3-Methyl-1-propargylquinoxalin-2(1H)-one

Benzeid, H.; Ramli, Y.; Vendier, L.; Essassi, E.M.; Ng, S.W.

doi:10.1107/S1600536809032498

organic compounds

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Page o2196

doi:10.1107/S1600536809032498

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3-Methyl-1-propargylquinoxalin-2(1H)-one

Hanane Benzeid,^a Youssef Ramli,^a Laure Vendier,^b El Mokhtar Essassi ^a and Seik Weng Ng ^c ^*

^aLaboratoire de Chimie Organique Hétérocyclique, Pôle de compétences Pharmacochimie, Université Mohammed V-Agdal, BP 1014 Avenue Ibn Batout, Rabat, Morocco, ^bLaboratoire de Chimie de Coordination, 205 Route de Narbonne, Toulouse Cedex 04, France, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 14 August 2009; accepted 16 August 2009; online 22 August 2009)

The ten-membered fused ring of the title compound, C₁₂H₁₀N₂O, is essentially planar in the two independent molecules of the asymmetric unit (r.m.s. deviations = 0.012 and 0.015 Å).

Related literature

For the crystal structure of 1-ethyl-3-methylquinoxalin-2(1H)-one, see: Benzeid et al. (2008 ). For the synthesis of the reactant 3-methyl-1H-quinoxalin-2-one, see: Nikolaenko & Munro (2004 ).

Experimental

Crystal data

C₁₂H₁₀N₂O
M_r = 198.22
Monoclinic, P 2₁ /n
a = 21.124 (1) Å
b = 4.3709 (2) Å
c = 22.246 (1) Å
β = 105.354 (6)°
V = 1980.7 (2) Å³
Z = 8
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 180 K
0.20 × 0.15 × 0.08 mm

Data collection

Oxford Diffraction Xcalibur diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.985, T_max = 0.991
14275 measured reflections
4058 independent reflections
2428 reflections with I > 2σ(I)
R_int = 0.046

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.102
S = 0.97
4058 reflections
273 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809032498/xu2590sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809032498/xu2590Isup2.hkl

checkCIF report

Related literature top

For the crystal structure of 1-ethyl-3-methylquinoxalin-2(1H)-one, see: Benzeid et al. (2008). For the synthesis of the reactant 3-methyl-1H-quinoxalin-2-one, see: Nikolaenko & Munro (2004).

Experimental top

To a solution of 3-methylquinoxalin-2(1H)-one (Nikolaenko & Munro et al., 2004) (1 g, 6.22 mmol) in DMF (20 ml) was added propargyl bromide (0.82 ml, 6.22 mmol), potassium carbonate (1 g, 7.46 mmol) and a catalytic quantity of tetra-n-butylammonium bromide. The mixture was stirred at room temperature for 24 h. The solution was filtered and the solvent removed under reduced pressure. The residue was recrystallized from ethanol to afford 3-methyl-1-(propargyl)quinoxalin-2(1H)-one as colorless crystals.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of the two independent molecules of C₁₂H₁₀N₂O at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

3-Methyl-1-propargylquinoxalin-2(1H)-one top

Crystal data top

C₁₂H₁₀N₂O	F(000) = 832
M_r = 198.22	D_x = 1.329 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 5089 reflections
a = 21.124 (1) Å	θ = 2.7–32.2°
b = 4.3709 (2) Å	µ = 0.09 mm⁻¹
c = 22.246 (1) Å	T = 180 K
β = 105.354 (6)°	Parallelepiped, yellow
V = 1980.7 (2) Å³	0.20 × 0.15 × 0.08 mm
Z = 8

Data collection top

Oxford Diffraction Xcalibur diffractometer	4058 independent reflections
Radiation source: fine-focus sealed tube	2428 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.046
ω and ϕ scans	θ_max = 26.4°, θ_min = 2.8°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	h = −22→26
T_min = 0.985, T_max = 0.991	k = −5→5
14275 measured reflections	l = −26→27

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)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.102	H-atom parameters constrained
S = 0.97	w = 1/[σ²(F_o²) + (0.0539P)²] where P = (F_o² + 2F_c²)/3
4058 reflections	(Δ/σ)_max = 0.001
273 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₁₂H₁₀N₂O	V = 1980.7 (2) Å³
M_r = 198.22	Z = 8
Monoclinic, P2₁/n	Mo Kα radiation
a = 21.124 (1) Å	µ = 0.09 mm⁻¹
b = 4.3709 (2) Å	T = 180 K
c = 22.246 (1) Å	0.20 × 0.15 × 0.08 mm
β = 105.354 (6)°

