Ethyl 2-(3-ethyl­sulfinyl-5-methyl-1-benzo­furan-2-yl)acetate

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

doi:10.1107/S1600536809008460

organic compounds

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ISSN: 2056-9890

Volume 65| Part 4| April 2009| Page o763

doi:10.1107/S1600536809008460

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Ethyl 2-(3-ethylsulfinyl-5-methyl-1-benzofuran-2-yl)acetate

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 6 March 2009; accepted 8 March 2009; online 14 March 2009)

The title compound, C₁₅H₁₈O₄S, was prepared by the oxidation of ethyl 2-(3-ethylsulfanyl-5-methyl-1-benzofuran-2-yl)acetate with 3-chloroperoxybenzoic acid. The crystal structure is stabilized by aromatic π–π interactions between the benzene rings of neighbouring molecules [centroid–centroid distance = 3.655 (3) Å] and by three intermolecular C—H⋯O non-classical hydrogen bonds.

Related literature

For the crystal structures of similar alkyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate derivatives, see: Choi et al. (2008a ,b ).

Experimental

Crystal data

C₁₅H₁₈O₄S
M_r = 294.36
Monoclinic, P 2₁ /c
a = 7.9651 (5) Å
b = 17.397 (1) Å
c = 10.6902 (7) Å
β = 102.431 (1)°
V = 1446.60 (16) Å³
Z = 4
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 293 K
0.40 × 0.35 × 0.30 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: none
12350 measured reflections
3148 independent reflections
2949 reflections with I > 2σ(I)
R_int = 0.037

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.114
S = 1.27
3148 reflections
184 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.33 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O3ⁱ	0.93	2.64	3.507 (3)	155
C6—H6⋯O2ⁱⁱ	0.93	2.63	3.511 (3)	158
C9—H9B⋯O4ⁱⁱⁱ	0.97	2.20	3.161 (3)	169
Symmetry codes: (i) -x, -y+1, -z+1; (ii) -x+1, -y+1, -z+1; (iii) -x+1, -y+1, -z+2.

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT (Bruker, 2001); 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/S1600536809008460/rk2133sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809008460/rk2133Isup2.hkl

checkCIF report

Comment top

As a part of our continuing studies on the synthesis and structure of alkyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate analogues, we have recently described the crystal structure of methyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008a) and isopropyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008b). Here we report the crystal structure of the title compound, ethyl 2-(3-ethylsulfinyl-5-methyl-1-benzofuran-2-yl)acetate (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.009 (2) Å from the least-squares plane defined by the nine constituent atoms. The molecular packing (Fig. 2) is stabilized by aromatic π-π interactions between the benzene rings of the adjacent molecules, with a Cg···Cgⁱ distance of 3.655 (3) Å (Cg is the centroid of the C2-C7 benzene ring; symmetry codes as in Fig. 2). The crystal packing is further stabilized by intermolecular C–H···O nonclassical hydrogen bonds; one between a benzene-H atom and the O atom of the C═O unit, a second between a benzene-H atom and the O atom of the ethoxy group, a third between an H atom of the methylene group bonded to carboxylate C atom and the S═O unit, respectively (Table 1 and Fig. 2; symmetry codes as in Fig. 2).

Related literature top

For the crystal structures of similar alkyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate derivatives, see: Choi et al. (2008a,b).

Experimental top

The 77% 3-chloroperoxybenzoic acid (247 mg, 1.1 mmol) was added in small portions to a stirred solution of ethyl 2-(3-ethylsulfanyl-5-methyl-1-benzofuran-2-yl)acetate (278 mg, 1.0 mmol) in dichloromethane (30 ml) at 273 K. After being stirred for 3 h at room temperature, 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, 1:2 v/v) to afford the title compound as a colourless solid [yield 80%, m.p. 381-382 K; Rf = 0.51 (hexane-ethyl acetate, 1:2 v/v)]. Single crystals suitable for X-ray diffraction were prepared by evaporation of a solution of the title compound in acetone at room temperature. Spectroscopic analysis: ¹H NMR (CDCl₃, 400 MHz) δ 1.27 (t, J = 6.96 Hz, 3H), 1.32 (t, J = 7.32 Hz, 3H), 2.45 (s, 3H), 3.31 (q, J = 7.32 Hz, 2H), 4.04 (s, 2H), 4.20 (q, J = 7.32 Hz, 2H), 7.17 (dd, J = 8.44 Hz and 1.48 Hz, 1H), 7.39 (d, J = 8.44 Hz, 1H), 7.66 (s, 1H); EI–MS 294 [M⁺].

