Diethyl 2,2′-(biphenyl-2,2′-diyldi­oxy)diacetate

Ali, Q.; Anis, I.; VanDerveer, D.; Shah, M.R.

doi:10.1107/S1600536810026863

organic compounds

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ISSN: 2056-9890

Volume 66| Part 8| August 2010| Page o1984

https://doi.org/10.1107/S1600536810026863

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Diethyl 2,2′-(biphenyl-2,2′-diyldioxy)diacetate

Qamar Ali,^a Itrat Anis,^b Donald VanDerveer ^c and Muhammad Raza Shah ^a ^*

^aH.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan, ^bDepartment of Chemistry, University of Karachi, Karachi 75270, Pakistan, and ^cChemistry Department, Clemson University, Clemson, SC 29634-0973, USA
^*Correspondence e-mail: raza_shahm@yahoo.com

(Received 16 June 2010; accepted 7 July 2010; online 10 July 2010)

In the title compound, C₂₀H₂₂O₆, the mean planes through the benzene rings make a dihedral angle of 59.82 (7)° with each other. Weak intermolecular C—H⋯O interactions together with π–π stacking interactions [centroid–centroid distance = 3.830 (1) Å] between benzene rings are observed in the crystal packing.

Related literature

For related structures, see: Rabnawaz et al. (2008 ); Ali et al. (2008 ); Ibad et al. (2008 ).

Experimental

Crystal data

C₂₀H₂₂O₆
M_r = 358.38
Triclinic, $[P \overline 1]$
a = 7.4683 (13) Å
b = 10.8189 (15) Å
c = 12.050 (2) Å
α = 104.733 (17)°
β = 95.05 (2)°
γ = 106.897 (14)°
V = 887.1 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 153 K
0.58 × 0.53 × 0.24 mm

Data collection

Rigaku AFC-8S diffractometer
Absorption correction: multi-scan (REQAB; Jacobson, 1998 ) T_min = 0.945, T_max = 0.977
6640 measured reflections
3104 independent reflections
2787 reflections with I > 2σ(I)
R_int = 0.014

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.099
S = 1.04
3104 reflections
235 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4b⋯O1ⁱ	0.99	2.50	3.472 (2)	168 (1)
Symmetry code: (i) -x+1, -y+1, -z.

Data collection: CrystalClear (Rigaku/MSC, 2006 ); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810026863/ez2221sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810026863/ez2221Isup2.hkl

checkCIF report

Comment top

In the continuation of our work on biphenyl derivatives (Rabnawaz et al., 2008) we report here the synthesis and crystal structure of the title compound, I. The molecular structure and atom-numbering scheme of the title compound are shown in Fig. 1. The molecules are essentially non-planar, with a dihedral angle of 59.82 (7)° between the mean planes through the benzene rings. This is slightly more than the corresponding tert butyl ester analogue of I (Ali et al., 2008), due to the presence of the sterically less crowded ethyl ester group. The key C=O and C—O bond distances are in agreement with those observed in the related hydrazide structure (Ibad et al., 2008). NMR data show that the molecule has a non-crystallographic two-fold rotation axis.

Related literature top

For related structures, see: Rabnawaz et al. (2008); Ali et al. (2008); Ibad et al. (2008).

Experimental top

K₂CO₃ (414 mg, 3 mmol) and 2,2'-dihydroxybiphenyl (186 mg,1 mmol) in 15 ml of acetone were stirred for 10 minutes, followed by addition of ethyl bromoacetate (314 mg, 3 mmol). The reaction mixture was stirred at room temperature for three hours. The solvent was evaporated under reduced pressure and the residue was dissolved in a mixture of water (50 ml) and dichloromethane (50 ml). The aqueous layer was extracted three times with dichloromethane. The combined organic phases were evaporated under reduced pressure and the solid residue was dissolved in ethanol. Slow evaporation of ethanol gave colorless crystals (736 mg) in 80% yield.

Structure description top

For related structures, see: Rabnawaz et al. (2008); Ali et al. (2008); Ibad et al. (2008).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2006); cell refinement: CrystalClear (Rigaku/MSC, 2006); data reduction: CrystalClear (Rigaku/MSC, 2006); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of (I) with atom labels and 30% probability displacement ellipsoids.