Data collection top

Oxford Diffraction Xcalibur diffractometer	4058 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	2428 reflections with I > 2σ(I)
T_min = 0.985, T_max = 0.991	R_int = 0.046
14275 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	0 restraints
wR(F²) = 0.102	H-atom parameters constrained
S = 0.97	Δρ_max = 0.19 e Å⁻³
4058 reflections	Δρ_min = −0.22 e Å⁻³
273 parameters

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

	x	y	z	U_iso*/U_eq
O1	0.30129 (6)	0.4482 (3)	0.53550 (5)	0.0423 (3)
O2	0.53899 (5)	0.4210 (3)	0.84138 (5)	0.0423 (3)
N1	0.24291 (6)	0.1336 (3)	0.46002 (5)	0.0259 (3)
N2	0.36089 (6)	−0.0417 (3)	0.43668 (6)	0.0301 (3)
N3	0.45992 (6)	0.5883 (3)	0.75752 (6)	0.0248 (3)
N4	0.40956 (6)	0.9390 (3)	0.83838 (6)	0.0299 (3)
C1	0.30011 (8)	0.2584 (4)	0.49493 (7)	0.0284 (4)
C2	0.36032 (8)	0.1492 (4)	0.48043 (7)	0.0299 (4)
C3	0.30152 (8)	−0.1552 (4)	0.40141 (7)	0.0265 (4)
C4	0.30203 (9)	−0.3586 (4)	0.35363 (7)	0.0359 (4)
H4	0.3427	−0.4141	0.3460	0.043*
C5	0.24506 (10)	−0.4804 (4)	0.31742 (8)	0.0438 (5)
H5	0.2459	−0.6193	0.2848	0.053*
C6	0.18630 (10)	−0.3990 (4)	0.32887 (8)	0.0441 (5)
H6	0.1466	−0.4833	0.3038	0.053*
C7	0.18398 (8)	−0.1987 (4)	0.37573 (8)	0.0342 (4)
H7	0.1430	−0.1453	0.3830	0.041*
C8	0.24165 (8)	−0.0749 (3)	0.41244 (7)	0.0250 (4)
C9	0.18204 (8)	0.2356 (4)	0.47433 (8)	0.0324 (4)
H9A	0.1884	0.4460	0.4914	0.039*
H9B	0.1462	0.2416	0.4353	0.039*
C10	0.16261 (7)	0.0368 (4)	0.51906 (7)	0.0285 (4)
C11	0.14630 (8)	−0.1151 (4)	0.55593 (8)	0.0356 (4)
H11	0.1331	−0.2379	0.5857	0.043*
C12	0.42291 (8)	0.2734 (5)	0.52009 (9)	0.0484 (5)
H12A	0.4594	0.2039	0.5040	0.073*
H12B	0.4294	0.2006	0.5630	0.073*
H12C	0.4212	0.4974	0.5194	0.073*
C13	0.49034 (7)	0.5800 (4)	0.81993 (7)	0.0284 (4)
C14	0.46119 (8)	0.7751 (4)	0.85929 (7)	0.0304 (4)
C15	0.37878 (7)	0.9314 (4)	0.77527 (7)	0.0248 (4)
C16	0.32214 (7)	1.1033 (4)	0.75256 (8)	0.0329 (4)
H16	0.3056	1.2241	0.7805	0.039*
C17	0.29004 (8)	1.1009 (4)	0.69069 (8)	0.0365 (4)
H17	0.2514	1.2194	0.6756	0.044*
C18	0.31410 (8)	0.9248 (4)	0.64995 (8)	0.0351 (4)
H18	0.2914	0.9213	0.6070	0.042*
C19	0.37008 (8)	0.7558 (4)	0.67064 (7)	0.0294 (4)
H19	0.3863	0.6373	0.6422	0.035*
C20	0.40306 (7)	0.7585 (3)	0.73351 (7)	0.0227 (3)
C21	0.48885 (8)	0.4108 (4)	0.71564 (7)	0.0323 (4)
H21A	0.5219	0.2677	0.7405	0.039*
H21B	0.4541	0.2881	0.6872	0.039*
C22	0.52007 (8)	0.6082 (4)	0.67891 (8)	0.0326 (4)