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); 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. π-π and C–H···O interactions (dotted lines) in the title crystal structure. Cg denotes ring centroid. [Symmetry codes: (i) -x, -y+1, -z+1; (ii) -x+1, -y+1, -z+1; (iii) -x+1, -y+1, -z+2; (iv) x+1, y, z].

Ethyl 2-(3-ethylsulfinyl-5-methyl-1-benzofuran-2-yl)acetate top

Crystal data top

C₁₅H₁₈O₄S	F(000) = 624
M_r = 294.36	D_x = 1.352 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7772 reflections
a = 7.9651 (5) Å	θ = 2.3–28.2°
b = 17.397 (1) Å	µ = 0.23 mm⁻¹
c = 10.6902 (7) Å	T = 293 K
β = 102.431 (1)°	Block, colourless
V = 1446.60 (16) Å³	0.40 × 0.35 × 0.30 mm
Z = 4

Data collection top

Bruker SMART CCD diffractometer	2949 reflections with I > 2σ(I)
Radiation source: Fine-focus sealed tube	R_int = 0.037
Graphite monochromator	θ_max = 27.0°, θ_min = 2.3°
Detector resolution: 10.0 pixels mm^-1	h = −10→10
ϕ and ω scans	k = −22→22
12350 measured reflections	l = −13→13
3148 independent reflections

Refinement top

Refinement on F²	Primary atom site location: Direct
Least-squares matrix: Full	Secondary atom site location: Difmap
R[F² > 2σ(F²)] = 0.052	Hydrogen site location: Difmap
wR(F²) = 0.114	H-atom parameters constrained
S = 1.27	w = 1/[σ²(F_o²) + (0.0313P)² + 1.0305P] where P = (F_o² + 2F_c²)/3
3148 reflections	(Δ/σ)_max < 0.001
184 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.33 e Å⁻³

Crystal data top

C₁₅H₁₈O₄S	V = 1446.60 (16) Å³
M_r = 294.36	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.9651 (5) Å	µ = 0.23 mm⁻¹
b = 17.397 (1) Å	T = 293 K
c = 10.6902 (7) Å	0.40 × 0.35 × 0.30 mm
β = 102.431 (1)°

