Crystal structure of 2,5-dimethyl-3-(2-methyl­phenyl­sulfin­yl)-1-benzo­furan

Choi, H.D.; Lee, U.

doi:10.1107/S2056989015012773

organic compounds

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ISSN: 2056-9890

Volume 71| Part 8| August 2015| Pages o554-o555

https://doi.org/10.1107/S2056989015012773

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Crystal structure of 2,5-dimethyl-3-(2-methylphenylsulfinyl)-1-benzofuran

Hong Dae Choi ^a 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

Edited by V. V. Chernyshev, Moscow State University, Russia (Received 30 June 2015; accepted 2 July 2015; online 8 July 2015)

In the title compound, C₁₇H₁₆O₂S, the dihedral angle between the benzofuran ring system [r.m.s. deviation = 0.009 (1) Å] and the 2-methylphenyl ring is 86.72 (4)°. In the crystal, weak C—H⋯O hydrogen bonds link the molecules into columns along the b-axis direction.

Keywords: crystal structure; benzofuran; 2-methylphenyl; C—H⋯O hydrogen bonds.

CCDC reference: 1410058

1. Related literature

For the pharmacological properties of benzofuran compounds, see: Aslam et al. (2009 ); Galal et al. (2009 ); Howlett et al. (1999 ); Wahab Khan et al. (2005 ); Ono et al. (2002 ). For natural products with a benzofuran ring, see: Akgul & Anil (2003 ); Soekamto et al. (2003 ). For a related structure, see: Choi et al. (2012 ). For further synthetic details, see: Choi et al. (1999 ).

2. Experimental

2.1. Crystal data

C₁₇H₁₆O₂S
M_r = 284.36
Monoclinic, P 2₁ /n
a = 10.8458 (2) Å
b = 8.0139 (1) Å
c = 16.4295 (2) Å
β = 96.709 (1)°
V = 1418.23 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 173 K
0.44 × 0.33 × 0.30 mm

2.2. Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.692, T_max = 0.746
25176 measured reflections
3529 independent reflections
3091 reflections with I > 2σ(I)
R_int = 0.033

2.3. Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.103
S = 1.05
3529 reflections
184 parameters
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O2ⁱ	0.95	2.45	3.3772 (18)	166
C17—H17B⋯O2ⁱⁱ	0.98	2.55	3.458 (2)	154
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) x, y-1, z.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and DIAMOND (Brandenburg, 1998 ); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2008).

Supporting information

CCDC reference: 1410058

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015012773/cv5492sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015012773/cv5492Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015012773/cv5492Isup3.cml

checkCIF report

Comment top

Benzofuran derivatives show interesting pharmacological properties such as antibacterial and antifungal, antitumor and antiviral, antimicrobial activities (Aslam et al. 2009; Galal et al., 2009; Wahab Khan et al., 2005), and potential inhibitor of β-amyloid aggregation (Howlett et al., 1999; Ono et al., 2002). These benzofuran compounds occur in a great number of natural products. (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our continuing project on benzofuran derivatives (Choi et al., 2012), we report herein on the crystal structure of the title compound.

In the title molecule (Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.009 (1) Å from the least-squares plane defined by the nine constituent atoms. The 2-methylphenyl ring is essentially planar, with a mean deviation of 0.004 (1) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring and the 2-methylphenyl ring is 86.72 (4)°. In the crystal, molecules are linked into a chain along the b axis direction by C—H···O hydrogen bonds (Table 1 and Fig. 2). These molecules are connected on either side of this chain by further C—H···O hydrogen bonds (Table 1 and Fig. 2).

Related literature top

For the pharmacological properties of benzofuran compounds, see: Aslam et al. (2009); Galal et al. (2009); Howlett et al. (1999); Wahab Khan et al. (2005); Ono et al. (2002). For natural products with a benzofuran ring, see: Akgul & Anil (2003); Soekamto et al. (2003). For a related structure, see: Choi et al. (2012). For further synthetic details, see: Choi et al. (1999).

Experimental top

The starting material 2,5-dimethyl-3-(2-methylphenylsulfanyl)-1-benzofuran was prepared by literature method (Choi et al. 1999). 3-Chloroperoxybenzoic acid (77%, 224 mg, 1.0 mmol) was added in small portions to a stirred solution of 2,5-dimethyl-3-(2-methylphenylsulfanyl)-1-benzofuran (241 mg, 0.9 mmol) in dichloromethane (25 ml) at 273 K. After being stirred at room temperature for 8h, the mixture was washed with saturated sodium bicarbonate solution (2 X 10 ml) and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by column chromatography (hexane–ethyl acetate, 2:1 v/v) to afford the title compound as a colorless solid [yield 68% (174 mg); m.p. 415–416 K; R_f = 0.49 (hexane–ethyl acetate, 2:1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound (21 mg) in ethyl acetate (20 ml) at room temperature.

