2,6-Bis[1-(2-methyl­phenyl­imino)eth­yl]pyridine

Fan, R.-Q.; Ding, X.-D.; Zhou, G.-P.; Yang, Y.-L.

doi:10.1107/S1600536809020522

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1480

doi:10.1107/S1600536809020522

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2,6-Bis[1-(2-methylphenylimino)ethyl]pyridine

Rui-Qing Fan,^a ^* Xiao-Dong Ding,^a Guang-Peng Zhou ^a and Yu-Lin Yang ^a

^aDepartment of Chemistry, Harbin Institute of Technology, Harbin 150001, People's Republic of China
^*Correspondence e-mail: fanruiqing@163.com

(Received 26 May 2009; accepted 29 May 2009; online 6 June 2009)

The molecule of the title compound, C₂₃H₂₃N₃, which was synthesized by the condensation reaction between 2,6-diacetylpyridine and 2-dimethylaniline, adopts an E configuration about both C=N imine bonds. The dihedral angles formed by the benzene rings with the pyridine ring are 89.68 (5) and 53.62 (6)°.

Related literature

For the applications of pyridine-based ligands in sensor technologies and electro-luminescent devices, see: Tang & Vanslyke (1987 ); Wang (2001 ). For the crystal structures of related compounds, see: Mentes et al. (2001 ); Huang et al. (2006 ). For the synthesis, see: Fan et al. (2004 ).

Experimental

Crystal data

C₂₃H₂₃N₃
M_r = 341.44
Monoclinic, P 2₁ /n
a = 12.966 (3) Å
b = 11.304 (2) Å
c = 14.767 (3) Å
β = 115.62 (3)°
V = 1951.6 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 193 K
0.56 × 0.41 × 0.36 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.960, T_max = 0.972
18526 measured reflections
4435 independent reflections
2804 reflections with I > 2σ(I)
R_int = 0.037

Refinement

R[F² > 2σ(F²)] = 0.051
wR(F²) = 0.157
S = 1.06
4435 reflections
235 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablock I. DOI: 10.1107/S1600536809020522/rz2329sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809020522/rz2329Isup2.hkl

checkCIF report

Comment top

Luminescent coordination compounds based on pyridine-type ligands have attracted intensive attention due to their potential application in areas of sensor technologies and electro-luminescent devices (Tang & Vanslyke, 1987; Wang, 2001). In order to explore potential luminescent complexes of this type, we prepared a series of bis(iminoalkyl)pyridine ligands by the condensation reaction of 2,6-diacetylpyridine with the corresponding aniline in methanol (Fan et al., 2004). It is still challenging to design and rationally synthesize ligands with unique structures and functions. In this regard, we report herein the synthesis and crystal structure of the title compound.

The molecule of the title compound (Fig. 1) possesses an approximate C_s symmetry about a plane bisecting the pyridine ring. The pyridine ring is coplanar with the two imino groups, which show typical C═N double bond character (1.2606 (18) and 1.2674 (19) Å for N1═C1 and N3═C7, respectively). These values are in good agreement with those observed in 2,6-bis[1-(phenylimino)ethyl]pyridine (1.266 (4) Å; Mentes et al., 2001) and in 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine (1.265 (2) and 1.271 (2) Å; Huang et al., 2006). The dihedral angles between the C10–C15 and C17–C22 benzene rings and the pyridine ring are 89.68 (5) and 53.62 (6)°, respectively. The crystal packing (Fig. 2) is stabilized only by van der Waals interactions.

Related literature top

For the applications of pyridine-based ligands in sensor technologies and electro-luminescent devices, see: Tang & Vanslyke (1987); Wang (2001). For the crystal structures of related compounds, see: Mentes et al. (2001); Huang et al. (2006).For the synthesis, see: Fan et al. (2004).

Experimental top

The title compound was synthesized according to the literatute method (Fan et al., 2004). To a solution of 2,6-diacetylpyridine (1.1 g, 6.7 mmol) in absolute methanol (25 ml) was added 2-dimethylaniline (2.2 ml, 20.5 mmol). After the addition of several drops of formic acid, the reaction mixture was refluxed for 24 h and then allowed to cool down to room temperature. The crude product precipitated as yellow powder. Yellow block crystals suitable for X-ray diffraction analysis were obtained by slow evaporation of a methanol solution in 85% yield (1.96 g).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structire of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Packing diagram of the title compound viewed along the c axis.

