(IUCr) Crystallography Journals Online

Abstract top

In the title compound, C₁₂H₁₁FO₄S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment [O-S-C-C and C-S-C-C torsion angles = 126.70 (13) and -123.55 (13)°, respectively]. The crystal structure is stabilized by weak non-classical intermolecular C-HO hydrogen-bond interactions. The crystal structure also exhibits aromatic [pi] - [pi] stacking interactions between furan/benzene and benzene/benzene rings of adjacent benzofuran ring systems [centroid-centroid distances = 3.8258 (9) and 3.8794 (9) Å] and a weak intermolecular C-H [pi] ring interaction.

Comment top

Molecules containing the benzofuran skeleton have received considerable attention related to their pharmacological properties (Howlett et al., 1999; Twyman & Allsop, 1999). This work is related to our communications on the synthesis and crystal structures of methyl 2-(5-halo-3-methylsulfinyl-1-benzofuran-2-yl)acetate derivatives, viz. methyl 2-(5-chloro-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008a), and methyl 2-(5-bromo-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008b). Here we report the crystal structure of the title compound, methyl 2-(5-fluoro-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.006 (1) ° from the least-squares plane defined by the nine constituent atoms (Fig. 1). In the title compound, all of the bond angles and bond distances are in the normal range of related molecules (Choi et al., 2008a, b). The oxygen atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment [O4–S–C1–C8 and C12–S–C1–C8 torsional angles = 126.70 (13)° and -123.55 (13) °, respectively]. Crystal packing is stabilized by weak intermolecular C–H···O hydrogen bond interactions involving the S═O unit with the benzofurn ring (C3–H3···O4ⁱ) and a methylene H atom (C9–H9A···O4ⁱⁱ), between the furan ring and methylene H atom (C9–H9B···O1ⁱⁱⁱ) as well as between a methyl H atom of the methylsulfinyl substituent and the C═O unit (C12–H12A···O3^iv), respectively (Fig. 2, Table 1). Crystal packing also exhibits aromatic π–π stacking interactions between the furan/benzene and the benzene/benzene rings of neighbouring molecules [Cg1···Cg2^vii = 3.8258 (9)Å and Cg2···Cg2^vi = 3.8794 (9)Å, where Cg1 and Cg2 are centroids of the furan (C1/C2/C7/O1/C8) and benzene (C2-C7) rings, respectively, Fig. 3]. The molecular packing is further stabilized by a weak, intermolecular C–H···π ring interaction between a methyl H atom of the methoxy group and a benzene ring of a neighbouring molecule (C11–H11A···Cg2^v; = 3.927 (3)Å, Table 1).

Methyl 2-(5-fluoro-3-methylsulfinyl-1-benzofuran-2-yl)acetate top

Crystal data top

C₁₂H₁₁FO₄S	Z = 2
M_r = 270.27	F(000) = 280
Triclinic, P1	D_x = 1.442 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.7799 (5) Å	Cell parameters from 3896 reflections
b = 8.5609 (6) Å	θ = 2.7–27.5°
c = 10.5592 (7) Å	µ = 0.28 mm⁻¹
α = 73.834 (1)°	T = 273 K
β = 80.178 (1)°	Block, colorless
γ = 67.486 (1)°	0.60 × 0.40 × 0.40 mm
V = 622.36 (7) Å³

Data collection top

Bruker SMART CCD diffractometer	2389 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.014
graphite	θ_max = 27.0°, θ_min = 2.0°
Detector resolution: 10.0 pixels mm^-1	h = −9→9
φ and ω scans	k = −10→10
5368 measured reflections	l = −13→13
2667 independent 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)] = 0.032	Hydrogen site location: difference Fourier map
wR(F²) = 0.089	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0432P)² + 0.227P] where P = (F_o² + 2F_c²)/3
2667 reflections	(Δ/σ)_max = 0.001
165 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.31 e Å⁻³

Crystal data top

C₁₂H₁₁FO₄S	γ = 67.486 (1)°
M_r = 270.27	V = 622.36 (7) Å³
Triclinic, P1	Z = 2
a = 7.7799 (5) Å	Mo Kα radiation
b = 8.5609 (6) Å	µ = 0.28 mm⁻¹
c = 10.5592 (7) Å	T = 273 K
α = 73.834 (1)°	0.60 × 0.40 × 0.40 mm
β = 80.178 (1)°

