6-Bromo-1,3-dimethyl-1H-imidazo[4,5-b]pyridin-2(3H)-one

Dahmani, S.; Rodi, Y.K.; Zouihri, H.; Essassi, E.M.; Ng, S.W.

doi:10.1107/S1600536810025134

organic compounds

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ISSN: 2056-9890

Volume 66| Part 8| August 2010| Page o1904

https://doi.org/10.1107/S1600536810025134

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6-Bromo-1,3-dimethyl-1H-imidazo[4,5-b]pyridin-2(3H)-one

Siham Dahmani,^a Youssef Kandri Rodi,^a Hafid Zouihri,^b El Mokhtar Essassi ^c and Seik Weng Ng ^d ^*

^aLaboratoire de Chimie Organique Appliquée, Faculté des Sciences et Techniques, Université Sidi Mohamed Ben Abdallah, Fès, Morocco, ^bCNRST Division UATRS, Angle Allal Fassi/FAR, BP 8027 Hay Riad, Rabat, Morocco, ^cLaboratoire de Chimie Organique Hétérocyclique, Pôle de Compétences Pharmacochimie, Université Mohammed V-Agdal, BP 1014 Avenue Ibn Batout, Rabat, Morocco, and ^dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 24 June 2010; accepted 26 June 2010; online 3 July 2010)

The non-H atoms of the two independent molecules in the asymmetric unit of the title compound, C₈H₈BrN₃O, are planar (r.m.s. deviations = 0.015 and 0.019 Å). In the crystal, the molecules are linked into a zigzag chain along the c axis by C—H⋯O hydrogen bonds.

Related literature

For the synthesis of the un-brominated compound, see: Yutilov et al. (1998 , 2005 ).

Experimental

Crystal data

C₈H₈BrN₃O
M_r = 242.08
Monoclinic, P 2₁ /c
a = 21.7981 (4) Å
b = 3.9929 (1) Å
c = 20.6636 (3) Å
β = 95.398 (1)°
V = 1790.53 (6) Å³
Z = 8
Mo Kα radiation
μ = 4.55 mm⁻¹
T = 293 K
0.25 × 0.20 × 0.15 mm

Data collection

Bruker X8 APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.396, T_max = 0.548
21586 measured reflections
5229 independent reflections
3539 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.031
wR(F²) = 0.086
S = 1.01
5229 reflections
239 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8C⋯O2ⁱ	0.96	2.33	3.279 (3)	167
C11—H11⋯O1	0.93	2.49	3.321 (3)	148
Symmetry code: (i) $[x, -y+{\script{5\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; 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, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810025134/ci5119sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810025134/ci5119Isup2.hkl

checkCIF report

Comment top

The imidazo[4,5-b]pyridine unit is an important heterocyclic nucleus found in a large number of medicinal compounds. The synthesis of 1,3-dimethyl-1,3-dihydro-imidazo[4,5-b]pyridin-2-one involves several steps (Yutilov et al., 1998, 2005). The 6-bromo derivative (Scheme I) is conveniently synthesized by the direct reaction of 6-bromo-1,3-dihydro-imidazo[4,5-b]pyridin-2-one with methyl iodide.

The aysmmetric unit (Fig. 1) has two independent molecules. Both are planar.

Related literature top

For the synthesis of the un-brominated compound, see: Yutilov et al. (1998, 2005).

Experimental top

To a mixture of 6-bromo-1,3-dihydro-imidazo[4,5-b]pyridin-2-one (0.15 g, 1 mmol), potassium carbonate (0.38 g, 4 mmol) and tetra-n-butylammonium bromide (0.02 g, 0.1 mmol) in DMF (10 ml) was added methyl iodide (0.1 ml, 2.5 mmol). Stirring was continued at room temperature for 12 h. After the completion of reaction (as monitored by TLC), the mixture was filtered and the solvent removed under reduced pressure. The residue was purified by column chromatography on silica gel with ethyl acetate-hexane (1:3) as eluent. The compound was recrystallized from ethyl acetate-hexane (1:3) to afford colourless crystals.

Structure description top

The aysmmetric unit (Fig. 1) has two independent molecules. Both are planar.

For the synthesis of the un-brominated compound, see: Yutilov et al. (1998, 2005).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); 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, 2010).

Figures top

Fig. 1. Displacement ellipsoid plot (Barbour, 2001) of the two independent molecules of C₈H₈BrN₃O at the 50% probability level. H atoms are shown as spheres of arbitrary radii.

