1-[2-(2-Oxo-1,3-oxazolidin-3-yl)eth­yl]-4-phenyl-1H-1,5-benzodiazepin-2(3H)-one

Ballo, D.; Ahabchane, N.H.; Zouihri, H.; Essassi, E.M.; Ng, S.W.

doi:10.1107/S160053681002828X

organic compounds

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ISSN: 2056-9890

Volume 66| Part 8| August 2010| Page o2080

https://doi.org/10.1107/S160053681002828X

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1-[2-(2-Oxo-1,3-oxazolidin-3-yl)ethyl]-4-phenyl-1H-1,5-benzodiazepin-2(3H)-one

Daouda Ballo,^a Noureddine Hamou Ahabchane,^a Hafid Zouihri,^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, ^bCNRST Division UATRS, Angle Allal Fassi/FAR, BP 8027 Hay Riad, Rabat, Morocco, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 7 July 2010; accepted 15 July 2010; online 21 July 2010)

The seven-membered ring in the title compound, C₂₀H₁₉N₃O₃, adopts a boat conformation with the two phenylene C atoms representing the stern and the methylene C atom the prow. The dihedral angle between the best plane through the seven-membered ring (r.m.s deviation = 0.358 Å) and the phenyl substituent is 55.8 (1)°. The two rings at either ends of the ethyl chain are staggered [N—CH₂—CH₂—N torsion angle = 57.5 (4)°].

Related literature

For the background to 2,3-dihydro-1H-1,5-benzodiazepin-2-ones, see: Ahabchane et al. (1999 ). For a related structure, see: Ballo et al. (2010 ).

Experimental

Crystal data

C₂₀H₁₉N₃O₃
M_r = 349.38
Orthorhombic, P 2₁ 2₁ 2₁
a = 9.0163 (5) Å
b = 11.6671 (6) Å
c = 16.2019 (8) Å
V = 1704.34 (15) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.25 × 0.25 × 0.15 mm

Data collection

Bruker X8 APEXII diffractometer
9253 measured reflections
2053 independent reflections
1578 reflections with I > 2σ(I)
R_int = 0.039

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.102
S = 0.90
2053 reflections
235 parameters
H-atom parameters constrained
Δρ_max = 0.12 e Å⁻³
Δρ_min = −0.16 e Å⁻³

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/S160053681002828X/zs2052sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681002828X/zs2052Isup2.hkl

checkCIF report

Comment top

The background to the class of 2,3-dihydro-1H-1,5-benzodiazepin-2-ones is given in an earlier report (Ahabchane et al., 1999). A recent study presented the crystal structure of 1-allyl-4-phenyl-2,3-dihydro-1H-1,5-benzodiazepin-2-one (Ballo et al., 2010). The present study has an oxazolidin-2-onyl-ethyl group in place of the allyl group (Scheme I, Fig. 1). The principal feature is the seven-membered ring that is fused to a phenylene ring and adopts a boat-shaped conformation, two phenylene carbons representing the stern and the methylene carbon atom the prow [r.m.s deviation 0.358 Å]. The methyl carbon deviates by 0.637 Å from the best plane. The two rings at either end of the ethyl chain are staggered [N–CH₂–CH₂–N torsion angle, 57.5 (4)°].

Related literature top

For the background to 2,3-dihydro-1H-1,5-benzodiazepin-2-ones, see: Ahabchane et al. (1999). For a related structure, see: Ballo et al. (2010).

Experimental top

To a solution of 4-phenyl-1H-1,5-benzodiazepin-2-one (2 g, 8,.4 mmol) in DMF (40 ml) was added dichloroethylamine hydrochloride (0.9 g, 8.4 mmol), potassium carbonate (3 g, 22.2 mmol) and a catalytic quantity of tetra-n-butylammonium bromide. The mixture was heated on a sand bath, the reaction monotired by thin layer chromatography. On completion of the reaction, the solvent was evaporated under reduced pressure. The residue was recrystallized from ethanol to afford the title compound as colorless crystals.

Structure description top

For the background to 2,3-dihydro-1H-1,5-benzodiazepin-2-ones, see: Ahabchane et al. (1999). For a related structure, see: Ballo et al. (2010).

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. Thermal ellipsoid plot (Barbour, 2001) of the molecule of C₂₀H₁₉N₃O₃ at the 50% probability level.

