reflections
Radiation source: Rotating Anode	2315 reflections with I > 2σ(I)
Bruker HELIOS graded multilayer optics monochromator	R_int = 0.026
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.5°, θ_min = 2.4°
ϕ and ω scans	h = −18→19
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −13→13
T_min = 0.880, T_max = 0.937	l = −15→20
14681 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)] = 0.035	Hydrogen site location: difference Fourier map
wR(F²) = 0.101	H-atom parameters constrained
S = 1.10	w = 1/[σ²(F_o²) + (0.0443P)² + 1.1695P] where P = (F_o² + 2F_c²)/3
2878 reflections	(Δ/σ)_max < 0.001
173 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₁₅H₁₁FO₂S	V = 2511.8 (3) Å³
M_r = 274.30	Z = 8
Orthorhombic, Pbcn	Mo Kα radiation
a = 14.992 (1) Å	µ = 0.26 mm⁻¹
b = 10.4661 (8) Å	T = 173 K
c = 16.008 (1) Å	0.50 × 0.50 × 0.25 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	2878 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2315 reflections with I > 2σ(I)
T_min = 0.880, T_max = 0.937	R_int = 0.026
14681 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.101	H-atom parameters constrained
S = 1.10	Δρ_max = 0.29 e Å⁻³
2878 reflections	Δρ_min = −0.32 e Å⁻³
173 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
S	0.65767 (3)	0.58401 (4)	0.06490 (3)	0.03017 (13)
F	0.44627 (8)	0.14149 (11)	0.17017 (8)	0.0492 (3)
O1	0.59892 (8)	0.88631 (11)	0.19868 (8)	0.0342 (3)
O2	0.75317 (9)	0.54319 (13)	0.06877 (8)	0.0394 (3)
C1	0.63870 (11)	0.69730 (16)	0.14353 (10)	0.0276 (3)
C2	0.66131 (10)	0.69382 (15)	0.23170 (10)	0.0265 (3)
C3	0.70180 (11)	0.60712 (17)	0.28570 (11)	0.0310 (4)
H3	0.7212	0.5278	0.2668	0.037*
C4	0.71236 (12)	0.64306 (18)	0.36876 (11)	0.0352 (4)
H4	0.7384	0.5862	0.4062	0.042*
C5	0.68456 (13)	0.76314 (19)	0.39714 (11)	0.0374 (4)
H5	0.6926	0.7844	0.4531	0.045*
C6	0.64547 (12)	0.85086 (18)	0.34404 (11)	0.0362 (4)
H6	0.6272	0.9310	0.3625	0.043*
C7	0.63504 (11)	0.81283 (16)	0.26195 (11)	0.0299 (4)
C8	0.60331 (11)	0.81418 (16)	0.12734 (11)	0.0306 (4)
C9	0.57041 (13)	0.87542 (19)	0.04971 (12)	0.0399 (4)
H9A	0.5808	0.8195	0.0032	0.060*
H9B	0.6015	0.9545	0.0410	0.060*
H9C	0.5076	0.8919	0.0547	0.060*
C10	0.59373 (11)	0.45389 (15)	0.10668 (10)	0.0274 (3)
C11	0.63578 (12)	0.33736 (17)	0.11793 (11)	0.0316 (4)
H11	0.6971	0.3304	0.1102	0.038*
C12	0.58623 (13)	0.23096 (17)	0.14081 (11)	0.0360 (4)
H12	0.6134	0.1521	0.1493	0.043*
C13	0.49582 (12)	0.24576 (16)	0.15059 (11)	0.0341 (4)
C14	0.45240 (12)	0.36075 (18)	0.14095 (11)	0.0359 (4)
H14	0.3912	0.3671	0.1494	0.043*
C15	0.50226 (12)	0.46665 (16)	0.11837 (11)	0.0329 (4)
H15	0.4748	0.5456	0.1111	0.040*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S	0.0341 (2)	0.0313 (2)	0.0251 (2)	−0.00272 (17)	−0.00071 (16)	−0.00052 (16)
F	0.0562 (7)	0.0355 (6)	0.0558 (7)	−0.0171 (5)	−0.0002 (6)	0.0001 (5)
O1	0.0408 (7)	0.0264 (6)	0.0354 (6)	0.0025 (5)	−0.0010 (5)	0.0017 (5)
O2	0.0311 (6)	0.0435 (7)	0.0437 (7)	−0.0024 (5)	0.0071 (6)	−0.0052 (6)
C1	0.0280 (8)	0.0273 (8)	0.0276 (8)	−0.0023 (6)	−0.0021 (6)	0.0010 (6)
C2	0.0253 (8)	0.0270 (8)	0.0273 (8)	−0.0037 (6)	0.0007 (6)	0.0000 (6)
C3	0.0317 (9)	0.0301 (8)	0.0311 (9)	0.0002 (7)	−0.0003 (7)	0.0017 (7)
C4	0.0347 (9)	0.0397 (10)	0.0312 (9)	−0.0023 (7)	−0.0049 (7)	0.0057 (7)
C5	0.0409 (10)	0.0442 (10)	0.0270 (9)	−0.0082 (8)	−0.0001 (8)	−0.0041 (8)
C6	0.0422 (10)	0.0307 (9)	0.0357 (9)	−0.0039 (7)	0.0052 (8)	−0.0053 (7)
C7	0.0310 (9)	0.0266 (8)	0.0320 (9)	−0.0026 (6)	0.0005 (7)	0.0024 (7)
C8	0.0287 (8)	0.0294 (8)	0.0337 (9)	−0.0033 (7)	−0.0028 (7)	0.0019 (7)
C9	0.0414 (10)	0.0371 (10)	0.0412 (10)	0.0005 (8)	−0.0091 (8)	0.0097 (8)
C10	0.0311 (8)	0.0274 (8)	0.0236 (8)	−0.0021 (6)	−0.0033 (6)	−0.0037 (6)
C11	0.0306 (9)	0.0320 (9)	0.0324 (9)	0.0038 (7)	−0.0009 (7)	−0.0045 (7)
C12	0.0453 (10)	0.0265 (8)	0.0364 (9)	0.0037 (7)	−0.0036 (8)	−0.0042 (7)
C13	0.0422 (10)	0.0287 (8)	0.0314 (9)	−0.0099 (7)	−0.0028 (7)	−0.0040 (7)
C14	0.0276 (8)	0.0398 (10)	0.0402 (10)	−0.0024 (7)	−0.0023 (7)	−0.0042 (8)
C15	0.0304 (8)	0.0291 (9)	0.0393 (9)	0.0028 (7)	−0.0049 (7)	−0.0010 (7)

