Dicyclo­hexyl­ammonium 2-methoxy­benzoate

Judaš, N.; Portada, T.

doi:10.1107/S1600536808007587

Dicyclohexylammonium 2-methoxybenzoate

The asymmetric unit of the title compound, C₁₂H₂₄N⁺·C₈H₇O₃⁻, contains one dicyclohexylammonium cation and one 2-methoxybenzoate anion. Two cations and two anions are linked together to form a four-ion cluster through a set of N—H

O hydrogen bonds. Weak C—H

O hydrogen bonds connect the clusters into chains that are stacked along the crystallographic c axis.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536808007587/wn2244sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536808007587/wn2244Isup2.hkl Contains datablock I

CCDC reference: 688879

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Key indicators

Single-crystal X-ray study
T = 293 K, P = 0.0 kPa
Mean (C-C) = 0.004 Å
R factor = 0.068
wR factor = 0.175
Data-to-parameter ratio = 16.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size .......       0.62 mm
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        C13
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C9
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C1
PLAT480_ALERT_4_C Long H...A H-Bond Reported H20A   ..  O1      ..       2.66 Ang.

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

Comment top

The title compound was synthesized as a model for the purposes of a workshop on parallel synthesis and combinatorial chemistry. The compound was selected because of its resemblance to dicyclohexylammonium salts of substituted cinnamic acids, that are widely known as gelators of organic fluids (Ballabh et al., 2005; Trivedi et al., 2005, Trivedi et al., 2004).

The molecular structure of the title compound is shown in Fig. 1. The asymmetric unit consist of a dicyclohexylammonium cation and a 2-methoxybenzoate anion. The carboxylate group of the anion is twisted with respect to the parent benzene ring by 65.1 (2)°. All bond lengths fall within normal ranges (Allen et al., 1987).

Two cations and two anions self-assemble into a tetrameric structural unit by two hydrogen bonds; N1—H2···O1 and N1—H1···O2ⁱ (Fig. 2, Table 1.).

Weak C20—H20···O1ⁱⁱ hydrogen bonds (Fig. 3, Table 1) link these tetrameric units into chains that are stacked together in a zipper-like manner, so as to produce narrow channels between them (Fig. 4a). The appearance of the channels is consistent with the relatively low calculated density of the title compound (1.14 g cm^-3).

The zipper-like stacking is achieved by the interdigitation of protruding benzene groups in each chain (Fig. 4 b), thus maximizing the intermolecular contacts.

Related literature top

For the crystal structures of dicyclohexylammonium salts of monocarboxylic acids, see: Ng et al. (1999); Ng, Naumov et al. 2001), Ng & Hook (1999); Subramanian et al. (2000). For the crystal structures of dicyclohexylammonium salts of dicarboxylic acids, see: Ballabh et al. (2005); Trivedi et al. (2005); Ng, Chantrapromma et al. (2001). For related literature, see: Zain & Ng (2007); Trivedi et al. (2004); Ng et al. (1991); Allen et al. (1987).

Experimental top

A solution of dicyclohexylamine (363 mg, 2.00 mmol) in toluene (5 ml) was added with stirring to a solution of 2-methoxybenzoic acid (304 mg, 2.00 mmol) in toluene (5 ml). The resulting solution was allowed to stand in an open beaker for several days until crystals of the title compound formed by slow solvent evaporation. The crystals were suitable for single-crystal X-ray diffraction. The compound was also analyzed by thermal methods (TG and DSC). Thermal analyses were performed on METTLER thermal analysis modules DSC823^e and TGA/SDTA851^e. The calorimetric thermogram exhibited one endothermic signal that was sharp and well defined, corresponding to the melting point of the compound. The onset temperature of the signal is T_f = 416 K with enthalpy of fusion, ΔH_fus = 37,9 kJ mol^-1. Degradation of the sample begins above 524 K.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED (Oxford Diffraction, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); Mercury (Macrae et al., 2006); RasTop (Valadon, 2000–2003); POV-RAY (Persistence of Vision, 2004); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radius.
	Fig. 2. Self-assembly of cations and anions through N1—H2···O1 and N1—H1···O2 hydrogen bonds into tetrameric units.
	Fig. 3. Linkage of the tetrameric units into molecular chains through weak C20—H20···O1 hydrogen bonds. Carbon atoms C20 involved in hydrogen bonding are darkened for clarity.
	Fig. 4. Views of the crystal structure of the title compound depicting: (a) the narrow channels between neighboring chains of tetrameric units; (b) the interpenetration of benzene rings belonging to neighboring chains. Atoms of each chain have been color-coded for clarity.