Data collection top

Bruker SMART CCD diffractometer	2389 reflections with I > 2σ(I)
5368 measured reflections	R_int = 0.014
2667 independent reflections	θ_max = 27.0°

Refinement top

R[F² > 2σ(F²)] = 0.032	H-atom parameters constrained
wR(F²) = 0.089	Δρ_max = 0.28 e Å⁻³
S = 1.08	Δρ_min = −0.31 e Å⁻³
2667 reflections	Absolute structure: ?
165 parameters	Flack parameter: ?
0 restraints	Rogers parameter: ?

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 > 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.

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 > 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
S	0.73212 (5)	0.63256 (5)	0.04928 (3)	0.03039 (12)
F	0.30035 (14)	0.21264 (13)	0.37311 (11)	0.0513 (3)
O1	0.84250 (14)	0.43881 (13)	0.42317 (9)	0.0288 (2)
O2	1.04499 (16)	0.88742 (15)	0.21928 (13)	0.0436 (3)
O3	0.75373 (16)	0.90527 (15)	0.20563 (13)	0.0449 (3)
O4	0.75098 (17)	0.49556 (16)	−0.02040 (11)	0.0415 (3)
C1	0.73869 (19)	0.53270 (18)	0.21918 (13)	0.0263 (3)
C2	0.63718 (19)	0.42498 (17)	0.29942 (13)	0.0261 (3)
C3	0.4978 (2)	0.37061 (19)	0.27953 (15)	0.0309 (3)
H3	0.4480	0.4036	0.1981	0.037*
C4	0.4390 (2)	0.26551 (19)	0.38775 (17)	0.0352 (3)
C5	0.5098 (2)	0.2096 (2)	0.51151 (16)	0.0375 (4)
H5	0.4641	0.1377	0.5804	0.045*
C6	0.6489 (2)	0.26217 (19)	0.53113 (15)	0.0342 (3)
H6	0.7000	0.2268	0.6124	0.041*
C7	0.70799 (19)	0.36995 (18)	0.42381 (14)	0.0275 (3)
C8	0.85804 (19)	0.53640 (18)	0.29708 (13)	0.0264 (3)
C9	0.9967 (2)	0.62392 (19)	0.27115 (14)	0.0290 (3)
H9A	1.0886	0.5816	0.2024	0.035*
H9B	1.0611	0.5919	0.3506	0.035*
C10	0.9129 (2)	0.82024 (19)	0.22925 (14)	0.0296 (3)
C11	0.9865 (3)	1.0754 (2)	0.1780 (3)	0.0657 (6)
H11A	0.9333	1.1147	0.0941	0.099*
H11B	1.0924	1.1099	0.1701	0.099*
H11C	0.8950	1.1261	0.2425	0.099*
C12	0.4904 (2)	0.7705 (2)	0.04906 (17)	0.0386 (4)
H12A	0.4625	0.8393	−0.0388	0.058*
H12B	0.4656	0.8458	0.1077	0.058*
H12C	0.4139	0.7000	0.0782	0.058*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S	0.0313 (2)	0.0392 (2)	0.02016 (18)	−0.01352 (15)	−0.00616 (13)	−0.00224 (14)
F	0.0428 (6)	0.0440 (6)	0.0702 (7)	−0.0247 (5)	−0.0127 (5)	0.0003 (5)
O1	0.0340 (5)	0.0313 (5)	0.0211 (5)	−0.0111 (4)	−0.0076 (4)	−0.0034 (4)
O2	0.0324 (6)	0.0323 (6)	0.0661 (8)	−0.0123 (5)	−0.0036 (5)	−0.0104 (5)
O3	0.0323 (6)	0.0356 (6)	0.0588 (8)	−0.0086 (5)	−0.0120 (5)	0.0019 (5)
O4	0.0454 (7)	0.0528 (7)	0.0277 (6)	−0.0129 (5)	−0.0069 (5)	−0.0154 (5)
C1	0.0278 (7)	0.0284 (7)	0.0209 (6)	−0.0074 (5)	−0.0053 (5)	−0.0046 (5)
C2	0.0270 (7)	0.0249 (6)	0.0237 (6)	−0.0050 (5)	−0.0036 (5)	−0.0065 (5)
C3	0.0294 (7)	0.0285 (7)	0.0334 (7)	−0.0070 (6)	−0.0071 (6)	−0.0069 (6)
C4	0.0295 (7)	0.0278 (7)	0.0477 (9)	−0.0100 (6)	−0.0051 (6)	−0.0065 (6)
C5	0.0389 (8)	0.0275 (7)	0.0382 (8)	−0.0103 (6)	0.0018 (6)	0.0000 (6)
C6	0.0403 (8)	0.0299 (7)	0.0261 (7)	−0.0082 (6)	−0.0043 (6)	−0.0017 (6)
C7	0.0283 (7)	0.0267 (7)	0.0261 (7)	−0.0065 (5)	−0.0045 (5)	−0.0070 (5)
C8	0.0276 (7)	0.0264 (7)	0.0217 (6)	−0.0055 (5)	−0.0048 (5)	−0.0041 (5)
C9	0.0265 (7)	0.0315 (7)	0.0285 (7)	−0.0078 (6)	−0.0080 (5)	−0.0061 (5)
C10	0.0302 (7)	0.0338 (7)	0.0238 (7)	−0.0112 (6)	−0.0019 (5)	−0.0055 (5)
C11	0.0528 (12)	0.0333 (9)	0.1083 (19)	−0.0182 (9)	−0.0025 (12)	−0.0103 (10)
C12	0.0349 (8)	0.0362 (8)	0.0382 (8)	−0.0074 (6)	−0.0134 (6)	0.0001 (6)