Diethyl 2,2'-(biphenyl-2,2'-diyldioxy)diacetate top

Crystal data top

C₂₀H₂₂O₆	Z = 2
M_r = 358.38	F(000) = 380
Triclinic, P1	D_x = 1.342 Mg m⁻³
a = 7.4683 (13) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.8189 (15) Å	Cell parameters from 2971 reflections
c = 12.050 (2) Å	θ = 3.1–26.3°
α = 104.733 (17)°	µ = 0.10 mm⁻¹
β = 95.05 (2)°	T = 153 K
γ = 106.897 (14)°	Chip, colorless
V = 887.1 (3) Å³	0.58 × 0.53 × 0.24 mm

Data collection top

Rigaku AFC-8S diffractometer	3104 independent reflections
Radiation source: normal-focus sealed tube	2787 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.014
Detector resolution: 14.6306 pixels mm^-1	θ_max = 25.1°, θ_min = 3.1°
ω scans	h = −8→8
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	k = −12→12
T_min = 0.945, T_max = 0.977	l = −14→12
6640 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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.099	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0493P)² + 0.3462P] where P = (F_o² + 2F_c²)/3
3104 reflections	(Δ/σ)_max < 0.001
235 parameters	Δρ_max = 0.18 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₂₀H₂₂O₆	γ = 106.897 (14)°
M_r = 358.38	V = 887.1 (3) Å³
Triclinic, P1	Z = 2
a = 7.4683 (13) Å	Mo Kα radiation
b = 10.8189 (15) Å	µ = 0.10 mm⁻¹
c = 12.050 (2) Å	T = 153 K
α = 104.733 (17)°	0.58 × 0.53 × 0.24 mm
β = 95.05 (2)°