6-Bromo-1,3-dimethyl-1H-imidazo[4,5-b]pyridin-2(3H)-one top

Crystal data top

C₈H₈BrN₃O	F(000) = 960
M_r = 242.08	D_x = 1.796 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6375 reflections
a = 21.7981 (4) Å	θ = 2.6–25.2°
b = 3.9929 (1) Å	µ = 4.55 mm⁻¹
c = 20.6636 (3) Å	T = 293 K
β = 95.398 (1)°	Prism, colourless
V = 1790.53 (6) Å³	0.25 × 0.20 × 0.15 mm
Z = 8

Data collection top

Bruker X8 APEXII area-detector diffractometer	5229 independent reflections
Radiation source: fine-focus sealed tube	3539 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
φ and ω scans	θ_max = 30.0°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −30→28
T_min = 0.396, T_max = 0.548	k = −5→5
21586 measured reflections	l = −29→28

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)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.086	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0438P)² + 0.1144P] where P = (F_o² + 2F_c²)/3
5229 reflections	(Δ/σ)_max = 0.001
239 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

C₈H₈BrN₃O	V = 1790.53 (6) Å³
M_r = 242.08	Z = 8
Monoclinic, P2₁/c	Mo Kα radiation
a = 21.7981 (4) Å	µ = 4.55 mm⁻¹
b = 3.9929 (1) Å	T = 293 K
c = 20.6636 (3) Å	0.25 × 0.20 × 0.15 mm
β = 95.398 (1)°

Data collection top

Bruker X8 APEXII area-detector diffractometer	5229 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3539 reflections with I > 2σ(I)
T_min = 0.396, T_max = 0.548	R_int = 0.036
21586 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.031	0 restraints
wR(F²) = 0.086	H-atom parameters constrained
S = 1.01	Δρ_max = 0.28 e Å⁻³
5229 reflections	Δρ_min = −0.29 e Å⁻³
239 parameters