Geometric parameters (Å, °) top

S—O4	1.500 (2)	C4—C5	1.391 (2)
S—C1	1.760 (1)	C5—C6	1.385 (2)
S—C12	1.797 (2)	C5—H5	0.9300
F—C4	1.365 (2)	C6—C7	1.383 (2)
O1—C8	1.374 (2)	C6—H6	0.9300
O1—C7	1.382 (2)	C8—C9	1.484 (2)
O2—C10	1.335 (2)	C9—C10	1.514 (2)
O2—C11	1.450 (2)	C9—H9A	0.9700
O3—C10	1.200 (2)	C9—H9B	0.9700
C1—C8	1.355 (2)	C11—H11A	0.9600
C1—C2	1.444 (2)	C11—H11B	0.9600
C2—C7	1.398 (2)	C11—H11C	0.9600
C2—C3	1.398 (2)	C12—H12A	0.9600
C3—C4	1.374 (2)	C12—H12B	0.9600
C3—H3	0.9300	C12—H12C	0.9600

O4—S—C1	106.58 (7)	C6—C7—C2	123.8 (1)
O4—S—C12	106.22 (8)	C1—C8—O1	111.2 (1)
C1—S—C12	98.29 (7)	C1—C8—C9	132.4 (1)
C8—O1—C7	106.3 (1)	O1—C8—C9	116.5 (1)
C10—O2—C11	116.0 (1)	C8—C9—C10	114.0 (1)
C8—C1—C2	107.3 (1)	C8—C9—H9A	108.8
C8—C1—S	123.2 (1)	C10—C9—H9A	108.8
C2—C1—S	129.4 (1)	C8—C9—H9B	108.8
C7—C2—C3	119.5 (1)	C10—C9—H9B	108.8
C7—C2—C1	104.8 (1)	H9A—C9—H9B	107.7
C3—C2—C1	135.8 (1)	O3—C10—O2	124.1 (1)
C4—C3—C2	115.9 (1)	O3—C10—C9	126.4 (1)
C4—C3—H3	122.1	O2—C10—C9	109.5 (1)
C2—C3—H3	122.1	O2—C11—H11A	109.5
F—C4—C3	117.7 (1)	O2—C11—H11B	109.5
F—C4—C5	117.5 (1)	H11A—C11—H11B	109.5
C3—C4—C5	124.8 (2)	O2—C11—H11C	109.5
C6—C5—C4	119.4 (1)	H11A—C11—H11C	109.5
C6—C5—H5	120.3	H11B—C11—H11C	109.5
C4—C5—H5	120.3	S—C12—H12A	109.5
C7—C6—C5	116.6 (1)	S—C12—H12B	109.5
C7—C6—H6	121.7	H12A—C12—H12B	109.5
C5—C6—H6	121.7	S—C12—H12C	109.5
O1—C7—C6	125.7 (1)	H12A—C12—H12C	109.5
O1—C7—C2	110.5 (1)	H12B—C12—H12C	109.5