C23	0.54466 (9)	0.7662 (5)	0.64907 (8)	0.0429 (5)
H23	0.5646	0.8945	0.6248	0.051*
C24	0.49583 (9)	0.7818 (5)	0.92679 (8)	0.0503 (5)
H24A	0.5381	0.8860	0.9328	0.075*
H24B	0.5032	0.5719	0.9426	0.075*
H24C	0.4690	0.8918	0.9495	0.075*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0525 (8)	0.0439 (7)	0.0306 (7)	0.0029 (6)	0.0113 (6)	−0.0077 (6)
O2	0.0237 (6)	0.0535 (8)	0.0453 (7)	0.0048 (6)	0.0016 (5)	0.0074 (7)
N1	0.0248 (7)	0.0277 (7)	0.0275 (7)	0.0052 (6)	0.0108 (6)	0.0035 (6)
N2	0.0285 (8)	0.0303 (7)	0.0341 (8)	0.0050 (7)	0.0130 (6)	0.0079 (7)
N3	0.0218 (7)	0.0273 (7)	0.0259 (7)	−0.0017 (6)	0.0076 (6)	−0.0022 (6)
N4	0.0257 (8)	0.0407 (8)	0.0237 (7)	−0.0059 (7)	0.0074 (6)	−0.0041 (7)
C1	0.0349 (10)	0.0295 (9)	0.0216 (9)	0.0026 (8)	0.0089 (7)	0.0055 (8)
C2	0.0287 (9)	0.0295 (9)	0.0304 (9)	0.0024 (8)	0.0056 (7)	0.0078 (8)
C3	0.0319 (9)	0.0251 (8)	0.0248 (9)	0.0068 (8)	0.0118 (7)	0.0082 (7)
C4	0.0519 (12)	0.0287 (9)	0.0323 (10)	0.0102 (9)	0.0202 (9)	0.0063 (8)
C5	0.0722 (15)	0.0324 (10)	0.0271 (10)	0.0005 (10)	0.0133 (10)	−0.0017 (8)
C6	0.0542 (13)	0.0368 (11)	0.0324 (10)	−0.0058 (10)	−0.0041 (9)	0.0046 (9)
C7	0.0323 (10)	0.0330 (10)	0.0341 (10)	0.0008 (8)	0.0035 (8)	0.0089 (8)
C8	0.0309 (9)	0.0223 (8)	0.0228 (8)	0.0040 (8)	0.0089 (7)	0.0061 (7)
C9	0.0301 (9)	0.0324 (9)	0.0394 (10)	0.0100 (8)	0.0173 (8)	0.0052 (8)
C10	0.0227 (8)	0.0355 (9)	0.0285 (9)	0.0043 (8)	0.0086 (7)	−0.0034 (8)
C11	0.0274 (9)	0.0492 (11)	0.0323 (10)	0.0023 (9)	0.0115 (8)	0.0025 (9)
C12	0.0335 (11)	0.0510 (12)	0.0554 (12)	−0.0012 (10)	0.0023 (9)	0.0028 (10)
C13	0.0192 (8)	0.0364 (10)	0.0276 (9)	−0.0079 (8)	0.0028 (7)	0.0023 (8)
C14	0.0250 (9)	0.0424 (10)	0.0236 (9)	−0.0082 (8)	0.0064 (7)	−0.0001 (8)
C15	0.0211 (8)	0.0293 (8)	0.0251 (9)	−0.0075 (7)	0.0083 (7)	−0.0020 (7)
C16	0.0255 (9)	0.0325 (10)	0.0429 (11)	−0.0003 (8)	0.0130 (8)	−0.0012 (9)
C17	0.0232 (9)	0.0396 (11)	0.0440 (11)	0.0002 (8)	0.0041 (8)	0.0103 (9)
C18	0.0316 (10)	0.0416 (10)	0.0286 (9)	−0.0087 (9)	0.0017 (8)	0.0076 (9)
C19	0.0289 (9)	0.0354 (9)	0.0237 (9)	−0.0068 (8)	0.0067 (7)	−0.0012 (8)
C20	0.0177 (8)	0.0248 (8)	0.0253 (8)	−0.0055 (7)	0.0052 (6)	0.0010 (7)
C21	0.0355 (9)	0.0298 (9)	0.0347 (9)	0.0001 (8)	0.0144 (8)	−0.0050 (8)
C22	0.0273 (9)	0.0364 (10)	0.0374 (10)	0.0010 (8)	0.0144 (8)	−0.0074 (8)
C23	0.0389 (11)	0.0477 (11)	0.0493 (11)	0.0020 (9)	0.0244 (9)	−0.0007 (10)
C24	0.0372 (11)	0.0816 (15)	0.0279 (10)	−0.0060 (11)	0.0014 (8)	−0.0031 (10)