Data collection top

Rigaku AFC-8S diffractometer	3104 independent reflections
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	2787 reflections with I > 2σ(I)
T_min = 0.945, T_max = 0.977	R_int = 0.014
6640 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.099	H-atom parameters constrained
S = 1.04	Δρ_max = 0.18 e Å⁻³
3104 reflections	Δρ_min = −0.20 e Å⁻³
235 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
O1	0.26152 (13)	0.49153 (10)	−0.09823 (8)	0.0281 (2)
O2	0.10844 (14)	0.63977 (10)	−0.03410 (9)	0.0289 (3)
O3	0.37964 (13)	0.73993 (9)	0.17431 (8)	0.0229 (2)
O4	0.64269 (14)	1.13019 (10)	0.42800 (8)	0.0270 (2)
O5	0.71807 (19)	1.39716 (12)	0.43450 (10)	0.0455 (3)
O6	0.74896 (14)	1.45726 (9)	0.62997 (8)	0.0284 (2)
C1	0.2426 (2)	0.36891 (16)	−0.29568 (13)	0.0315 (3)
H1A	0.1754	0.3436	−0.3759	0.047*
H1B	0.2329	0.2872	−0.2723	0.047*
H1C	0.3768	0.4191	−0.2912	0.047*
C2	0.1555 (2)	0.45549 (19)	−0.21611 (13)	0.0407 (4)
H2A	0.1631	0.5380	−0.2395	0.049*
H2B	0.0201	0.4056	−0.2194	0.049*
C3	0.22147 (18)	0.58407 (13)	−0.01637 (12)	0.0213 (3)
C4	0.33426 (18)	0.60535 (13)	0.10190 (11)	0.0218 (3)
H4A	0.2593	0.5424	0.1406	0.026*
H4B	0.4532	0.5843	0.0911	0.026*
C5	0.50568 (17)	0.83979 (13)	0.14036 (11)	0.0197 (3)
C6	0.51573 (18)	0.97228 (13)	0.19636 (11)	0.0196 (3)
C7	0.64460 (19)	1.07739 (13)	0.16831 (12)	0.0239 (3)
H7A	0.6553	1.1682	0.2068	0.029*
C8	0.75716 (19)	1.05198 (14)	0.08549 (12)	0.0261 (3)
H8A	0.8428	1.1247	0.0667	0.031*
C9	0.74388 (19)	0.92018 (15)	0.03053 (12)	0.0267 (3)
H9A	0.8203	0.9023	−0.0266	0.032*
C10	0.61985 (19)	0.81358 (14)	0.05811 (12)	0.0244 (3)
H10A	0.6129	0.7232	0.0210	0.029*
C11	0.38246 (18)	1.00240 (13)	0.27616 (11)	0.0207 (3)
C12	0.18639 (19)	0.95132 (13)	0.23529 (12)	0.0242 (3)
H12A	0.1391	0.8899	0.1593	0.029*
C13	0.0593 (2)	0.98855 (14)	0.30363 (13)	0.0277 (3)
H13A	−0.0734	0.9537	0.2745	0.033*
C14	0.1289 (2)	1.07714 (14)	0.41479 (13)	0.0297 (3)
H14A	0.0430	1.1041	0.4615	0.036*
C15	0.3225 (2)	1.12712 (14)	0.45896 (13)	0.0281 (3)
H15A	0.3685	1.1868	0.5358	0.034*
C16	0.44882 (19)	1.08923 (13)	0.39009 (12)	0.0223 (3)
C17	0.7184 (2)	1.23201 (14)	0.53605 (12)	0.0284 (3)
H17A	0.8479	1.2336	0.5641	0.034*
H17B	0.6384	1.2107	0.5943	0.034*
C18	0.72672 (19)	1.36982 (14)	0.52501 (12)	0.0263 (3)
C19	0.7734 (2)	1.59703 (14)	0.63189 (14)	0.0349 (4)
H19A	0.6748	1.5994	0.5726	0.042*
H19B	0.8998	1.6391	0.6141	0.042*
C20	0.7560 (2)	1.67243 (15)	0.75077 (14)	0.0352 (4)
H20A	0.7719	1.7665	0.7541	0.053*
H20B	0.8544	1.6699	0.8088	0.053*
H20C	0.6303	1.6303	0.7674	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0283 (5)	0.0326 (6)	0.0214 (5)	0.0160 (4)	0.0003 (4)	−0.0010 (4)
O2	0.0284 (5)	0.0264 (5)	0.0338 (6)	0.0133 (4)	0.0033 (4)	0.0075 (4)
O3	0.0279 (5)	0.0169 (5)	0.0224 (5)	0.0059 (4)	0.0092 (4)	0.0032 (4)
O4	0.0303 (5)	0.0263 (5)	0.0210 (5)	0.0131 (4)	0.0000 (4)	−0.0019 (4)
O5	0.0766 (9)	0.0358 (6)	0.0258 (6)	0.0188 (6)	0.0108 (6)	0.0107 (5)
O6	0.0422 (6)	0.0211 (5)	0.0213 (5)	0.0123 (4)	0.0035 (4)	0.0036 (4)
C1	0.0309 (7)	0.0337 (8)	0.0238 (8)	0.0074 (6)	0.0037 (6)	0.0020 (6)
C2	0.0376 (8)	0.0587 (11)	0.0225 (8)	0.0246 (8)	−0.0030 (6)	−0.0013 (7)
C3	0.0195 (6)	0.0172 (6)	0.0270 (7)	0.0054 (5)	0.0068 (5)	0.0058 (5)
C4	0.0249 (7)	0.0167 (6)	0.0235 (7)	0.0077 (5)	0.0054 (5)	0.0039 (5)
C5	0.0204 (6)	0.0194 (6)	0.0174 (6)	0.0047 (5)	0.0021 (5)	0.0046 (5)
C6	0.0210 (6)	0.0202 (6)	0.0170 (6)	0.0075 (5)	0.0013 (5)	0.0041 (5)
C7	0.0269 (7)	0.0203 (7)	0.0225 (7)	0.0067 (5)	0.0021 (5)	0.0047 (5)
C8	0.0241 (7)	0.0269 (7)	0.0254 (7)	0.0039 (5)	0.0052 (5)	0.0093 (6)
C9	0.0247 (7)	0.0315 (7)	0.0212 (7)	0.0068 (6)	0.0082 (5)	0.0044 (6)
C10	0.0257 (7)	0.0221 (7)	0.0219 (7)	0.0071 (5)	0.0053 (5)	0.0008 (5)
C11	0.0265 (7)	0.0172 (6)	0.0212 (7)	0.0094 (5)	0.0063 (5)	0.0072 (5)
C12	0.0288 (7)	0.0193 (6)	0.0265 (7)	0.0088 (5)	0.0067 (6)	0.0085 (5)
C13	0.0268 (7)	0.0240 (7)	0.0373 (8)	0.0098 (6)	0.0119 (6)	0.0138 (6)
C14	0.0370 (8)	0.0264 (7)	0.0356 (8)	0.0171 (6)	0.0198 (6)	0.0138 (6)
C15	0.0399 (8)	0.0242 (7)	0.0241 (7)	0.0153 (6)	0.0117 (6)	0.0063 (6)
C16	0.0290 (7)	0.0189 (6)	0.0217 (7)	0.0110 (5)	0.0054 (5)	0.0067 (5)
C17	0.0362 (8)	0.0254 (7)	0.0206 (7)	0.0137 (6)	−0.0020 (6)	0.0000 (6)
C18	0.0289 (7)	0.0281 (7)	0.0200 (7)	0.0096 (6)	0.0026 (5)	0.0040 (6)
C19	0.0524 (9)	0.0208 (7)	0.0330 (9)	0.0128 (7)	0.0078 (7)	0.0094 (6)
C20	0.0516 (9)	0.0201 (7)	0.0318 (8)	0.0105 (7)	0.0062 (7)	0.0056 (6)