2,6-bis[1-(2-methylphenylimino)ethyl]pyridine top

Crystal data top

C₂₃H₂₃N₃	F(000) = 728
M_r = 341.44	D_x = 1.162 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 18526 reflections
a = 12.966 (3) Å	θ = 3.1–27.5°
b = 11.304 (2) Å	µ = 0.07 mm⁻¹
c = 14.767 (3) Å	T = 193 K
β = 115.62 (3)°	Block, yellow
V = 1951.6 (8) Å³	0.56 × 0.41 × 0.36 mm
Z = 4

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	4435 independent reflections
Radiation source: fine-focus sealed tube	2804 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
phi and ω scans	θ_max = 27.5°, θ_min = 3.1°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −16→16
T_min = 0.960, T_max = 0.972	k = −14→13
18526 measured reflections	l = −19→19

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)] = 0.051	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.157	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0848P)² + 0.041P] where P = (F_o² + 2F_c²)/3
4435 reflections	(Δ/σ)_max < 0.001
235 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.16 e Å⁻³

Crystal data top

C₂₃H₂₃N₃	V = 1951.6 (8) Å³
M_r = 341.44	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 12.966 (3) Å	µ = 0.07 mm⁻¹
b = 11.304 (2) Å	T = 193 K
c = 14.767 (3) Å	0.56 × 0.41 × 0.36 mm
β = 115.62 (3)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	4435 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	2804 reflections with I > 2σ(I)
T_min = 0.960, T_max = 0.972	R_int = 0.037
18526 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.051	0 restraints
wR(F²) = 0.157	H-atom parameters constrained
S = 1.06	Δρ_max = 0.22 e Å⁻³
4435 reflections	Δρ_min = −0.16 e Å⁻³
235 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
N2	0.27847 (10)	0.74889 (10)	0.16139 (9)	0.0458 (3)
N1	−0.01920 (11)	0.79913 (11)	0.03667 (10)	0.0527 (3)
C6	0.37804 (12)	0.80381 (12)	0.18433 (11)	0.0448 (4)
N3	0.57761 (11)	0.77842 (11)	0.25205 (11)	0.0565 (4)
C2	0.18145 (13)	0.80916 (12)	0.10943 (11)	0.0457 (4)
C1	0.07290 (13)	0.74430 (12)	0.08606 (11)	0.0476 (4)
C7	0.48407 (13)	0.73369 (12)	0.24317 (11)	0.0466 (4)
C3	0.18154 (13)	0.92576 (13)	0.08007 (12)	0.0524 (4)
H3B	0.1130	0.9656	0.0444	0.063*
C5	0.38449 (14)	0.92051 (13)	0.15758 (13)	0.0543 (4)
H5A	0.4550	0.9567	0.1751	0.065*
C10	−0.12858 (13)	0.74706 (12)	0.00704 (12)	0.0489 (4)
C17	0.68397 (13)	0.72253 (14)	0.30780 (13)	0.0523 (4)
C15	−0.18677 (13)	0.75912 (12)	0.06699 (12)	0.0522 (4)
C4	0.28403 (14)	0.98142 (13)	0.10444 (13)	0.0586 (4)
H4A	0.2858	1.0595	0.0853	0.070*
C14	−0.29933 (15)	0.72146 (15)	0.02802 (15)	0.0620 (5)
H14A	−0.3395	0.7298	0.0668	0.074*
C22	0.71360 (14)	0.61751 (15)	0.27656 (14)	0.0633 (5)
H22A	0.6602	0.5788	0.2202	0.076*
C9	0.47073 (15)	0.62046 (14)	0.28932 (15)	0.0633 (5)
H9A	0.5443	0.5840	0.3248	0.095*
H9B	0.4213	0.5681	0.2375	0.095*
H9C	0.4381	0.6366	0.3353	0.095*
C18	0.76376 (15)	0.78082 (15)	0.39198 (13)	0.0579 (4)