Data collection top

Bruker SMART CCD diffractometer	2949 reflections with I > 2σ(I)
12350 measured reflections	R_int = 0.037
3148 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.114	H-atom parameters constrained
S = 1.27	Δρ_max = 0.28 e Å⁻³
3148 reflections	Δρ_min = −0.33 e Å⁻³
184 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
S	0.28613 (7)	0.56219 (3)	0.92537 (5)	0.02864 (15)
O1	0.34278 (18)	0.48031 (8)	0.59291 (13)	0.0264 (3)
O2	0.69183 (19)	0.68219 (9)	0.71529 (15)	0.0346 (4)
O3	0.4106 (2)	0.68573 (9)	0.71809 (18)	0.0420 (4)
O4	0.2363 (2)	0.50522 (10)	1.01572 (15)	0.0407 (4)
C1	0.2712 (3)	0.51603 (11)	0.77684 (19)	0.0251 (4)
C2	0.1341 (3)	0.46731 (11)	0.70835 (19)	0.0243 (4)
C3	−0.0237 (3)	0.44088 (11)	0.72840 (19)	0.0267 (4)
H3	−0.0606	0.4539	0.8025	0.032*
C4	−0.1244 (3)	0.39479 (11)	0.6356 (2)	0.0284 (4)
C5	−0.0667 (3)	0.37595 (12)	0.5239 (2)	0.0303 (5)
H5	−0.1357	0.3453	0.4623	0.036*
C6	0.0892 (3)	0.40148 (12)	0.5024 (2)	0.0293 (4)
H6	0.1266	0.3886	0.4285	0.035*
C7	0.1861 (2)	0.44711 (11)	0.59661 (19)	0.0245 (4)
C8	0.3903 (3)	0.52184 (11)	0.70459 (19)	0.0253 (4)
C9	0.5568 (3)	0.56329 (12)	0.7224 (2)	0.0284 (4)
H9A	0.6154	0.5470	0.6563	0.034*
H9B	0.6280	0.5487	0.8045	0.034*
C10	0.5396 (3)	0.64999 (12)	0.71761 (19)	0.0278 (4)
C11	0.6973 (3)	0.76628 (13)	0.7098 (2)	0.0398 (6)
H11A	0.8137	0.7838	0.7442	0.048*
H11B	0.6235	0.7877	0.7623	0.048*
C12	0.6400 (4)	0.79423 (16)	0.5758 (3)	0.0537 (7)
H12A	0.7059	0.7693	0.5222	0.080*
H12B	0.6567	0.8488	0.5734	0.080*
H12C	0.5203	0.7826	0.5454	0.080*
C13	−0.2954 (3)	0.36439 (14)	0.6536 (2)	0.0385 (5)
H13A	−0.2898	0.3094	0.6617	0.058*
H13B	−0.3839	0.3782	0.5810	0.058*
H13C	−0.3213	0.3863	0.7298	0.058*
C14	0.1037 (3)	0.62590 (13)	0.8750 (2)	0.0352 (5)
H14A	0.1247	0.6597	0.8078	0.042*
H14B	0.0016	0.5958	0.8406	0.042*
C15	0.0745 (4)	0.67308 (15)	0.9860 (2)	0.0464 (6)
H15A	0.0334	0.6405	1.0455	0.070*
H15B	−0.0093	0.7122	0.9555	0.070*
H15C	0.1806	0.6967	1.0281	0.070*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S	0.0286 (3)	0.0315 (3)	0.0249 (3)	0.0021 (2)	0.00368 (19)	−0.0026 (2)
O1	0.0259 (7)	0.0274 (7)	0.0267 (7)	0.0001 (6)	0.0075 (6)	−0.0001 (6)
O2	0.0277 (8)	0.0286 (8)	0.0471 (9)	−0.0027 (6)	0.0068 (7)	0.0024 (7)
O3	0.0333 (9)	0.0303 (8)	0.0651 (12)	0.0018 (7)	0.0169 (8)	−0.0043 (8)
O4	0.0523 (10)	0.0428 (9)	0.0289 (8)	0.0086 (8)	0.0132 (7)	0.0077 (7)
C1	0.0267 (10)	0.0232 (10)	0.0251 (10)	0.0009 (8)	0.0047 (8)	0.0020 (8)
C2	0.0265 (10)	0.0199 (9)	0.0255 (10)	0.0029 (8)	0.0038 (8)	0.0044 (7)
C3	0.0286 (10)	0.0245 (10)	0.0281 (10)	0.0022 (8)	0.0084 (8)	0.0053 (8)
C4	0.0262 (10)	0.0218 (10)	0.0358 (11)	0.0017 (8)	0.0037 (8)	0.0066 (8)
C5	0.0316 (11)	0.0225 (10)	0.0331 (11)	0.0012 (8)	−0.0012 (8)	0.0003 (8)
C6	0.0347 (11)	0.0249 (10)	0.0277 (11)	0.0034 (9)	0.0056 (8)	−0.0003 (8)
C7	0.0230 (10)	0.0211 (9)	0.0294 (10)	0.0025 (8)	0.0055 (8)	0.0034 (8)
C8	0.0249 (10)	0.0228 (9)	0.0273 (10)	0.0033 (8)	0.0035 (8)	0.0030 (8)
C9	0.0244 (10)	0.0270 (10)	0.0340 (11)	0.0008 (8)	0.0072 (8)	0.0018 (8)
C10	0.0270 (10)	0.0297 (11)	0.0266 (10)	−0.0019 (8)	0.0055 (8)	−0.0016 (8)
C11	0.0368 (13)	0.0275 (11)	0.0533 (15)	−0.0086 (10)	0.0056 (11)	−0.0040 (10)
C12	0.0513 (16)	0.0412 (14)	0.0632 (18)	−0.0083 (12)	0.0006 (13)	0.0123 (13)
C13	0.0309 (12)	0.0327 (12)	0.0513 (14)	−0.0050 (9)	0.0078 (10)	0.0045 (10)
C14	0.0357 (12)	0.0345 (12)	0.0353 (12)	0.0064 (10)	0.0077 (9)	0.0016 (9)
C15	0.0588 (17)	0.0400 (14)	0.0425 (14)	0.0167 (12)	0.0150 (12)	0.0009 (11)