Geometric parameters (Å, º) top

O1—C3	1.3374 (16)	C8—C9	1.381 (2)
O1—C2	1.4618 (18)	C8—H8A	0.9500
O2—C3	1.2044 (16)	C9—C10	1.388 (2)
O3—C5	1.3864 (16)	C9—H9A	0.9500
O3—C4	1.4181 (16)	C10—H10A	0.9500
O4—C16	1.3816 (17)	C11—C12	1.399 (2)
O4—C17	1.4167 (17)	C11—C16	1.402 (2)
O5—C18	1.2017 (18)	C12—C13	1.3900 (19)
O6—C18	1.3362 (17)	C12—H12A	0.9500
O6—C19	1.4634 (17)	C13—C14	1.385 (2)
C1—C2	1.492 (2)	C13—H13A	0.9500
C1—H1A	0.9800	C14—C15	1.389 (2)
C1—H1B	0.9800	C14—H14A	0.9500
C1—H1C	0.9800	C15—C16	1.3913 (19)
C2—H2A	0.9900	C15—H15A	0.9500
C2—H2B	0.9900	C17—C18	1.514 (2)
C3—C4	1.5175 (19)	C17—H17A	0.9900
C4—H4A	0.9900	C17—H17B	0.9900
C4—H4B	0.9900	C19—C20	1.495 (2)
C5—C10	1.3916 (18)	C19—H19A	0.9900
C5—C6	1.3971 (18)	C19—H19B	0.9900
C6—C7	1.3966 (19)	C20—H20A	0.9800
C6—C11	1.4897 (18)	C20—H20B	0.9800
C7—C8	1.386 (2)	C20—H20C	0.9800
C7—H7A	0.9500

C3—O1—C2	116.34 (11)	C9—C10—H10A	120.2
C5—O3—C4	116.66 (10)	C5—C10—H10A	120.2
C16—O4—C17	117.43 (11)	C12—C11—C16	118.38 (12)
C18—O6—C19	115.91 (11)	C12—C11—C6	119.93 (12)
C2—C1—H1A	109.5	C16—C11—C6	121.54 (12)
C2—C1—H1B	109.5	C13—C12—C11	121.36 (13)
H1A—C1—H1B	109.5	C13—C12—H12A	119.3
C2—C1—H1C	109.5	C11—C12—H12A	119.3
H1A—C1—H1C	109.5	C14—C13—C12	119.08 (13)
H1B—C1—H1C	109.5	C14—C13—H13A	120.5
O1—C2—C1	107.38 (12)	C12—C13—H13A	120.5
O1—C2—H2A	110.2	C13—C14—C15	120.95 (13)
C1—C2—H2A	110.2	C13—C14—H14A	119.5
O1—C2—H2B	110.2	C15—C14—H14A	119.5
C1—C2—H2B	110.2	C14—C15—C16	119.63 (14)
H2A—C2—H2B	108.5	C14—C15—H15A	120.2
O2—C3—O1	124.57 (13)	C16—C15—H15A	120.2
O2—C3—C4	125.14 (12)	O4—C16—C15	123.64 (12)
O1—C3—C4	110.27 (11)	O4—C16—C11	115.79 (12)
O3—C4—C3	111.80 (11)	C15—C16—C11	120.56 (13)
O3—C4—H4A	109.3	O4—C17—C18	111.40 (12)
C3—C4—H4A	109.3	O4—C17—H17A	109.3
O3—C4—H4B	109.3	C18—C17—H17A	109.3
C3—C4—H4B	109.3	O4—C17—H17B	109.3
H4A—C4—H4B	107.9	C18—C17—H17B	109.3
O3—C5—C10	123.59 (12)	H17A—C17—H17B	108.0
O3—C5—C6	115.63 (11)	O5—C18—O6	124.81 (13)
C10—C5—C6	120.77 (12)	O5—C18—C17	124.61 (13)
C7—C6—C5	118.18 (12)	O6—C18—C17	110.57 (12)
C7—C6—C11	119.86 (12)	O6—C19—C20	108.07 (12)
C5—C6—C11	121.75 (12)	O6—C19—H19A	110.1
C8—C7—C6	121.36 (13)	C20—C19—H19A	110.1
C8—C7—H7A	119.3	O6—C19—H19B	110.1
C6—C7—H7A	119.3	C20—C19—H19B	110.1
C9—C8—C7	119.49 (13)	H19A—C19—H19B	108.4
C9—C8—H8A	120.3	C19—C20—H20A	109.5
C7—C8—H8A	120.3	C19—C20—H20B	109.5
C8—C9—C10	120.55 (13)	H20A—C20—H20B	109.5
C8—C9—H9A	119.7	C19—C20—H20C	109.5
C10—C9—H9A	119.7	H20A—C20—H20C	109.5
C9—C10—C5	119.64 (13)	H20B—C20—H20C	109.5