dicyclohexylamonium 2-methoxybenzoate top

Crystal data top

C₁₂H₂₄N⁺·C₈H₇O₃⁻	F(000) = 728
M_r = 333.46	D_x = 1.141 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 416 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 9.2798 (5) Å	Cell parameters from 742 reflections
b = 17.7978 (9) Å	θ = 6.4–21.2°
c = 12.1513 (7) Å	µ = 0.08 mm⁻¹
β = 104.720 (5)°	T = 293 K
V = 1941.04 (18) Å³	Prismatic, colourless
Z = 4	0.62 × 0.41 × 0.35 mm

Data collection top

Oxford Diffraction Xcalibur CCD diffractometer	2750 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.042
Graphite monochromator	θ_max = 26.0°, θ_min = 4.1°
ω scans	h = −11→11
19673 measured reflections	k = −21→21
3789 independent reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.068	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.175	w = 1/[σ²(F_o²) + (0.0745P)² + 0.785P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
3789 reflections	Δρ_max = 0.37 e Å⁻³
225 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.034 (4)

Crystal data top

C₁₂H₂₄N⁺·C₈H₇O₃⁻	V = 1941.04 (18) Å³
M_r = 333.46	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 9.2798 (5) Å	µ = 0.08 mm⁻¹
b = 17.7978 (9) Å	T = 293 K
c = 12.1513 (7) Å	0.62 × 0.41 × 0.35 mm
β = 104.720 (5)°