1-[2-(2-Oxo-1,3-oxazolidin-3-yl)ethyl]-4-phenyl-1H- 1,5-benzodiazepin-2(3H)-one top

Crystal data top

C₂₀H₁₉N₃O₃	F(000) = 736
M_r = 349.38	D_x = 1.362 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2227 reflections
a = 9.0163 (5) Å	θ = 2.9–21.0°
b = 11.6671 (6) Å	µ = 0.09 mm⁻¹
c = 16.2019 (8) Å	T = 293 K
V = 1704.34 (15) Å³	Prism, colorless
Z = 4	0.25 × 0.25 × 0.15 mm

Data collection top

Bruker X8 APEXII diffractometer	1578 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.039
Graphite monochromator	θ_max = 26.7°, θ_min = 2.9°
φ and ω scans	h = −11→10
9253 measured reflections	k = −14→13
2053 independent reflections	l = −20→14

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 = 0.90	w = 1/[σ²(F_o²) + (0.0742P)²] where P = (F_o² + 2F_c²)/3
2053 reflections	(Δ/σ)_max = 0.001
235 parameters	Δρ_max = 0.12 e Å⁻³
0 restraints	Δρ_min = −0.16 e Å⁻³

Crystal data top

C₂₀H₁₉N₃O₃	V = 1704.34 (15) Å³
M_r = 349.38	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 9.0163 (5) Å	µ = 0.09 mm⁻¹
b = 11.6671 (6) Å	T = 293 K
c = 16.2019 (8) Å	0.25 × 0.25 × 0.15 mm

Data collection top

Bruker X8 APEXII diffractometer	1578 reflections with I > 2σ(I)
9253 measured reflections	R_int = 0.039
2053 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	0 restraints
wR(F²) = 0.102	H-atom parameters constrained
S = 0.90	Δρ_max = 0.12 e Å⁻³
2053 reflections	Δρ_min = −0.16 e Å⁻³
235 parameters