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

	x	y	z	U_iso*/U_eq
Br1	0.407800 (11)	0.91753 (7)	0.468246 (11)	0.05023 (9)
N1	0.44555 (8)	0.5071 (5)	0.65032 (9)	0.0416 (4)
N2	0.37942 (8)	0.4903 (5)	0.73723 (8)	0.0400 (4)
N3	0.29799 (8)	0.7480 (5)	0.68786 (8)	0.0387 (4)
N4	0.05385 (8)	0.5642 (5)	0.92033 (9)	0.0400 (4)
N5	0.12070 (8)	0.8692 (5)	0.99889 (8)	0.0391 (4)
N6	0.19961 (8)	0.9449 (5)	0.94033 (8)	0.0373 (4)
O1	0.29345 (8)	0.5668 (5)	0.79455 (8)	0.0568 (5)
O2	0.20597 (8)	1.1650 (5)	1.04514 (8)	0.0576 (5)
C1	0.44708 (10)	0.6147 (6)	0.58839 (11)	0.0421 (5)
H1	0.4826	0.5767	0.5678	0.050*
C2	0.39881 (10)	0.7769 (6)	0.55465 (10)	0.0374 (5)
C3	0.34349 (10)	0.8436 (5)	0.58128 (10)	0.0356 (5)
H3	0.3105	0.9528	0.5585	0.043*
C4	0.34205 (9)	0.7335 (5)	0.64419 (10)	0.0339 (4)
C5	0.39361 (9)	0.5704 (5)	0.67562 (10)	0.0345 (5)
C6	0.42023 (12)	0.3314 (7)	0.78847 (13)	0.0546 (7)
H6A	0.3960	0.2231	0.8188	0.082*
H6B	0.4460	0.4983	0.8107	0.082*
H6C	0.4455	0.1684	0.7696	0.082*
C7	0.32072 (10)	0.5976 (6)	0.74587 (11)	0.0411 (5)
C8	0.23694 (10)	0.8923 (7)	0.67783 (13)	0.0503 (6)
H8A	0.2289	1.0214	0.7153	0.075*
H8B	0.2070	0.7164	0.6713	0.075*
H8C	0.2344	1.0348	0.6402	0.075*
C9	0.05044 (10)	0.4500 (6)	0.85870 (11)	0.0415 (5)
H9	0.0149	0.3385	0.8423	0.050*
C10	0.09723 (10)	0.4905 (5)	0.81873 (10)	0.0356 (5)
C11	0.15197 (9)	0.6529 (5)	0.83943 (10)	0.0350 (5)
H11	0.1839	0.6795	0.8130	0.042*
C12	0.15516 (9)	0.7711 (5)	0.90210 (9)	0.0311 (4)
C13	0.10513 (9)	0.7226 (5)	0.93943 (10)	0.0337 (4)
C14	0.08264 (13)	0.8834 (8)	1.05313 (13)	0.0621 (8)
H14A	0.1083	0.8604	1.0933	0.093*
H14B	0.0530	0.7048	1.0492	0.093*
H14C	0.0615	1.0945	1.0526	0.093*
C15	0.17830 (10)	1.0112 (6)	0.99985 (11)	0.0408 (5)
C16	0.25863 (10)	1.0616 (6)	0.92138 (12)	0.0474 (6)
H16A	0.2842	1.1318	0.9593	0.071*
H16B	0.2520	1.2468	0.8919	0.071*
H16C	0.2786	0.8829	0.9004	0.071*
Br2	0.086179 (12)	0.32023 (7)	0.732957 (11)	0.05183 (9)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.05040 (16)	0.06094 (17)	0.04140 (14)	−0.00344 (12)	0.01514 (11)	0.00544 (11)
N1	0.0294 (9)	0.0492 (12)	0.0453 (11)	0.0036 (8)	−0.0008 (8)	−0.0047 (8)
N2	0.0366 (10)	0.0488 (12)	0.0335 (10)	0.0022 (8)	−0.0025 (8)	0.0032 (8)
N3	0.0332 (10)	0.0493 (11)	0.0343 (9)	0.0062 (8)	0.0063 (7)	0.0052 (8)
N4	0.0318 (10)	0.0484 (11)	0.0403 (10)	−0.0036 (8)	0.0061 (8)	0.0035 (8)
N5	0.0396 (10)	0.0478 (11)	0.0306 (9)	0.0006 (8)	0.0071 (8)	−0.0029 (8)
N6	0.0332 (9)	0.0425 (10)	0.0357 (9)	−0.0038 (8)	0.0012 (7)	0.0002 (8)
O1	0.0547 (10)	0.0782 (13)	0.0395 (9)	0.0077 (9)	0.0152 (8)	0.0125 (8)
O2	0.0627 (12)	0.0644 (12)	0.0439 (10)	−0.0092 (9)	−0.0042 (9)	−0.0157 (8)
C1	0.0303 (11)	0.0507 (14)	0.0463 (13)	−0.0013 (10)	0.0096 (10)	−0.0058 (10)
C2	0.0362 (12)	0.0429 (12)	0.0337 (11)	−0.0065 (10)	0.0069 (9)	−0.0025 (9)
C3	0.0322 (11)	0.0394 (12)	0.0350 (11)	0.0000 (9)	0.0015 (9)	0.0010 (8)
C4	0.0289 (11)	0.0356 (11)	0.0373 (11)	−0.0003 (9)	0.0045 (8)	−0.0016 (9)
C5	0.0332 (11)	0.0370 (11)	0.0322 (11)	−0.0027 (9)	−0.0028 (8)	−0.0038 (8)
C6	0.0565 (16)	0.0608 (17)	0.0441 (13)	0.0095 (13)	−0.0084 (11)	0.0098 (12)
C7	0.0400 (12)	0.0477 (13)	0.0357 (12)	0.0000 (10)	0.0041 (9)	0.0006 (9)
C8	0.0385 (13)	0.0615 (16)	0.0520 (14)	0.0104 (11)	0.0101 (11)	0.0106 (12)
C9	0.0333 (12)	0.0433 (13)	0.0463 (13)	−0.0043 (10)	−0.0046 (10)	0.0021 (10)
C10	0.0405 (12)	0.0358 (12)	0.0295 (10)	0.0029 (9)	−0.0013 (9)	0.0024 (8)
C11	0.0338 (11)	0.0393 (12)	0.0321 (11)	0.0031 (9)	0.0048 (8)	0.0051 (8)
C12	0.0293 (10)	0.0320 (11)	0.0318 (10)	0.0012 (8)	0.0013 (8)	0.0039 (8)
C13	0.0321 (11)	0.0362 (11)	0.0327 (10)	0.0040 (9)	0.0028 (8)	0.0046 (8)
C14	0.0624 (17)	0.082 (2)	0.0457 (14)	−0.0051 (15)	0.0220 (13)	−0.0141 (13)
C15	0.0435 (13)	0.0423 (13)	0.0357 (11)	0.0036 (10)	−0.0010 (10)	0.0011 (9)
C16	0.0336 (12)	0.0531 (14)	0.0557 (15)	−0.0068 (11)	0.0049 (10)	0.0010 (11)
Br2	0.06391 (18)	0.05326 (16)	0.03660 (13)	−0.00056 (12)	−0.00434 (11)	−0.00705 (10)