Geometric parameters (Å, º) top

S—O2	1.4953 (14)	C6—C7	1.382 (2)
S—C1	1.7525 (17)	C6—H6	0.9300
S—C10	1.7948 (17)	C8—C9	1.483 (2)
F—C13	1.357 (2)	C9—H9A	0.9600
O1—C8	1.371 (2)	C9—H9B	0.9600
O1—C7	1.382 (2)	C9—H9C	0.9600
C1—C8	1.358 (2)	C10—C11	1.385 (2)
C1—C2	1.452 (2)	C10—C15	1.390 (2)
C2—C3	1.393 (2)	C11—C12	1.388 (3)
C2—C7	1.393 (2)	C11—H11	0.9300
C3—C4	1.391 (2)	C12—C13	1.373 (3)
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.400 (3)	C13—C14	1.377 (3)
C4—H4	0.9300	C14—C15	1.385 (3)
C5—C6	1.382 (3)	C14—H14	0.9300
C5—H5	0.9300	C15—H15	0.9300

O2—S—C1	108.60 (8)	C1—C8—C9	132.78 (17)
O2—S—C10	106.21 (8)	O1—C8—C9	116.38 (15)
C1—S—C10	99.15 (8)	C8—C9—H9A	109.5
C8—O1—C7	106.58 (13)	C8—C9—H9B	109.5
C8—C1—C2	107.42 (15)	H9A—C9—H9B	109.5
C8—C1—S	122.38 (13)	C8—C9—H9C	109.5
C2—C1—S	130.04 (13)	H9A—C9—H9C	109.5
C3—C2—C7	119.34 (15)	H9B—C9—H9C	109.5
C3—C2—C1	136.18 (16)	C11—C10—C15	121.07 (16)
C7—C2—C1	104.45 (14)	C11—C10—S	118.27 (13)
C4—C3—C2	117.83 (16)	C15—C10—S	120.27 (13)
C4—C3—H3	121.1	C10—C11—C12	119.83 (16)
C2—C3—H3	121.1	C10—C11—H11	120.1
C3—C4—C5	121.28 (17)	C12—C11—H11	120.1
C3—C4—H4	119.4	C13—C12—C11	117.90 (16)
C5—C4—H4	119.4	C13—C12—H12	121.1
C6—C5—C4	121.55 (17)	C11—C12—H12	121.1
C6—C5—H5	119.2	F—C13—C12	118.42 (16)
C4—C5—H5	119.2	F—C13—C14	118.04 (16)
C5—C6—C7	116.21 (17)	C12—C13—C14	123.54 (16)
C5—C6—H6	121.9	C13—C14—C15	118.26 (16)
C7—C6—H6	121.9	C13—C14—H14	120.9
C6—C7—O1	125.51 (16)	C15—C14—H14	120.9
C6—C7—C2	123.78 (16)	C14—C15—C10	119.38 (16)
O1—C7—C2	110.70 (14)	C14—C15—H15	120.3
C1—C8—O1	110.84 (15)	C10—C15—H15	120.3