C8	0.08130 (16)	0.61968 (15)	0.12366 (17)	0.0764 (6)
H8A	0.0058	0.5882	0.1037	0.115*
H8B	0.1217	0.6191	0.1956	0.115*
H8C	0.1217	0.5721	0.0958	0.115*
C13	−0.35352 (16)	0.67238 (16)	−0.06562 (16)	0.0697 (5)
H13A	−0.4295	0.6487	−0.0902	0.084*
C11	−0.18236 (16)	0.69527 (15)	−0.08650 (14)	0.0634 (5)
H11A	−0.1426	0.6850	−0.1254	0.076*
C20	0.90039 (16)	0.62620 (19)	0.41061 (16)	0.0742 (6)
H20A	0.9733	0.5946	0.4454	0.089*
C12	−0.29465 (17)	0.65852 (17)	−0.12285 (15)	0.0721 (5)
H12A	−0.3304	0.6243	−0.1862	0.087*
C19	0.87169 (16)	0.72988 (18)	0.44214 (14)	0.0708 (5)
H19A	0.9259	0.7674	0.4988	0.085*
C16	−0.12855 (18)	0.81252 (18)	0.17075 (15)	0.0768 (6)
H16A	−0.1809	0.8138	0.2009	0.115*
H16B	−0.1049	0.8918	0.1659	0.115*
H16C	−0.0629	0.7659	0.2114	0.115*
C21	0.82176 (17)	0.56955 (18)	0.32815 (17)	0.0744 (5)
H21A	0.8407	0.4990	0.3066	0.089*
C23	0.7334 (2)	0.89394 (18)	0.42839 (17)	0.0874 (6)
H23A	0.6561	0.9154	0.3847	0.131*
H23B	0.7842	0.9558	0.4283	0.131*
H23C	0.7407	0.8829	0.4953	0.131*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N2	0.0389 (7)	0.0437 (7)	0.0531 (7)	0.0021 (5)	0.0183 (6)	0.0030 (5)
N1	0.0407 (7)	0.0476 (7)	0.0659 (9)	0.0017 (5)	0.0193 (6)	0.0079 (6)
C6	0.0412 (8)	0.0442 (8)	0.0508 (8)	0.0034 (6)	0.0217 (7)	0.0030 (6)
N3	0.0409 (8)	0.0550 (7)	0.0719 (9)	0.0030 (6)	0.0227 (7)	0.0109 (6)
C2	0.0413 (8)	0.0460 (8)	0.0493 (8)	0.0043 (6)	0.0191 (7)	0.0026 (6)
C1	0.0423 (8)	0.0458 (8)	0.0533 (9)	0.0019 (6)	0.0193 (7)	0.0031 (6)
C7	0.0421 (8)	0.0441 (7)	0.0537 (9)	0.0027 (6)	0.0208 (7)	−0.0005 (6)
C3	0.0439 (9)	0.0460 (8)	0.0631 (10)	0.0072 (6)	0.0191 (7)	0.0075 (7)
C5	0.0434 (9)	0.0472 (8)	0.0721 (11)	−0.0002 (6)	0.0247 (8)	0.0068 (7)
C10	0.0394 (8)	0.0399 (7)	0.0619 (9)	0.0040 (6)	0.0166 (7)	0.0108 (6)
C17	0.0384 (8)	0.0541 (9)	0.0654 (10)	0.0012 (7)	0.0234 (8)	0.0113 (7)
C15	0.0446 (9)	0.0435 (8)	0.0658 (10)	0.0024 (6)	0.0212 (8)	0.0074 (7)
C4	0.0521 (10)	0.0421 (8)	0.0790 (11)	0.0036 (7)	0.0260 (8)	0.0122 (7)
C14	0.0454 (9)	0.0622 (10)	0.0774 (12)	0.0018 (8)	0.0256 (9)	0.0112 (9)
C22	0.0455 (9)	0.0639 (10)	0.0785 (12)	0.0029 (8)	0.0248 (9)	0.0004 (8)
C9	0.0487 (10)	0.0548 (9)	0.0876 (13)	0.0091 (7)	0.0305 (9)	0.0182 (8)
C18	0.0542 (10)	0.0614 (9)	0.0583 (10)	−0.0042 (8)	0.0245 (8)	0.0091 (7)
C8	0.0511 (10)	0.0542 (10)	0.1118 (16)	0.0021 (8)	0.0239 (10)	0.0249 (10)
C13	0.0429 (9)	0.0704 (11)	0.0806 (13)	−0.0085 (8)	0.0125 (9)	0.0122 (10)
C11	0.0589 (11)	0.0667 (10)	0.0621 (11)	−0.0051 (8)	0.0238 (9)	0.0013 (8)
C20	0.0415 (10)	0.0890 (14)	0.0863 (14)	0.0123 (9)	0.0222 (10)	0.0223 (11)
C12	0.0647 (12)	0.0717 (11)	0.0630 (11)	−0.0148 (9)	0.0116 (10)	−0.0010 (9)
C19	0.0518 (11)	0.0886 (13)	0.0613 (11)	−0.0094 (9)	0.0143 (9)	0.0121 (9)
C16	0.0730 (13)	0.0819 (13)	0.0805 (14)	−0.0175 (10)	0.0380 (11)	−0.0189 (10)
C21	0.0567 (11)	0.0729 (11)	0.1024 (15)	0.0155 (9)	0.0428 (11)	0.0108 (11)
C23	0.1025 (18)	0.0732 (12)	0.0791 (14)	−0.0003 (12)	0.0323 (13)	−0.0034 (10)