Structure description top

For the pharmacological properties of benzofuran compounds, see: Aslam et al. (2009); Galal et al. (2009); Howlett et al. (1999); Wahab Khan et al. (2005); Ono et al. (2002). For natural products with a benzofuran ring, see: Akgul & Anil (2003); Soekamto et al. (2003). For a related structure, see: Choi et al. (2012). For further synthetic details, see: Choi et al. (1999).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as small spheres of arbitrary radius.
	Fig. 2. A view of the C—H···O hydrogen bonds (dotted lines) in the crystal structure of the title compound. H atoms non-participating in hydrogen-bonding were omitted for clarity. [Symmetry codes: (i) - x + 1/2, y - 1/2 , - z + 3/2; (ii) x, y - 1, z; (iii) - x + 1/2, y + 1/2 , - z + 3/2; (iv) x, y + 1, z.]

2,5-Dimethyl-3-(2-methylphenylsulfinyl)-1-benzofuran top

Crystal data top

C₁₇H₁₆O₂S	F(000) = 600
M_r = 284.36	D_x = 1.332 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 10.8458 (2) Å	Cell parameters from 9125 reflections
b = 8.0139 (1) Å	θ = 2.5–28.1°
c = 16.4295 (2) Å	µ = 0.23 mm⁻¹
β = 96.709 (1)°	T = 173 K
V = 1418.23 (4) Å³	Block, colourless
Z = 4	0.44 × 0.33 × 0.30 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	3529 independent reflections
Radiation source: rotating anode	3091 reflections with I > 2σ(I)
Graphite multilayer monochromator	R_int = 0.033
Detector resolution: 10.0 pixels mm^-1	θ_max = 28.4°, θ_min = 2.1°
φ and ω scans	h = −14→14
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −10→10
T_min = 0.692, T_max = 0.746	l = −21→20
25176 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)] = 0.037	Hydrogen site location: difference Fourier map
wR(F²) = 0.103	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0515P)² + 0.5244P] where P = (F_o² + 2F_c²)/3
3529 reflections	(Δ/σ)_max = 0.001
184 parameters	Δρ_max = 0.30 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₁₇H₁₆O₂S	V = 1418.23 (4) Å³
M_r = 284.36	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.8458 (2) Å	µ = 0.23 mm⁻¹
b = 8.0139 (1) Å	T = 173 K
c = 16.4295 (2) Å	0.44 × 0.33 × 0.30 mm
β = 96.709 (1)°

Data collection top

Bruker SMART APEXII CCD diffractometer	3529 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	3091 reflections with I > 2σ(I)
T_min = 0.692, T_max = 0.746	R_int = 0.033
25176 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.103	H-atom parameters constrained
S = 1.05	Δρ_max = 0.30 e Å⁻³
3529 reflections	Δρ_min = −0.27 e Å⁻³
184 parameters

Special details top

Experimental. ¹H NMR (δ p.p.m., CDCl₃, 400 Hz): 8.35 (d, J = 7.88 Hz, 1H), 7.53–7.57 (m, 1H), 7.38–7.42 (m, 1H), 7.26 (d, J = 7.02 Hz, 1H), 7.15 (d, J = 7.52 Hz, 1H), 6.98–7.03 (m, 2H), 2.73 (s, 3H), 2.25 (s, 3H), 2.13 (s, 3H),