Data collection top

Oxford Diffraction Xcalibur CCD diffractometer	2750 reflections with I > 2σ(I)
19673 measured reflections	R_int = 0.042
3789 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.068	0 restraints
wR(F²) = 0.175	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.37 e Å⁻³
3789 reflections	Δρ_min = −0.17 e Å⁻³
225 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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
O1	0.2706 (2)	0.08567 (10)	1.00183 (17)	0.0842 (6)
O2	0.04537 (19)	0.13445 (12)	0.96352 (17)	0.0852 (6)
O3	0.0699 (2)	0.14787 (12)	0.72365 (14)	0.0819 (6)
N1	0.2059 (2)	−0.06289 (11)	1.02163 (16)	0.0491 (5)
H1	0.114 (3)	−0.0780 (13)	1.0175 (19)	0.059*
H2	0.209 (2)	−0.0112 (15)	1.0178 (19)	0.059*
C1	0.1749 (2)	0.13270 (11)	0.95593 (17)	0.0471 (5)
C2	0.2251 (2)	0.19520 (11)	0.89133 (17)	0.0438 (5)
C3	0.3308 (3)	0.24641 (13)	0.9464 (2)	0.0634 (6)
H3	0.3731	0.2413	1.0241	0.076*
C4	0.3748 (4)	0.30529 (15)	0.8877 (3)	0.0898 (10)
H4	0.4465	0.3392	0.9258	0.108*
C5	0.3122 (4)	0.31337 (16)	0.7736 (3)	0.0894 (10)
H5	0.3400	0.3535	0.7345	0.107*
C6	0.2088 (3)	0.26265 (16)	0.7164 (2)	0.0750 (8)
H6	0.1671	0.2682	0.6388	0.090*
C7	0.1666 (2)	0.20300 (13)	0.77480 (19)	0.0537 (6)
C8	0.0317 (4)	0.1435 (2)	0.6036 (2)	0.0992 (11)
H8B	−0.0221	0.1878	0.5722	0.149*
H8C	−0.0295	0.1000	0.5795	0.149*
H8A	0.1208	0.1395	0.5776	0.149*
C9	0.2458 (2)	−0.09394 (12)	0.91808 (18)	0.0507 (5)
H9	0.3437	−0.0742	0.9162	0.061*
C10	0.1326 (3)	−0.06616 (16)	0.8135 (2)	0.0761 (7)
H10A	0.1324	−0.0117	0.8129	0.091*
H10B	0.0340	−0.0830	0.8159	0.091*
C11	0.1681 (4)	−0.09527 (19)	0.7053 (2)	0.0940 (10)
H11B	0.0913	−0.0787	0.6397	0.113*
H11A	0.2622	−0.0742	0.6992	0.113*
C12	0.1775 (4)	−0.17925 (19)	0.7044 (3)	0.0950 (10)
H12B	0.2082	−0.1956	0.6377	0.114*
H12A	0.0800	−0.2005	0.7005	0.114*
C13	0.2877 (5)	−0.2071 (2)	0.8103 (3)	0.1075 (11)
H13A	0.3869	−0.1911	0.8086	0.129*
H13B	0.2865	−0.2616	0.8106	0.129*
C14	0.2540 (3)	−0.17841 (14)	0.9200 (2)	0.0760 (8)
H14B	0.1600	−0.1991	0.9271	0.091*
H14A	0.3316	−0.1948	0.9852	0.091*
C15	0.3019 (2)	−0.08294 (11)	1.13645 (17)	0.0471 (5)
H15	0.2968	−0.1374	1.1467	0.057*
C16	0.2390 (2)	−0.04421 (14)	1.2256 (2)	0.0599 (6)
H16A	0.2334	0.0094	1.2110	0.072*
H16B	0.1386	−0.0623	1.2194	0.072*
C17	0.3332 (3)	−0.05828 (17)	1.3448 (2)	0.0743 (7)
H17B	0.3262	−0.1109	1.3637	0.089*
H17A	0.2947	−0.0287	1.3981	0.089*
C18	0.4956 (3)	−0.03803 (17)	1.3571 (2)	0.0755 (7)
H18A	0.5047	0.0159	1.3490	0.091*
H18B	0.5541	−0.0522	1.4323	0.091*
C19	0.5553 (3)	−0.07794 (15)	1.2679 (2)	0.0717 (7)
H19B	0.6573	−0.0623	1.2748	0.086*
H19A	0.5555	−0.1317	1.2812	0.086*
C20	0.4629 (2)	−0.06121 (14)	1.1488 (2)	0.0594 (6)
H20A	0.5021	−0.0890	1.0941	0.071*
H20B	0.4689	−0.0080	1.1329	0.071*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.1052 (14)	0.0553 (11)	0.1037 (15)	0.0129 (10)	0.0479 (12)	0.0276 (10)
O2	0.0615 (10)	0.1125 (16)	0.0879 (14)	−0.0220 (10)	0.0307 (9)	0.0165 (11)
O3	0.0777 (11)	0.1234 (17)	0.0406 (9)	−0.0256 (11)	0.0079 (8)	−0.0009 (9)
N1	0.0455 (9)	0.0437 (10)	0.0621 (12)	0.0020 (8)	0.0210 (8)	0.0081 (8)
C1	0.0600 (12)	0.0460 (12)	0.0374 (11)	−0.0104 (10)	0.0166 (9)	−0.0060 (9)
C2	0.0455 (10)	0.0423 (11)	0.0465 (12)	0.0037 (8)	0.0168 (9)	0.0004 (8)
C3	0.0789 (16)	0.0585 (14)	0.0571 (14)	−0.0167 (12)	0.0252 (12)	−0.0057 (11)
C4	0.121 (2)	0.0557 (16)	0.108 (3)	−0.0344 (16)	0.056 (2)	−0.0122 (15)
C5	0.127 (3)	0.0545 (16)	0.108 (3)	0.0052 (17)	0.068 (2)	0.0244 (16)
C6	0.0877 (18)	0.0762 (18)	0.0692 (17)	0.0236 (15)	0.0344 (14)	0.0327 (14)
C7	0.0502 (11)	0.0625 (14)	0.0503 (13)	0.0092 (10)	0.0164 (10)	0.0082 (10)
C8	0.091 (2)	0.152 (3)	0.0475 (16)	0.004 (2)	0.0051 (14)	−0.0046 (18)
C9	0.0505 (11)	0.0522 (12)	0.0529 (13)	−0.0041 (9)	0.0196 (10)	0.0033 (9)
C10	0.0922 (19)	0.0692 (17)	0.0626 (17)	0.0069 (14)	0.0116 (14)	0.0055 (13)
C11	0.125 (3)	0.091 (2)	0.0612 (18)	−0.0079 (19)	0.0165 (17)	0.0017 (15)
C12	0.121 (3)	0.093 (2)	0.071 (2)	−0.0183 (19)	0.0259 (18)	−0.0164 (17)
C13	0.164 (3)	0.078 (2)	0.088 (2)	0.027 (2)	0.046 (2)	−0.0125 (17)
C14	0.107 (2)	0.0544 (15)	0.0715 (18)	0.0130 (14)	0.0313 (15)	0.0015 (12)
C15	0.0506 (11)	0.0382 (10)	0.0542 (13)	0.0017 (8)	0.0165 (10)	0.0060 (9)
C16	0.0547 (12)	0.0597 (14)	0.0712 (16)	−0.0047 (10)	0.0268 (11)	−0.0068 (11)
C17	0.0851 (18)	0.0795 (18)	0.0591 (16)	−0.0140 (14)	0.0200 (13)	−0.0135 (13)
C18	0.0735 (16)	0.0733 (17)	0.0737 (18)	−0.0050 (13)	0.0074 (13)	−0.0142 (14)
C19	0.0571 (13)	0.0656 (16)	0.0864 (19)	0.0069 (12)	0.0071 (13)	−0.0050 (14)
C20	0.0476 (11)	0.0629 (14)	0.0698 (16)	0.0050 (10)	0.0189 (11)	0.0007 (11)