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

	x	y	z	U_iso*/U_eq
N1	0.3905 (2)	0.62919 (16)	0.33575 (12)	0.0439 (5)
N2	0.1611 (2)	0.45822 (16)	0.37488 (12)	0.0416 (5)
N3	0.4287 (2)	0.61202 (17)	0.51545 (12)	0.0458 (5)
O1	0.5951 (2)	0.51620 (17)	0.32572 (12)	0.0669 (5)
O2	0.1947 (2)	0.60716 (17)	0.57036 (13)	0.0677 (6)
O3	0.3700 (2)	0.48444 (16)	0.61065 (11)	0.0629 (5)
C1	0.2372 (3)	0.6471 (2)	0.31906 (14)	0.0434 (5)
C2	0.1935 (3)	0.7508 (2)	0.28491 (17)	0.0597 (7)
H2	0.2650	0.8049	0.2710	0.072*
C3	0.0461 (4)	0.7750 (2)	0.27117 (19)	0.0697 (8)
H3	0.0181	0.8445	0.2477	0.084*
C4	−0.0596 (3)	0.6950 (3)	0.29269 (17)	0.0646 (8)
H4	−0.1594	0.7110	0.2841	0.078*
C5	−0.0192 (3)	0.5927 (2)	0.32647 (15)	0.0520 (6)
H5	−0.0921	0.5403	0.3414	0.062*
C6	0.1301 (3)	0.5651 (2)	0.33911 (13)	0.0416 (5)
C7	0.2709 (3)	0.39924 (19)	0.34851 (13)	0.0405 (5)
C8	0.3658 (3)	0.4400 (2)	0.27737 (14)	0.0477 (6)
H8A	0.4248	0.3775	0.2554	0.057*
H8B	0.3046	0.4710	0.2335	0.057*
C9	0.4635 (3)	0.5312 (2)	0.31346 (14)	0.0467 (6)
C10	0.4696 (3)	0.7153 (2)	0.38443 (15)	0.0516 (6)
H10A	0.4560	0.7899	0.3592	0.062*
H10B	0.5748	0.6979	0.3839	0.062*
C11	0.4161 (3)	0.7200 (2)	0.47313 (15)	0.0483 (6)
H11A	0.4732	0.7772	0.5027	0.058*
H11B	0.3131	0.7440	0.4737	0.058*
C12	0.3193 (3)	0.5726 (2)	0.56469 (15)	0.0480 (6)
C13	0.5683 (3)	0.5585 (3)	0.53446 (17)	0.0590 (7)
H13A	0.6327	0.6096	0.5652	0.071*
H13B	0.6190	0.5333	0.4849	0.071*
C14	0.5192 (4)	0.4584 (3)	0.58632 (19)	0.0697 (8)
H14A	0.5224	0.3879	0.5546	0.084*
H14B	0.5826	0.4500	0.6343	0.084*
C15	0.3119 (3)	0.29286 (18)	0.39276 (14)	0.0415 (5)
C16	0.2634 (3)	0.2771 (2)	0.47373 (17)	0.0542 (6)
H16	0.2040	0.3321	0.4989	0.065*
C17	0.3038 (4)	0.1793 (3)	0.51664 (19)	0.0674 (8)
H17	0.2710	0.1690	0.5706	0.081*
C18	0.3914 (3)	0.0977 (3)	0.4807 (2)	0.0658 (8)
H18	0.4195	0.0331	0.5104	0.079*
C19	0.4373 (4)	0.1114 (3)	0.4010 (2)	0.0701 (8)
H19	0.4946	0.0551	0.3759	0.084*
C20	0.3988 (3)	0.2088 (2)	0.35785 (18)	0.0604 (7)
H20	0.4323	0.2180	0.3040	0.072*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0423 (11)	0.0491 (11)	0.0402 (10)	−0.0064 (9)	−0.0003 (9)	0.0029 (9)
N2	0.0395 (11)	0.0438 (10)	0.0415 (10)	−0.0009 (9)	−0.0001 (8)	−0.0040 (9)
N3	0.0414 (11)	0.0531 (11)	0.0428 (11)	0.0005 (9)	0.0037 (9)	0.0065 (9)
O1	0.0407 (10)	0.0837 (13)	0.0761 (13)	0.0036 (10)	0.0055 (9)	0.0061 (12)
O2	0.0511 (11)	0.0706 (12)	0.0815 (13)	0.0082 (11)	0.0214 (10)	0.0049 (10)
O3	0.0706 (12)	0.0607 (11)	0.0575 (11)	0.0065 (10)	0.0181 (10)	0.0150 (9)
C1	0.0470 (13)	0.0482 (13)	0.0351 (12)	0.0017 (11)	−0.0029 (11)	−0.0027 (11)
C2	0.0711 (18)	0.0510 (14)	0.0570 (16)	0.0016 (14)	−0.0068 (15)	0.0076 (12)
C3	0.080 (2)	0.0593 (16)	0.0695 (19)	0.0250 (16)	−0.0144 (17)	0.0092 (15)
C4	0.0580 (17)	0.0736 (18)	0.0623 (17)	0.0226 (16)	−0.0112 (15)	−0.0051 (15)
C5	0.0434 (13)	0.0644 (16)	0.0483 (14)	0.0065 (12)	−0.0018 (11)	−0.0093 (13)
C6	0.0447 (12)	0.0465 (13)	0.0335 (11)	0.0032 (10)	−0.0008 (10)	−0.0061 (10)
C7	0.0412 (13)	0.0444 (11)	0.0358 (11)	−0.0024 (10)	−0.0031 (10)	−0.0058 (10)
C8	0.0558 (14)	0.0542 (13)	0.0330 (11)	0.0057 (12)	0.0038 (11)	−0.0049 (11)
C9	0.0436 (14)	0.0599 (14)	0.0367 (12)	0.0005 (12)	0.0069 (11)	0.0080 (11)
C10	0.0551 (14)	0.0547 (13)	0.0451 (13)	−0.0174 (12)	−0.0012 (12)	0.0062 (11)
C11	0.0559 (15)	0.0455 (13)	0.0435 (13)	−0.0049 (11)	0.0009 (12)	0.0003 (10)
C12	0.0544 (15)	0.0460 (13)	0.0434 (13)	0.0008 (12)	0.0077 (11)	−0.0045 (11)
C13	0.0464 (14)	0.0794 (19)	0.0513 (15)	0.0070 (13)	0.0019 (12)	0.0094 (14)
C14	0.0655 (18)	0.0788 (19)	0.0650 (17)	0.0178 (16)	0.0061 (15)	0.0164 (16)
C15	0.0388 (11)	0.0417 (11)	0.0440 (13)	−0.0032 (10)	−0.0055 (10)	−0.0049 (10)
C16	0.0557 (15)	0.0557 (14)	0.0512 (15)	−0.0024 (12)	−0.0012 (13)	0.0025 (13)
C17	0.0756 (19)	0.0734 (18)	0.0532 (16)	−0.0086 (17)	−0.0077 (15)	0.0144 (15)
C18	0.0613 (17)	0.0592 (17)	0.077 (2)	0.0008 (14)	−0.0237 (16)	0.0153 (15)
C19	0.074 (2)	0.0600 (17)	0.077 (2)	0.0218 (15)	−0.0054 (17)	−0.0025 (15)
C20	0.0643 (18)	0.0614 (16)	0.0554 (16)	0.0138 (14)	−0.0014 (14)	−0.0048 (13)