Geometric parameters (Å, º) top

O1—C1	1.2213 (18)	C9—H9B	0.9900
O2—C13	1.2277 (18)	C10—C11	1.176 (2)
N1—C1	1.365 (2)	C11—H11	0.9500
N1—C8	1.3917 (19)	C12—H12A	0.9800
N1—C9	1.4732 (19)	C12—H12B	0.9800
N2—C2	1.285 (2)	C12—H12C	0.9800
N2—C3	1.383 (2)	C13—C14	1.469 (2)
N3—C13	1.3673 (19)	C14—C24	1.486 (2)
N3—C20	1.3934 (19)	C15—C16	1.390 (2)
N3—C21	1.4643 (19)	C15—C20	1.396 (2)
N4—C14	1.285 (2)	C16—C17	1.364 (2)
N4—C15	1.3826 (18)	C16—H16	0.9500
C1—C2	1.472 (2)	C17—C18	1.384 (2)
C2—C12	1.484 (2)	C17—H17	0.9500
C3—C4	1.388 (2)	C18—C19	1.367 (2)
C3—C8	1.395 (2)	C18—H18	0.9500
C4—C5	1.367 (2)	C19—C20	1.388 (2)
C4—H4	0.9500	C19—H19	0.9500
C5—C6	1.378 (3)	C21—C22	1.460 (2)
C5—H5	0.9500	C21—H21A	0.9900
C6—C7	1.372 (2)	C21—H21B	0.9900
C6—H6	0.9500	C22—C23	1.171 (2)
C7—C8	1.385 (2)	C23—H23	0.9500
C7—H7	0.9500	C24—H24A	0.9800
C9—C10	1.459 (2)	C24—H24B	0.9800
C9—H9A	0.9900	C24—H24C	0.9800

C1—N1—C8	122.01 (13)	H12A—C12—H12B	109.5
C1—N1—C9	116.60 (13)	C2—C12—H12C	109.5
C8—N1—C9	121.38 (13)	H12A—C12—H12C	109.5
C2—N2—C3	118.28 (14)	H12B—C12—H12C	109.5
C13—N3—C20	121.95 (13)	O2—C13—N3	121.98 (15)
C13—N3—C21	117.96 (13)	O2—C13—C14	122.47 (15)
C20—N3—C21	120.10 (13)	N3—C13—C14	115.55 (14)
C14—N4—C15	118.69 (14)	N4—C14—C13	123.89 (15)
O1—C1—N1	122.25 (15)	N4—C14—C24	119.90 (16)
O1—C1—C2	122.16 (16)	C13—C14—C24	116.20 (15)
N1—C1—C2	115.59 (14)	N4—C15—C16	118.96 (14)
N2—C2—C1	123.96 (15)	N4—C15—C20	122.13 (14)
N2—C2—C12	120.14 (15)	C16—C15—C20	118.91 (14)
C1—C2—C12	115.90 (15)	C17—C16—C15	120.85 (16)
N2—C3—C4	118.32 (15)	C17—C16—H16	119.6
N2—C3—C8	122.53 (14)	C15—C16—H16	119.6
C4—C3—C8	119.15 (16)	C16—C17—C18	119.63 (16)
C5—C4—C3	121.12 (17)	C16—C17—H17	120.2
C5—C4—H4	119.4	C18—C17—H17	120.2
C3—C4—H4	119.4	C19—C18—C17	120.99 (16)
C4—C5—C6	119.08 (17)	C19—C18—H18	119.5
C4—C5—H5	120.5	C17—C18—H18	119.5
C6—C5—H5	120.5	C18—C19—C20	119.59 (16)
C7—C6—C5	121.35 (17)	C18—C19—H19	120.2
C7—C6—H6	119.3	C20—C19—H19	120.2
C5—C6—H6	119.3	C19—C20—N3	122.26 (14)
C6—C7—C8	119.64 (17)	C19—C20—C15	120.01 (14)
C6—C7—H7	120.2	N3—C20—C15	117.72 (13)
C8—C7—H7	120.2	C22—C21—N3	111.69 (13)
C7—C8—N1	122.76 (14)	C22—C21—H21A	109.3
C7—C8—C3	119.66 (15)	N3—C21—H21A	109.3
N1—C8—C3	117.57 (14)	C22—C21—H21B	109.3
C10—C9—N1	112.71 (13)	N3—C21—H21B	109.3
C10—C9—H9A	109.1	H21A—C21—H21B	107.9
N1—C9—H9A	109.1	C23—C22—C21	179.5 (2)
C10—C9—H9B	109.1	C22—C23—H23	180.0
N1—C9—H9B	109.1	C14—C24—H24A	109.5
H9A—C9—H9B	107.8	C14—C24—H24B	109.5
C11—C10—C9	177.82 (17)	H24A—C24—H24B	109.5
C10—C11—H11	180.0	C14—C24—H24C	109.5
C2—C12—H12A	109.5	H24A—C24—H24C	109.5
C2—C12—H12B	109.5	H24B—C24—H24C	109.5