Geometric parameters (Å, º) top

S—O4	1.4960 (17)	C8—C9	1.485 (3)
S—C1	1.760 (2)	C9—C10	1.514 (3)
S—C14	1.815 (2)	C9—H9A	0.9700
O1—C8	1.377 (2)	C9—H9B	0.9700
O1—C7	1.384 (2)	C11—C12	1.488 (4)
O2—C10	1.341 (2)	C11—H11A	0.9700
O2—C11	1.465 (3)	C11—H11B	0.9700
O3—C10	1.202 (3)	C12—H12A	0.9600
C1—C8	1.350 (3)	C12—H12B	0.9600
C1—C2	1.450 (3)	C12—H12C	0.9600
C2—C7	1.391 (3)	C13—H13A	0.9600
C2—C3	1.398 (3)	C13—H13B	0.9600
C3—C4	1.388 (3)	C13—H13C	0.9600
C3—H3	0.9300	C14—C15	1.502 (3)
C4—C5	1.408 (3)	C14—H14A	0.9700
C4—C13	1.512 (3)	C14—H14B	0.9700
C5—C6	1.383 (3)	C15—H15A	0.9600
C5—H5	0.9300	C15—H15B	0.9600
C6—C7	1.380 (3)	C15—H15C	0.9600
C6—H6	0.9300

O4—S—C1	107.72 (10)	H9A—C9—H9B	107.6
O4—S—C14	106.81 (10)	O3—C10—O2	124.1 (2)
C1—S—C14	96.70 (10)	O3—C10—C9	125.91 (19)
C8—O1—C7	105.99 (15)	O2—C10—C9	109.95 (17)
C10—O2—C11	116.92 (17)	O2—C11—C12	111.1 (2)
C8—C1—C2	107.49 (18)	O2—C11—H11A	109.4
C8—C1—S	124.25 (16)	C12—C11—H11A	109.4
C2—C1—S	128.26 (15)	O2—C11—H11B	109.4
C7—C2—C3	119.49 (19)	C12—C11—H11B	109.4
C7—C2—C1	104.49 (17)	H11A—C11—H11B	108.0
C3—C2—C1	136.00 (19)	C11—C12—H12A	109.5
C4—C3—C2	118.71 (19)	C11—C12—H12B	109.5
C4—C3—H3	120.6	H12A—C12—H12B	109.5
C2—C3—H3	120.6	C11—C12—H12C	109.5
C3—C4—C5	119.81 (19)	H12A—C12—H12C	109.5
C3—C4—C13	120.5 (2)	H12B—C12—H12C	109.5
C5—C4—C13	119.7 (2)	C4—C13—H13A	109.5
C6—C5—C4	122.3 (2)	C4—C13—H13B	109.5
C6—C5—H5	118.8	H13A—C13—H13B	109.5
C4—C5—H5	118.8	C4—C13—H13C	109.5
C7—C6—C5	116.40 (19)	H13A—C13—H13C	109.5
C7—C6—H6	121.8	H13B—C13—H13C	109.5
C5—C6—H6	121.8	C15—C14—S	110.46 (17)
C6—C7—O1	125.83 (18)	C15—C14—H14A	109.6
C6—C7—C2	123.28 (19)	S—C14—H14A	109.6
O1—C7—C2	110.86 (17)	C15—C14—H14B	109.6
C1—C8—O1	111.17 (17)	S—C14—H14B	109.6
C1—C8—C9	132.92 (19)	H14A—C14—H14B	108.1
O1—C8—C9	115.91 (17)	C14—C15—H15A	109.5
C8—C9—C10	114.04 (17)	C14—C15—H15B	109.5
C8—C9—H9A	108.7	H15A—C15—H15B	109.5
C10—C9—H9A	108.7	C14—C15—H15C	109.5
C8—C9—H9B	108.7	H15A—C15—H15C	109.5
C10—C9—H9B	108.7	H15B—C15—H15C	109.5