Geometric parameters (Å, º) top

N1—C9	1.367 (3)	C8—C9	1.501 (3)
N1—C1	1.424 (3)	C8—H8A	0.9700
N1—C10	1.463 (3)	C8—H8B	0.9700
N2—C7	1.280 (3)	C10—C11	1.517 (4)
N2—C6	1.403 (3)	C10—H10A	0.9700
N3—C12	1.350 (3)	C10—H10B	0.9700
N3—C11	1.439 (3)	C11—H11A	0.9700
N3—C13	1.439 (3)	C11—H11B	0.9700
O1—C9	1.216 (3)	C13—C14	1.505 (4)
O2—C12	1.197 (3)	C13—H13A	0.9700
O3—C12	1.350 (3)	C13—H13B	0.9700
O3—C14	1.435 (4)	C14—H14A	0.9700
C1—C2	1.387 (3)	C14—H14B	0.9700
C1—C6	1.398 (3)	C15—C20	1.377 (3)
C2—C3	1.377 (4)	C15—C16	1.395 (4)
C2—H2	0.9300	C16—C17	1.385 (4)
C3—C4	1.378 (4)	C16—H16	0.9300
C3—H3	0.9300	C17—C18	1.367 (4)
C4—C5	1.363 (4)	C17—H17	0.9300
C4—H4	0.9300	C18—C19	1.364 (5)
C5—C6	1.399 (3)	C18—H18	0.9300
C5—H5	0.9300	C19—C20	1.379 (4)
C7—C15	1.480 (3)	C19—H19	0.9300
C7—C8	1.512 (3)	C20—H20	0.9300

C9—N1—C1	122.7 (2)	C11—C10—H10B	109.1
C9—N1—C10	118.8 (2)	H10A—C10—H10B	107.9
C1—N1—C10	118.3 (2)	N3—C11—C10	113.2 (2)
C7—N2—C6	119.6 (2)	N3—C11—H11A	108.9
C12—N3—C11	121.5 (2)	C10—C11—H11A	108.9
C12—N3—C13	111.40 (19)	N3—C11—H11B	108.9
C11—N3—C13	123.5 (2)	C10—C11—H11B	108.9
C12—O3—C14	109.1 (2)	H11A—C11—H11B	107.7
C2—C1—C6	119.6 (2)	O2—C12—O3	122.2 (2)
C2—C1—N1	118.7 (2)	O2—C12—N3	128.1 (2)
C6—C1—N1	121.7 (2)	O3—C12—N3	109.8 (2)
C3—C2—C1	121.2 (3)	N3—C13—C14	101.5 (2)
C3—C2—H2	119.4	N3—C13—H13A	111.5
C1—C2—H2	119.4	C14—C13—H13A	111.5
C2—C3—C4	119.1 (3)	N3—C13—H13B	111.5
C2—C3—H3	120.4	C14—C13—H13B	111.5
C4—C3—H3	120.4	H13A—C13—H13B	109.3
C5—C4—C3	120.7 (3)	O3—C14—C13	105.4 (2)
C5—C4—H4	119.7	O3—C14—H14A	110.7
C3—C4—H4	119.7	C13—C14—H14A	110.7
C4—C5—C6	121.1 (3)	O3—C14—H14B	110.7
C4—C5—H5	119.4	C13—C14—H14B	110.7
C6—C5—H5	119.4	H14A—C14—H14B	108.8
C1—C6—C5	118.3 (2)	C20—C15—C16	118.1 (2)
C1—C6—N2	124.5 (2)	C20—C15—C7	122.7 (2)
C5—C6—N2	117.2 (2)	C16—C15—C7	119.2 (2)
N2—C7—C15	118.8 (2)	C17—C16—C15	119.9 (3)
N2—C7—C8	121.6 (2)	C17—C16—H16	120.0
C15—C7—C8	119.5 (2)	C15—C16—H16	120.0
C9—C8—C7	104.95 (17)	C18—C17—C16	120.7 (3)
C9—C8—H8A	110.8	C18—C17—H17	119.6
C7—C8—H8A	110.8	C16—C17—H17	119.6
C9—C8—H8B	110.8	C19—C18—C17	119.8 (3)
C7—C8—H8B	110.8	C19—C18—H18	120.1
H8A—C8—H8B	108.8	C17—C18—H18	120.1
O1—C9—N1	123.2 (2)	C18—C19—C20	120.0 (3)
O1—C9—C8	122.3 (2)	C18—C19—H19	120.0
N1—C9—C8	114.4 (2)	C20—C19—H19	120.0
N1—C10—C11	112.4 (2)	C15—C20—C19	121.4 (3)
N1—C10—H10A	109.1	C15—C20—H20	119.3
C11—C10—H10A	109.1	C19—C20—H20	119.3
N1—C10—H10B	109.1