C8—N1—C1—O1	177.78 (14)	C20—N3—C13—O2	177.17 (14)
C9—N1—C1—O1	−1.0 (2)	C21—N3—C13—O2	−2.8 (2)
C8—N1—C1—C2	−2.2 (2)	C20—N3—C13—C14	−3.2 (2)
C9—N1—C1—C2	179.07 (12)	C21—N3—C13—C14	176.86 (13)
C3—N2—C2—C1	−0.8 (2)	C15—N4—C14—C13	0.6 (2)
C3—N2—C2—C12	179.06 (15)	C15—N4—C14—C24	179.19 (15)
O1—C1—C2—N2	−177.42 (15)	O2—C13—C14—N4	−178.51 (16)
N1—C1—C2—N2	2.6 (2)	N3—C13—C14—N4	1.9 (2)
O1—C1—C2—C12	2.7 (2)	O2—C13—C14—C24	2.9 (2)
N1—C1—C2—C12	−177.34 (14)	N3—C13—C14—C24	−176.77 (15)
C2—N2—C3—C4	179.21 (13)	C14—N4—C15—C16	178.69 (15)
C2—N2—C3—C8	−1.3 (2)	C14—N4—C15—C20	−1.9 (2)
N2—C3—C4—C5	179.55 (15)	N4—C15—C16—C17	−179.62 (15)
C8—C3—C4—C5	0.0 (2)	C20—C15—C16—C17	0.9 (2)
C3—C4—C5—C6	−0.1 (2)	C15—C16—C17—C18	0.1 (3)
C4—C5—C6—C7	0.0 (3)	C16—C17—C18—C19	−0.8 (3)
C5—C6—C7—C8	0.0 (2)	C17—C18—C19—C20	0.6 (2)
C6—C7—C8—N1	178.84 (14)	C18—C19—C20—N3	179.23 (14)
C6—C7—C8—C3	0.0 (2)	C18—C19—C20—C15	0.4 (2)
C1—N1—C8—C7	−178.59 (15)	C13—N3—C20—C19	−176.69 (14)
C9—N1—C8—C7	0.1 (2)	C21—N3—C20—C19	3.2 (2)
C1—N1—C8—C3	0.3 (2)	C13—N3—C20—C15	2.1 (2)
C9—N1—C8—C3	178.99 (13)	C21—N3—C20—C15	−177.94 (13)
N2—C3—C8—C7	−179.48 (14)	N4—C15—C20—C19	179.38 (14)
C4—C3—C8—C7	0.0 (2)	C16—C15—C20—C19	−1.2 (2)
N2—C3—C8—N1	1.6 (2)	N4—C15—C20—N3	0.5 (2)
C4—C3—C8—N1	−178.93 (13)	C16—C15—C20—N3	180.00 (14)
C1—N1—C9—C10	−93.04 (17)	C13—N3—C21—C22	−107.74 (16)
C8—N1—C9—C10	88.22 (17)	C20—N3—C21—C22	72.32 (18)

Experimental details

Crystal data
Chemical formula	C₁₂H₁₀N₂O
M_r	198.22
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	180
a, b, c (Å)	21.124 (1), 4.3709 (2), 22.246 (1)
β (°)	105.354 (6)
V (Å³)	1980.7 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.20 × 0.15 × 0.08

Data collection
Diffractometer	Oxford Diffraction Xcalibur diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.985, 0.991
No. of measured, independent and observed [I > 2σ(I)] reflections	14275, 4058, 2428
R_int	0.046
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.102, 0.97
No. of reflections	4058
No. of parameters	273
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.22

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

Acknowledgements

We thank Université Mohammed V-Agdal and the University of Malaya for supporting this study.

References

Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Benzeid, H., Vendier, L., Ramli, Y., Garrigues, B. & Essassi, E. M. (2008). Acta Cryst. E64, o2234. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2009). publCIF. In preparation. Google Scholar