Geometric parameters (Å, º) top

Br1—C2	1.899 (2)	C3—C4	1.375 (3)
N1—C5	1.316 (3)	C3—H3	0.93
N1—C1	1.353 (3)	C4—C5	1.404 (3)
N2—C5	1.376 (3)	C6—H6A	0.96
N2—C7	1.377 (3)	C6—H6B	0.96
N2—C6	1.462 (3)	C6—H6C	0.96
N3—C4	1.380 (3)	C8—H8A	0.96
N3—C7	1.390 (3)	C8—H8B	0.96
N3—C8	1.447 (3)	C8—H8C	0.96
N4—C13	1.313 (3)	C9—C10	1.381 (3)
N4—C9	1.348 (3)	C9—H9	0.93
N5—C13	1.374 (3)	C10—C11	1.390 (3)
N5—C15	1.376 (3)	C10—Br2	1.893 (2)
N5—C14	1.457 (3)	C11—C12	1.374 (3)
N6—C12	1.379 (3)	C11—H11	0.93
N6—C15	1.381 (3)	C12—C13	1.407 (3)
N6—C16	1.456 (3)	C14—H14A	0.96
O1—C7	1.222 (3)	C14—H14B	0.96
O2—C15	1.229 (3)	C14—H14C	0.96
C1—C2	1.369 (3)	C16—H16A	0.96
C1—H1	0.93	C16—H16B	0.96
C2—C3	1.397 (3)	C16—H16C	0.96

C5—N1—C1	114.43 (18)	N2—C7—N3	106.43 (18)
C5—N2—C7	109.90 (17)	N3—C8—H8A	109.5
C5—N2—C6	126.63 (19)	N3—C8—H8B	109.5
C7—N2—C6	123.40 (19)	H8A—C8—H8B	109.5
C4—N3—C7	109.41 (18)	N3—C8—H8C	109.5
C4—N3—C8	127.62 (19)	H8A—C8—H8C	109.5
C7—N3—C8	122.96 (19)	H8B—C8—H8C	109.5
C13—N4—C9	114.63 (18)	N4—C9—C10	123.2 (2)
C13—N5—C15	109.67 (18)	N4—C9—H9	118.4
C13—N5—C14	126.4 (2)	C10—C9—H9	118.4
C15—N5—C14	123.9 (2)	C9—C10—C11	122.1 (2)
C12—N6—C15	109.26 (17)	C9—C10—Br2	118.81 (16)
C12—N6—C16	126.73 (18)	C11—C10—Br2	119.06 (16)
C15—N6—C16	123.92 (19)	C12—C11—C10	114.59 (19)
N1—C1—C2	123.1 (2)	C12—C11—H11	122.7
N1—C1—H1	118.5	C10—C11—H11	122.7
C2—C1—H1	118.5	N6—C12—C11	133.1 (2)
C1—C2—C3	122.7 (2)	N6—C12—C13	107.11 (17)
C1—C2—Br1	118.44 (16)	C11—C12—C13	119.8 (2)
C3—C2—Br1	118.88 (16)	N4—C13—N5	127.28 (19)
C4—C3—C2	114.1 (2)	N4—C13—C12	125.70 (19)
C4—C3—H3	122.9	N5—C13—C12	107.02 (18)
C2—C3—H3	122.9	N5—C14—H14A	109.5
C3—C4—N3	133.2 (2)	N5—C14—H14B	109.5
C3—C4—C5	119.79 (19)	H14A—C14—H14B	109.5
N3—C4—C5	107.04 (18)	N5—C14—H14C	109.5
N1—C5—N2	126.9 (2)	H14A—C14—H14C	109.5
N1—C5—C4	125.9 (2)	H14B—C14—H14C	109.5
N2—C5—C4	107.22 (18)	O2—C15—N6	126.3 (2)
N2—C6—H6A	109.5	O2—C15—N5	126.8 (2)
N2—C6—H6B	109.5	N6—C15—N5	106.92 (18)
H6A—C6—H6B	109.5	N6—C16—H16A	109.5
N2—C6—H6C	109.5	N6—C16—H16B	109.5
H6A—C6—H6C	109.5	H16A—C16—H16B	109.5
H6B—C6—H6C	109.5	N6—C16—H16C	109.5
O1—C7—N2	127.3 (2)	H16A—C16—H16C	109.5
O1—C7—N3	126.3 (2)	H16B—C16—H16C	109.5