Geometric parameters (Å, º) top

O1—C1	1.244 (3)	C11—C12	1.498 (5)
O2—C1	1.229 (3)	C11—H11B	0.9700
O3—C7	1.368 (3)	C11—H11A	0.9700
O3—C8	1.413 (3)	C12—C13	1.510 (5)
N1—C15	1.495 (3)	C12—H12B	0.9700
N1—C9	1.504 (3)	C12—H12A	0.9700
N1—H1	0.88 (2)	C13—C14	1.532 (4)
N1—H2	0.92 (3)	C13—H13A	0.9700
C1—C2	1.502 (3)	C13—H13B	0.9700
C2—C3	1.381 (3)	C14—H14B	0.9700
C2—C7	1.389 (3)	C14—H14A	0.9700
C3—C4	1.386 (4)	C15—C20	1.513 (3)
C3—H3	0.9300	C15—C16	1.520 (3)
C4—C5	1.368 (4)	C15—H15	0.9800
C4—H4	0.9300	C16—C17	1.511 (3)
C5—C6	1.371 (4)	C16—H16A	0.9700
C5—H5	0.9300	C16—H16B	0.9700
C6—C7	1.387 (3)	C17—C18	1.520 (4)
C6—H6	0.9300	C17—H17B	0.9700
C8—H8B	0.9600	C17—H17A	0.9700
C8—H8C	0.9600	C18—C19	1.513 (4)
C8—H8A	0.9600	C18—H18A	0.9700
C9—C14	1.505 (3)	C18—H18B	0.9700
C9—C10	1.511 (3)	C19—C20	1.513 (3)
C9—H9	0.9800	C19—H19B	0.9700
C10—C11	1.526 (4)	C19—H19A	0.9700
C10—H10A	0.9700	C20—H20A	0.9700
C10—H10B	0.9700	C20—H20B	0.9700