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
S1	0.17973 (3)	0.37549 (4)	0.52324 (2)	0.02675 (11)
O1	0.17654 (10)	0.24730 (14)	0.75315 (6)	0.0349 (2)
O2	0.21361 (11)	0.55407 (13)	0.51308 (6)	0.0381 (3)
C1	0.21664 (12)	0.31930 (17)	0.62666 (8)	0.0250 (3)
C2	0.33439 (12)	0.30795 (16)	0.67783 (8)	0.0236 (3)
C3	0.45906 (12)	0.33131 (16)	0.66789 (8)	0.0255 (3)
H3	0.4825	0.3619	0.6160	0.031*
C4	0.54881 (13)	0.30933 (18)	0.73475 (9)	0.0307 (3)
C5	0.51194 (15)	0.2614 (2)	0.81059 (9)	0.0363 (3)
H5	0.5740	0.2456	0.8557	0.044*
C6	0.38937 (16)	0.23627 (19)	0.82225 (9)	0.0355 (3)
H6	0.3656	0.2031	0.8737	0.043*
C7	0.30345 (13)	0.26225 (18)	0.75471 (8)	0.0287 (3)
C8	0.12638 (13)	0.28335 (19)	0.67489 (9)	0.0304 (3)
C9	0.68418 (15)	0.3366 (2)	0.72713 (11)	0.0434 (4)
H9A	0.6941	0.3692	0.6708	0.065*
H9B	0.7301	0.2331	0.7408	0.065*
H9C	0.7165	0.4252	0.7648	0.065*
C10	−0.01086 (15)	0.2761 (3)	0.65979 (11)	0.0452 (4)
H10A	−0.0380	0.3087	0.6030	0.068*
H10B	−0.0466	0.3527	0.6972	0.068*
H10C	−0.0388	0.1622	0.6691	0.068*
C11	0.29473 (12)	0.25559 (17)	0.47850 (7)	0.0236 (3)
C12	0.38520 (14)	0.34425 (18)	0.44408 (8)	0.0297 (3)
H12	0.3893	0.4622	0.4493	0.036*
C13	0.46993 (15)	0.2599 (2)	0.40181 (9)	0.0365 (3)
H13	0.5331	0.3197	0.3788	0.044*
C14	0.46160 (15)	0.0895 (2)	0.39362 (9)	0.0363 (3)
H14	0.5183	0.0315	0.3639	0.044*
C15	0.37125 (14)	0.00203 (19)	0.42834 (9)	0.0338 (3)
H15	0.3675	−0.1159	0.4225	0.041*
C16	0.28551 (13)	0.08234 (18)	0.47168 (8)	0.0285 (3)
C17	0.18974 (17)	−0.0156 (2)	0.50997 (12)	0.0464 (4)
H17A	0.2083	−0.0119	0.5698	0.070*
H17B	0.1907	−0.1318	0.4914	0.070*
H17C	0.1075	0.0326	0.4938	0.070*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.02608 (18)	0.03273 (19)	0.02139 (17)	0.00435 (12)	0.00261 (12)	0.00056 (12)
O1	0.0357 (6)	0.0446 (6)	0.0266 (5)	−0.0031 (5)	0.0128 (4)	0.0039 (4)
O2	0.0555 (7)	0.0288 (5)	0.0317 (5)	0.0098 (5)	0.0130 (5)	0.0029 (4)
C1	0.0253 (6)	0.0285 (6)	0.0219 (6)	0.0001 (5)	0.0053 (5)	0.0000 (5)
C2	0.0290 (6)	0.0229 (6)	0.0194 (6)	0.0002 (5)	0.0046 (5)	−0.0003 (4)
C3	0.0266 (6)	0.0280 (6)	0.0220 (6)	−0.0007 (5)	0.0026 (5)	−0.0005 (5)
C4	0.0314 (7)	0.0304 (7)	0.0292 (7)	0.0008 (5)	−0.0014 (6)	−0.0019 (5)
C5	0.0433 (8)	0.0393 (8)	0.0238 (7)	0.0031 (6)	−0.0064 (6)	0.0009 (6)
C6	0.0515 (9)	0.0353 (8)	0.0198 (6)	0.0018 (7)	0.0052 (6)	0.0032 (5)
C7	0.0331 (7)	0.0312 (7)	0.0230 (6)	−0.0009 (5)	0.0084 (5)	0.0008 (5)
C8	0.0289 (7)	0.0362 (7)	0.0275 (7)	−0.0020 (5)	0.0089 (5)	−0.0005 (5)
C9	0.0293 (8)	0.0558 (10)	0.0424 (9)	−0.0019 (7)	−0.0066 (7)	−0.0019 (7)
C10	0.0281 (8)	0.0646 (11)	0.0451 (9)	−0.0056 (7)	0.0132 (7)	−0.0002 (8)
C11	0.0245 (6)	0.0286 (7)	0.0171 (5)	0.0019 (5)	0.0003 (5)	−0.0007 (4)
C12	0.0344 (7)	0.0309 (7)	0.0249 (6)	−0.0023 (5)	0.0073 (5)	−0.0004 (5)
C13	0.0363 (8)	0.0450 (9)	0.0304 (7)	0.0001 (6)	0.0128 (6)	0.0006 (6)
C14	0.0373 (8)	0.0457 (9)	0.0263 (7)	0.0124 (7)	0.0049 (6)	−0.0039 (6)
C15	0.0418 (8)	0.0299 (7)	0.0285 (7)	0.0069 (6)	−0.0015 (6)	−0.0039 (5)
C16	0.0313 (7)	0.0300 (7)	0.0232 (6)	−0.0014 (5)	−0.0011 (5)	−0.0005 (5)
C17	0.0526 (10)	0.0321 (8)	0.0570 (11)	−0.0126 (7)	0.0168 (8)	−0.0016 (7)