O2—S—C1—C8	125.82 (15)	C2—C1—C8—O1	−1.56 (19)
C10—S—C1—C8	−123.54 (15)	S—C1—C8—O1	−177.39 (11)
O2—S—C1—C2	−48.99 (17)	C2—C1—C8—C9	178.10 (18)
C10—S—C1—C2	61.65 (16)	S—C1—C8—C9	2.3 (3)
C8—C1—C2—C3	−176.81 (19)	C7—O1—C8—C1	1.47 (18)
S—C1—C2—C3	−1.4 (3)	C7—O1—C8—C9	−178.25 (15)
C8—C1—C2—C7	1.00 (18)	O2—S—C10—C11	−12.66 (15)
S—C1—C2—C7	176.41 (13)	C1—S—C10—C11	−125.19 (13)
C7—C2—C3—C4	1.4 (2)	O2—S—C10—C15	174.41 (13)
C1—C2—C3—C4	178.99 (18)	C1—S—C10—C15	61.88 (15)
C2—C3—C4—C5	−1.0 (3)	C15—C10—C11—C12	0.3 (3)
C3—C4—C5—C6	0.1 (3)	S—C10—C11—C12	−172.52 (13)
C4—C5—C6—C7	0.4 (3)	C10—C11—C12—C13	0.7 (3)
C5—C6—C7—O1	−178.95 (16)	C11—C12—C13—F	177.80 (15)
C5—C6—C7—C2	0.1 (3)	C11—C12—C13—C14	−1.7 (3)
C8—O1—C7—C6	178.34 (17)	F—C13—C14—C15	−177.99 (15)
C8—O1—C7—C2	−0.79 (18)	C12—C13—C14—C15	1.5 (3)
C3—C2—C7—C6	−1.0 (3)	C13—C14—C15—C10	−0.3 (3)
C1—C2—C7—C6	−179.27 (16)	C11—C10—C15—C14	−0.6 (3)
C3—C2—C7—O1	178.14 (14)	S—C10—C15—C14	172.18 (13)
C1—C2—C7—O1	−0.12 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···Fⁱ	0.93	2.52	3.346 (2)	148
C9—H9B···O2ⁱⁱ	0.96	2.41	3.189 (2)	138

Symmetry codes: (i) −x+1, y+1, −z+1/2; (ii) −x+3/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₁FO₂S
M_r	274.30
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	173
a, b, c (Å)	14.992 (1), 10.4661 (8), 16.008 (1)
V (Å³)	2511.8 (3)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.50 × 0.50 × 0.25

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.880, 0.937
No. of measured, independent and observed [I > 2σ(I)] reflections	14681, 2878, 2315
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.101, 1.10
No. of reflections	2878
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.32

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
C6—H6···Fⁱ	0.93	2.52	3.346 (2)	148.4
C9—H9B···O2ⁱⁱ	0.96	2.41	3.189 (2)	138.1

Symmetry codes: (i) −x+1, y+1, −z+1/2; (ii) −x+3/2, y+1/2, z.

References

Akgul, Y. Y. & Anil, H. (2003). Phytochemistry, 63, 939–943. Web of Science CrossRef PubMed CAS Google Scholar
Aslam, S. N., Stevenson, P. C., Phythian, S. J., Veitch, N. C. & Hall, D. R. (2006). Tetrahedron, 62, 4214–4226. Web of Science CrossRef CAS Google Scholar
Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2009). SADABS. APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
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Volume 66| Part 3| March 2010| Page o564

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