O4—S—C1—C8	126.70 (13)	C5—C6—C7—C2	−0.8 (2)
C12—S—C1—C8	−123.55 (13)	C3—C2—C7—O1	−179.47 (12)
O4—S—C1—C2	−48.22 (14)	C1—C2—C7—O1	0.62 (15)
C12—S—C1—C2	61.53 (14)	C3—C2—C7—C6	0.3 (2)
C8—C1—C2—C7	−0.35 (15)	C1—C2—C7—C6	−179.62 (13)
S—C1—C2—C7	175.19 (11)	C2—C1—C8—O1	−0.04 (16)
C8—C1—C2—C3	179.77 (15)	S—C1—C8—O1	−175.92 (9)
S—C1—C2—C3	−4.7 (2)	C2—C1—C8—C9	−179.96 (14)
C7—C2—C3—C4	0.6 (2)	S—C1—C8—C9	4.2 (2)
C1—C2—C3—C4	−179.54 (15)	C7—O1—C8—C1	0.42 (15)
C2—C3—C4—F	178.65 (12)	C7—O1—C8—C9	−179.65 (12)
C2—C3—C4—C5	−1.0 (2)	C1—C8—C9—C10	61.1 (2)
F—C4—C5—C6	−179.15 (14)	O1—C8—C9—C10	−118.82 (13)
C3—C4—C5—C6	0.5 (2)	C11—O2—C10—O3	0.5 (2)
C4—C5—C6—C7	0.4 (2)	C11—O2—C10—C9	179.20 (16)
C8—O1—C7—C6	179.59 (14)	C8—C9—C10—O3	−6.6 (2)
C8—O1—C7—C2	−0.65 (14)	C8—C9—C10—O2	174.75 (12)
C5—C6—C7—O1	178.93 (13)

Hydrogen-bond geometry (Å, °) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O4ⁱ	0.93	2.39	3.303 (2)	166
C9—H9A···O4ⁱⁱ	0.97	2.22	3.179 (2)	168
C9—H9B···O1ⁱⁱⁱ	0.97	2.54	3.489 (2)	166
C12—H12A···O3^iv	0.96	2.60	3.478 (2)	152
C11—H11A···Cg2^v	0.96	2.97	3.93	173

Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x+2, −y+1, −z; (iii) −x+2, −y+1, −z+1; (iv) −x+1, −y+2, −z; (v) x, y+1, z.

Table 1
Hydrogen-bond geometry (Å, °) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O4ⁱ	0.93	2.39	3.303 (2)	166
C9—H9A···O4ⁱⁱ	0.97	2.22	3.179 (2)	168
C9—H9B···O1ⁱⁱⁱ	0.97	2.54	3.489 (2)	166
C12—H12A···O3^iv	0.96	2.60	3.478 (2)	152
C11—H11A···Cg2^v	0.96	2.97	3.93	173

Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x+2, −y+1, −z; (iii) −x+2, −y+1, −z+1; (iv) −x+1, −y+2, −z; (v) x, y+1, z.

supplementary materials

Methyl 2-(5-fluoro-3-methylsulfinyl-1-benzofuran-2-yl)acetate

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

	Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as a small cycles of arbitrary radius.
	Fig. 2. Weak, C–H···O hydrogen bond interactions (dotted lines) in the title compound. [Symmetry code: (i) - x + 1, - y + 1, - z; (ii) - x + 2, - y + 1, - z; (iii) - x + 2, - y + 1, - z + 1; (iv) - x+1, - y + 2, - z.]
	Fig. 3. Weak, π–π stacking and C–H···π ring intermoleclar interactions (dotted lines) in the title compound. Cg1 and C2 denote ring centroids for C1/C2/C7/O1/C8 and C2-C7, respectively.[Symmetry code: (v) x, y + 1, z; (vi) - x + 1, - y + 2 , - z + 1; 1-x, 2-y, (vii) - x + 1, - y + 1, - z + 1.]