Geometric parameters (Å, º) top

N2—C6	1.3374 (18)	C22—H22A	0.9300
N2—C2	1.3420 (18)	C9—H9A	0.9600
N1—C1	1.2606 (18)	C9—H9B	0.9600
N1—C10	1.4187 (19)	C9—H9C	0.9600
C6—C5	1.390 (2)	C18—C19	1.394 (3)
C6—C7	1.497 (2)	C18—C23	1.504 (3)
N3—C7	1.2674 (19)	C8—H8A	0.9600
N3—C17	1.413 (2)	C8—H8B	0.9600
C2—C3	1.388 (2)	C8—H8C	0.9600
C2—C1	1.489 (2)	C13—C12	1.371 (3)
C1—C8	1.501 (2)	C13—H13A	0.9300
C7—C9	1.495 (2)	C11—C12	1.380 (3)
C3—C4	1.370 (2)	C11—H11A	0.9300
C3—H3B	0.9300	C20—C21	1.363 (3)
C5—C4	1.379 (2)	C20—C19	1.371 (3)
C5—H5A	0.9300	C20—H20A	0.9300
C10—C11	1.380 (2)	C12—H12A	0.9300
C10—C15	1.396 (2)	C19—H19A	0.9300
C17—C22	1.387 (2)	C16—H16A	0.9600
C17—C18	1.392 (2)	C16—H16B	0.9600
C15—C14	1.384 (2)	C16—H16C	0.9600
C15—C16	1.511 (3)	C21—H21A	0.9300
C4—H4A	0.9300	C23—H23A	0.9600
C14—C13	1.369 (3)	C23—H23B	0.9600
C14—H14A	0.9300	C23—H23C	0.9600
C22—C21	1.385 (2)

C6—N2—C2	118.22 (12)	C7—C9—H9C	109.5
C1—N1—C10	123.03 (12)	H9A—C9—H9C	109.5
N2—C6—C5	122.59 (13)	H9B—C9—H9C	109.5
N2—C6—C7	116.43 (12)	C17—C18—C19	117.84 (17)
C5—C6—C7	120.96 (13)	C17—C18—C23	120.89 (17)
C7—N3—C17	122.08 (13)	C19—C18—C23	121.26 (18)
N2—C2—C3	122.25 (14)	C1—C8—H8A	109.5
N2—C2—C1	116.17 (12)	C1—C8—H8B	109.5
C3—C2—C1	121.58 (13)	H8A—C8—H8B	109.5
N1—C1—C2	117.13 (13)	C1—C8—H8C	109.5
N1—C1—C8	125.07 (14)	H8A—C8—H8C	109.5
C2—C1—C8	117.79 (13)	H8B—C8—H8C	109.5
N3—C7—C9	126.06 (14)	C14—C13—C12	119.32 (17)
N3—C7—C6	116.53 (13)	C14—C13—H13A	120.3
C9—C7—C6	117.37 (13)	C12—C13—H13A	120.3
C4—C3—C2	119.07 (14)	C10—C11—C12	120.57 (19)
C4—C3—H3B	120.5	C10—C11—H11A	119.7
C2—C3—H3B	120.5	C12—C11—H11A	119.7
C4—C5—C6	118.51 (14)	C21—C20—C19	119.81 (17)
C4—C5—H5A	120.7	C21—C20—H20A	120.1
C6—C5—H5A	120.7	C19—C20—H20A	120.1
C11—C10—C15	119.90 (15)	C13—C12—C11	120.05 (18)
C11—C10—N1	119.33 (16)	C13—C12—H12A	120.0
C15—C10—N1	120.41 (15)	C11—C12—H12A	120.0
C22—C17—C18	119.76 (15)	C20—C19—C18	122.03 (18)
C22—C17—N3	121.99 (15)	C20—C19—H19A	119.0
C18—C17—N3	118.04 (15)	C18—C19—H19A	119.0
C14—C15—C10	117.91 (16)	C15—C16—H16A	109.5
C14—C15—C16	121.28 (17)	C15—C16—H16B	109.5
C10—C15—C16	120.81 (15)	H16A—C16—H16B	109.5
C3—C4—C5	119.35 (14)	C15—C16—H16C	109.5
C3—C4—H4A	120.3	H16A—C16—H16C	109.5
C5—C4—H4A	120.3	H16B—C16—H16C	109.5
C13—C14—C15	122.21 (18)	C20—C21—C22	119.73 (18)
C13—C14—H14A	118.9	C20—C21—H21A	120.1
C15—C14—H14A	118.9	C22—C21—H21A	120.1
C21—C22—C17	120.83 (17)	C18—C23—H23A	109.5
C21—C22—H22A	119.6	C18—C23—H23B	109.5
C17—C22—H22A	119.6	H23A—C23—H23B	109.5
C7—C9—H9A	109.5	C18—C23—H23C	109.5
C7—C9—H9B	109.5	H23A—C23—H23C	109.5
H9A—C9—H9B	109.5	H23B—C23—H23C	109.5