C3—O1—C2—C1	171.24 (12)	C7—C6—C11—C16	−58.95 (18)
C2—O1—C3—O2	−1.3 (2)	C5—C6—C11—C16	126.46 (14)
C2—O1—C3—C4	176.98 (12)	C16—C11—C12—C13	2.17 (19)
C5—O3—C4—C3	−67.26 (14)	C6—C11—C12—C13	−173.39 (12)
O2—C3—C4—O3	−33.27 (18)	C11—C12—C13—C14	−0.6 (2)
O1—C3—C4—O3	148.41 (11)	C12—C13—C14—C15	−1.0 (2)
C4—O3—C5—C10	−15.26 (18)	C13—C14—C15—C16	0.9 (2)
C4—O3—C5—C6	166.12 (11)	C17—O4—C16—C15	−9.89 (19)
O3—C5—C6—C7	178.06 (11)	C17—O4—C16—C11	171.55 (11)
C10—C5—C6—C7	−0.60 (19)	C14—C15—C16—O4	−177.75 (12)
O3—C5—C6—C11	−7.26 (18)	C14—C15—C16—C11	0.8 (2)
C10—C5—C6—C11	174.08 (12)	C12—C11—C16—O4	176.37 (11)
C5—C6—C7—C8	1.4 (2)	C6—C11—C16—O4	−8.15 (18)
C11—C6—C7—C8	−173.42 (12)	C12—C11—C16—C15	−2.24 (19)
C6—C7—C8—C9	−0.9 (2)	C6—C11—C16—C15	173.24 (12)
C7—C8—C9—C10	−0.4 (2)	C16—O4—C17—C18	−75.23 (15)
C8—C9—C10—C5	1.1 (2)	C19—O6—C18—O5	−3.1 (2)
O3—C5—C10—C9	−179.17 (12)	C19—O6—C18—C17	175.61 (12)
C6—C5—C10—C9	−0.6 (2)	O4—C17—C18—O5	−17.8 (2)
C7—C6—C11—C12	116.47 (14)	O4—C17—C18—O6	163.46 (11)
C5—C6—C11—C12	−58.13 (18)	C18—O6—C19—C20	168.59 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4b···O1ⁱ	0.99	2.50	3.472 (2)	168 (1)

Symmetry code: (i) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₂₀H₂₂O₆
M_r	358.38
Crystal system, space group	Triclinic, P1
Temperature (K)	153
a, b, c (Å)	7.4683 (13), 10.8189 (15), 12.050 (2)
α, β, γ (°)	104.733 (17), 95.05 (2), 106.897 (14)
V (Å³)	887.1 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.58 × 0.53 × 0.24

Data collection
Diffractometer	Rigaku AFC-8S
Absorption correction	Multi-scan (REQAB; Jacobson, 1998)
T_min, T_max	0.945, 0.977
No. of measured, independent and observed [I > 2σ(I)] reflections	6640, 3104, 2787
R_int	0.014
(sin θ/λ)_max (Å⁻¹)	0.597

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.099, 1.04
No. of reflections	3104
No. of parameters	235
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.20

Computer programs: CrystalClear (Rigaku/MSC, 2006), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4b···O1ⁱ	0.99	2.50	3.472 (2)	167.7 (1)

Symmetry code: (i) −x+1, −y+1, −z.

Acknowledgements

The authors thank the Pakistan Science Foundation for financial support.

References

Ali, Q., Ibad, F., Shah, M. R. & VanDerveer, D. (2008). Acta Cryst. E64, o1408. Web of Science CSD CrossRef IUCr Journals Google Scholar
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