O4—S—C1—C8	−135.83 (18)	C3—C2—C7—C6	−0.1 (3)
C14—S—C1—C8	114.09 (19)	C1—C2—C7—C6	−178.86 (18)
O4—S—C1—C2	45.4 (2)	C3—C2—C7—O1	178.44 (17)
C14—S—C1—C2	−64.7 (2)	C1—C2—C7—O1	−0.3 (2)
C8—C1—C2—C7	0.3 (2)	C2—C1—C8—O1	−0.2 (2)
S—C1—C2—C7	179.27 (15)	S—C1—C8—O1	−179.20 (13)
C8—C1—C2—C3	−178.1 (2)	C2—C1—C8—C9	179.7 (2)
S—C1—C2—C3	0.8 (3)	S—C1—C8—C9	0.7 (3)
C7—C2—C3—C4	0.1 (3)	C7—O1—C8—C1	0.0 (2)
C1—C2—C3—C4	178.4 (2)	C7—O1—C8—C9	−179.93 (16)
C2—C3—C4—C5	−0.3 (3)	C1—C8—C9—C10	−67.8 (3)
C2—C3—C4—C13	179.55 (18)	O1—C8—C9—C10	112.1 (2)
C3—C4—C5—C6	0.3 (3)	C11—O2—C10—O3	−1.6 (3)
C13—C4—C5—C6	−179.5 (2)	C11—O2—C10—C9	179.64 (18)
C4—C5—C6—C7	−0.3 (3)	C8—C9—C10—O3	10.4 (3)
C5—C6—C7—O1	−178.14 (18)	C8—C9—C10—O2	−170.85 (17)
C5—C6—C7—C2	0.2 (3)	C10—O2—C11—C12	−83.1 (3)
C8—O1—C7—C6	178.71 (19)	O4—S—C14—C15	66.5 (2)
C8—O1—C7—C2	0.2 (2)	C1—S—C14—C15	177.38 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O3ⁱ	0.93	2.64	3.507 (3)	155
C6—H6···O2ⁱⁱ	0.93	2.63	3.511 (3)	158
C9—H9B···O4ⁱⁱⁱ	0.97	2.20	3.161 (3)	169

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₈O₄S
M_r	294.36
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	7.9651 (5), 17.397 (1), 10.6902 (7)
β (°)	102.431 (1)
V (Å³)	1446.60 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.40 × 0.35 × 0.30

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	12350, 3148, 2949
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.114, 1.27
No. of reflections	3148
No. of parameters	184
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.33

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), 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
C5—H5···O3ⁱ	0.93	2.64	3.507 (3)	154.7
C6—H6···O2ⁱⁱ	0.93	2.63	3.511 (3)	157.8
C9—H9B···O4ⁱⁱⁱ	0.97	2.20	3.161 (3)	169.1

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

References

Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008a). Acta Cryst. E64, o1711. Web of Science CSD CrossRef IUCr Journals Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008b). Acta Cryst. E64, o2079. Web of Science CSD CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar

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Volume 65| Part 4| April 2009| Page o763

doi:10.1107/S1600536809008460

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