C7—O3—C8	118.2 (2)	C11—C12—H12B	109.5
C15—N1—C9	118.55 (16)	C13—C12—H12B	109.5
C15—N1—H1	108.5 (15)	C11—C12—H12A	109.5
C9—N1—H1	106.2 (15)	C13—C12—H12A	109.5
C15—N1—H2	105.4 (14)	H12B—C12—H12A	108.1
C9—N1—H2	107.8 (14)	C12—C13—C14	112.8 (3)
H1—N1—H2	110 (2)	C12—C13—H13A	109.0
O2—C1—O1	125.7 (2)	C14—C13—H13A	109.0
O2—C1—C2	117.3 (2)	C12—C13—H13B	109.0
O1—C1—C2	116.86 (18)	C14—C13—H13B	109.0
C3—C2—C7	118.3 (2)	H13A—C13—H13B	107.8
C3—C2—C1	120.77 (19)	C9—C14—C13	109.9 (2)
C7—C2—C1	120.94 (18)	C9—C14—H14B	109.7
C2—C3—C4	121.0 (3)	C13—C14—H14B	109.7
C2—C3—H3	119.5	C9—C14—H14A	109.7
C4—C3—H3	119.5	C13—C14—H14A	109.7
C5—C4—C3	119.8 (3)	H14B—C14—H14A	108.2
C5—C4—H4	120.1	N1—C15—C20	111.74 (17)
C3—C4—H4	120.1	N1—C15—C16	108.11 (17)
C4—C5—C6	120.4 (2)	C20—C15—C16	111.23 (18)
C4—C5—H5	119.8	N1—C15—H15	108.6
C6—C5—H5	119.8	C20—C15—H15	108.6
C5—C6—C7	119.8 (3)	C16—C15—H15	108.6
C5—C6—H6	120.1	C17—C16—C15	112.00 (19)
C7—C6—H6	120.1	C17—C16—H16A	109.2
O3—C7—C6	123.7 (2)	C15—C16—H16A	109.2
O3—C7—C2	115.66 (19)	C17—C16—H16B	109.2
C6—C7—C2	120.6 (2)	C15—C16—H16B	109.2
O3—C8—H8B	109.5	H16A—C16—H16B	107.9
O3—C8—H8C	109.5	C16—C17—C18	111.9 (2)
H8B—C8—H8C	109.5	C16—C17—H17B	109.2
O3—C8—H8A	109.5	C18—C17—H17B	109.2
H8B—C8—H8A	109.5	C16—C17—H17A	109.2
H8C—C8—H8A	109.5	C18—C17—H17A	109.2
N1—C9—C14	112.10 (18)	H17B—C17—H17A	107.9
N1—C9—C10	108.46 (18)	C19—C18—C17	110.6 (2)
C14—C9—C10	111.2 (2)	C19—C18—H18A	109.5
N1—C9—H9	108.3	C17—C18—H18A	109.5
C14—C9—H9	108.3	C19—C18—H18B	109.5
C10—C9—H9	108.3	C17—C18—H18B	109.5
C9—C10—C11	110.9 (2)	H18A—C18—H18B	108.1
C9—C10—H10A	109.5	C20—C19—C18	111.8 (2)
C11—C10—H10A	109.5	C20—C19—H19B	109.3
C9—C10—H10B	109.5	C18—C19—H19B	109.3
C11—C10—H10B	109.5	C20—C19—H19A	109.3
H10A—C10—H10B	108.0	C18—C19—H19A	109.3
C12—C11—C10	111.7 (3)	H19B—C19—H19A	107.9
C12—C11—H11B	109.3	C19—C20—C15	110.46 (19)
C10—C11—H11B	109.3	C19—C20—H20A	109.6
C12—C11—H11A	109.3	C15—C20—H20A	109.6
C10—C11—H11A	109.3	C19—C20—H20B	109.6
H11B—C11—H11A	107.9	C15—C20—H20B	109.6
C11—C12—C13	110.5 (3)	H20A—C20—H20B	108.1

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H2···O1	0.92 (3)	1.84 (3)	2.735 (3)	163 (2)
N1—H1···O2ⁱ	0.88 (2)	1.85 (3)	2.703 (2)	162 (2)
C20—H20A···O1ⁱⁱ	0.97	2.66	3.457 (3)	140

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

Experimental details

Crystal data
Chemical formula	C₁₂H₂₄N⁺·C₈H₇O₃⁻
M_r	333.46
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	9.2798 (5), 17.7978 (9), 12.1513 (7)
β (°)	104.720 (5)
V (Å³)	1941.04 (18)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.62 × 0.41 × 0.35

Data collection
Diffractometer	Oxford Diffraction Xcalibur CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	19673, 3789, 2750
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.068, 0.175, 1.03
No. of reflections	3789
No. of parameters	225
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.17

Computer programs: CrysAlis CCD (Oxford Diffraction, 2003), CrysAlis RED (Oxford Diffraction, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997); Mercury (Macrae et al., 2006); RasTop (Valadon, 2000–2003); POV-RAY (Persistence of Vision, 2004), WinGX (Farrugia, 1999).