Geometric parameters (Å, º) top

S1—O2	1.4918 (11)	C9—H9B	0.9800
S1—C1	1.7580 (13)	C9—H9C	0.9800
S1—C11	1.7982 (13)	C10—H10A	0.9800
O1—C8	1.3671 (18)	C10—H10B	0.9800
O1—C7	1.3789 (17)	C10—H10C	0.9800
C1—C8	1.3604 (18)	C11—C12	1.3846 (19)
C1—C2	1.4476 (18)	C11—C16	1.3955 (19)
C2—C7	1.3932 (17)	C12—C13	1.390 (2)
C2—C3	1.3934 (18)	C12—H12	0.9500
C3—C4	1.3912 (19)	C13—C14	1.375 (2)
C3—H3	0.9500	C13—H13	0.9500
C4—C5	1.406 (2)	C14—C15	1.381 (2)
C4—C9	1.504 (2)	C14—H14	0.9500
C5—C6	1.380 (2)	C15—C16	1.393 (2)
C5—H5	0.9500	C15—H15	0.9500
C6—C7	1.379 (2)	C16—C17	1.498 (2)
C6—H6	0.9500	C17—H17A	0.9800
C8—C10	1.481 (2)	C17—H17B	0.9800
C9—H9A	0.9800	C17—H17C	0.9800

O2—S1—C1	108.82 (6)	H9A—C9—H9C	109.5
O2—S1—C11	105.97 (6)	H9B—C9—H9C	109.5
C1—S1—C11	99.66 (6)	C8—C10—H10A	109.5
C8—O1—C7	106.61 (10)	C8—C10—H10B	109.5
C8—C1—C2	107.12 (12)	H10A—C10—H10B	109.5
C8—C1—S1	121.27 (11)	C8—C10—H10C	109.5
C2—C1—S1	131.55 (10)	H10A—C10—H10C	109.5
C7—C2—C3	118.78 (12)	H10B—C10—H10C	109.5
C7—C2—C1	104.68 (11)	C12—C11—C16	121.69 (12)
C3—C2—C1	136.54 (12)	C12—C11—S1	116.82 (10)
C4—C3—C2	119.30 (13)	C16—C11—S1	121.19 (10)
C4—C3—H3	120.3	C11—C12—C13	119.74 (14)
C2—C3—H3	120.3	C11—C12—H12	120.1
C3—C4—C5	119.29 (13)	C13—C12—H12	120.1
C3—C4—C9	121.04 (14)	C14—C13—C12	119.48 (14)
C5—C4—C9	119.67 (14)	C14—C13—H13	120.3
C6—C5—C4	122.77 (13)	C12—C13—H13	120.3
C6—C5—H5	118.6	C13—C14—C15	120.36 (14)
C4—C5—H5	118.6	C13—C14—H14	119.8
C7—C6—C5	115.96 (13)	C15—C14—H14	119.8
C7—C6—H6	122.0	C14—C15—C16	121.67 (14)
C5—C6—H6	122.0	C14—C15—H15	119.2
O1—C7—C6	125.53 (13)	C16—C15—H15	119.2
O1—C7—C2	110.59 (12)	C15—C16—C11	117.05 (13)
C6—C7—C2	123.88 (14)	C15—C16—C17	120.63 (14)
C1—C8—O1	110.99 (12)	C11—C16—C17	122.31 (13)
C1—C8—C10	133.48 (14)	C16—C17—H17A	109.5
O1—C8—C10	115.53 (12)	C16—C17—H17B	109.5
C4—C9—H9A	109.5	H17A—C17—H17B	109.5
C4—C9—H9B	109.5	C16—C17—H17C	109.5
H9A—C9—H9B	109.5	H17A—C17—H17C	109.5
C4—C9—H9C	109.5	H17B—C17—H17C	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2ⁱ	0.95	2.45	3.3772 (18)	166
C17—H17B···O2ⁱⁱ	0.98	2.55	3.458 (2)	154

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2ⁱ	0.95	2.45	3.3772 (18)	165.5
C17—H17B···O2ⁱⁱ	0.98	2.55	3.458 (2)	153.9

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

Acknowledgements

This work was supported by a Dongeui University Grant (2015AA019). The X-ray centre of the Gyeongsang National University is acknowledged for providing access to the single-crystal diffractometer.

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