C5—N1—C1—C2	0.2 (3)	C13—N4—C9—C10	0.9 (3)
N1—C1—C2—C3	−0.4 (4)	N4—C9—C10—C11	0.2 (3)
N1—C1—C2—Br1	179.39 (17)	N4—C9—C10—Br2	−179.59 (17)
C1—C2—C3—C4	0.3 (3)	C9—C10—C11—C12	−0.6 (3)
Br1—C2—C3—C4	−179.52 (15)	Br2—C10—C11—C12	179.19 (15)
C2—C3—C4—N3	179.6 (2)	C15—N6—C12—C11	178.1 (2)
C2—C3—C4—C5	0.0 (3)	C16—N6—C12—C11	1.5 (4)
C7—N3—C4—C3	−179.7 (2)	C15—N6—C12—C13	−1.1 (2)
C8—N3—C4—C3	0.5 (4)	C16—N6—C12—C13	−177.7 (2)
C7—N3—C4—C5	−0.1 (2)	C10—C11—C12—N6	−179.2 (2)
C8—N3—C4—C5	−179.9 (2)	C10—C11—C12—C13	−0.1 (3)
C1—N1—C5—N2	−179.9 (2)	C9—N4—C13—N5	178.9 (2)
C1—N1—C5—C4	0.1 (3)	C9—N4—C13—C12	−1.7 (3)
C7—N2—C5—N1	180.0 (2)	C15—N5—C13—N4	−179.7 (2)
C6—N2—C5—N1	3.0 (4)	C14—N5—C13—N4	−1.1 (4)
C7—N2—C5—C4	−0.1 (2)	C15—N5—C13—C12	0.8 (2)
C6—N2—C5—C4	−177.1 (2)	C14—N5—C13—C12	179.4 (2)
C3—C4—C5—N1	−0.3 (3)	N6—C12—C13—N4	−179.3 (2)
N3—C4—C5—N1	−180.0 (2)	C11—C12—C13—N4	1.4 (3)
C3—C4—C5—N2	179.80 (19)	N6—C12—C13—N5	0.2 (2)
N3—C4—C5—N2	0.1 (2)	C11—C12—C13—N5	−179.13 (19)
C5—N2—C7—O1	179.8 (2)	C12—N6—C15—O2	−179.2 (2)
C6—N2—C7—O1	−3.1 (4)	C16—N6—C15—O2	−2.4 (4)
C5—N2—C7—N3	0.1 (3)	C12—N6—C15—N5	1.5 (2)
C6—N2—C7—N3	177.2 (2)	C16—N6—C15—N5	178.30 (19)
C4—N3—C7—O1	−179.7 (2)	C13—N5—C15—O2	179.3 (2)
C8—N3—C7—O1	0.1 (4)	C14—N5—C15—O2	0.6 (4)
C4—N3—C7—N2	0.0 (3)	C13—N5—C15—N6	−1.4 (2)
C8—N3—C7—N2	179.8 (2)	C14—N5—C15—N6	179.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8C···O2ⁱ	0.96	2.33	3.279 (3)	167
C11—H11···O1	0.93	2.49	3.321 (3)	148

Symmetry code: (i) x, −y+5/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₈H₈BrN₃O
M_r	242.08
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	21.7981 (4), 3.9929 (1), 20.6636 (3)
β (°)	95.398 (1)
V (Å³)	1790.53 (6)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	4.55
Crystal size (mm)	0.25 × 0.20 × 0.15

Data collection
Diffractometer	Bruker X8 APEXII area-detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.396, 0.548
No. of measured, independent and observed [I > 2σ(I)] reflections	21586, 5229, 3539
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.086, 1.01
No. of reflections	5229
No. of parameters	239
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.29

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8C···O2ⁱ	0.96	2.33	3.279 (3)	167
C11—H11···O1	0.93	2.49	3.321 (3)	148

Symmetry code: (i) x, −y+5/2, z−1/2.

Acknowledgements

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

References

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