C9—N1—C1—C2	−132.7 (2)	C9—N1—C10—C11	−108.0 (2)
C10—N1—C1—C2	52.3 (3)	C1—N1—C10—C11	67.3 (3)
C9—N1—C1—C6	49.8 (3)	C12—N3—C11—C10	−137.1 (2)
C10—N1—C1—C6	−125.2 (2)	C13—N3—C11—C10	66.2 (3)
C6—C1—C2—C3	0.7 (4)	N1—C10—C11—N3	57.5 (3)
N1—C1—C2—C3	−176.8 (3)	C14—O3—C12—O2	176.3 (3)
C1—C2—C3—C4	0.7 (5)	C14—O3—C12—N3	−4.3 (3)
C2—C3—C4—C5	−0.6 (4)	C11—N3—C12—O2	12.8 (4)
C3—C4—C5—C6	−1.0 (4)	C13—N3—C12—O2	172.0 (3)
C2—C1—C6—C5	−2.2 (3)	C11—N3—C12—O3	−166.5 (2)
N1—C1—C6—C5	175.2 (2)	C13—N3—C12—O3	−7.3 (3)
C2—C1—C6—N2	−179.1 (2)	C12—N3—C13—C14	14.8 (3)
N1—C1—C6—N2	−1.6 (3)	C11—N3—C13—C14	173.5 (2)
C4—C5—C6—C1	2.4 (4)	C12—O3—C14—C13	13.4 (3)
C4—C5—C6—N2	179.5 (2)	N3—C13—C14—O3	−16.4 (3)
C7—N2—C6—C1	−42.9 (3)	N2—C7—C15—C20	161.8 (2)
C7—N2—C6—C5	140.2 (2)	C8—C7—C15—C20	−22.5 (3)
C6—N2—C7—C15	173.44 (19)	N2—C7—C15—C16	−19.4 (3)
C6—N2—C7—C8	−2.2 (3)	C8—C7—C15—C16	156.3 (2)
N2—C7—C8—C9	76.5 (3)	C20—C15—C16—C17	0.4 (4)
C15—C7—C8—C9	−99.1 (2)	C7—C15—C16—C17	−178.4 (2)
C1—N1—C9—O1	178.2 (2)	C15—C16—C17—C18	0.2 (4)
C10—N1—C9—O1	−6.8 (3)	C16—C17—C18—C19	−1.3 (4)
C1—N1—C9—C8	−5.5 (3)	C17—C18—C19—C20	1.8 (5)
C10—N1—C9—C8	169.45 (19)	C16—C15—C20—C19	0.1 (4)
C7—C8—C9—O1	107.4 (3)	C7—C15—C20—C19	178.9 (3)
C7—C8—C9—N1	−68.8 (2)	C18—C19—C20—C15	−1.2 (5)

Experimental details

Crystal data
Chemical formula	C₂₀H₁₉N₃O₃
M_r	349.38
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	293
a, b, c (Å)	9.0163 (5), 11.6671 (6), 16.2019 (8)
V (Å³)	1704.34 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.25 × 0.25 × 0.15

Data collection
Diffractometer	Bruker X8 APEXII
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9253, 2053, 1578
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.631

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.102, 0.90
No. of reflections	2053
No. of parameters	235
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.12, −0.16

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

Acknowledgements

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

References

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