C2—N2—C6—C5	0.8 (2)	C11—C10—C15—C14	−2.1 (2)
C2—N2—C6—C7	179.43 (13)	N1—C10—C15—C14	170.93 (13)
C6—N2—C2—C3	−0.6 (2)	C11—C10—C15—C16	178.34 (15)
C6—N2—C2—C1	−179.79 (13)	N1—C10—C15—C16	−8.6 (2)
C10—N1—C1—C2	178.32 (14)	C2—C3—C4—C5	−0.1 (3)
C10—N1—C1—C8	−2.3 (3)	C6—C5—C4—C3	0.3 (3)
N2—C2—C1—N1	−179.50 (14)	C10—C15—C14—C13	0.8 (2)
C3—C2—C1—N1	1.3 (2)	C16—C15—C14—C13	−179.72 (16)
N2—C2—C1—C8	1.0 (2)	C18—C17—C22—C21	0.1 (3)
C3—C2—C1—C8	−178.12 (16)	N3—C17—C22—C21	174.74 (16)
C17—N3—C7—C9	1.0 (3)	C22—C17—C18—C19	−0.2 (2)
C17—N3—C7—C6	178.40 (14)	N3—C17—C18—C19	−175.06 (15)
N2—C6—C7—N3	169.72 (14)	C22—C17—C18—C23	−179.14 (17)
C5—C6—C7—N3	−11.6 (2)	N3—C17—C18—C23	6.0 (2)
N2—C6—C7—C9	−12.7 (2)	C15—C14—C13—C12	0.7 (3)
C5—C6—C7—C9	165.96 (16)	C15—C10—C11—C12	2.1 (2)
N2—C2—C3—C4	0.3 (2)	N1—C10—C11—C12	−171.07 (15)
C1—C2—C3—C4	179.40 (15)	C14—C13—C12—C11	−0.8 (3)
N2—C6—C5—C4	−0.6 (2)	C10—C11—C12—C13	−0.5 (3)
C7—C6—C5—C4	−179.19 (15)	C21—C20—C19—C18	−0.4 (3)
C1—N1—C10—C11	−93.60 (19)	C17—C18—C19—C20	0.4 (3)
C1—N1—C10—C15	93.31 (19)	C23—C18—C19—C20	179.31 (19)
C7—N3—C17—C22	68.2 (2)	C19—C20—C21—C22	0.3 (3)
C7—N3—C17—C18	−117.05 (18)	C17—C22—C21—C20	−0.1 (3)

Experimental details

Crystal data
Chemical formula	C₂₃H₂₃N₃
M_r	341.44
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	193
a, b, c (Å)	12.966 (3), 11.304 (2), 14.767 (3)
β (°)	115.62 (3)
V (Å³)	1951.6 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.56 × 0.41 × 0.36

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.960, 0.972
No. of measured, independent and observed [I > 2σ(I)] reflections	18526, 4435, 2804
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.157, 1.06
No. of reflections	4435
No. of parameters	235
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.16

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant Nos. 20771030 and 20671025), the Youthful Foundation of Heilongjiang Province of China (grant No. QC06C029) and the Research Fund for the Doctoral Program of Higher Education (grant No. 20070213005).

References

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