4-[5-(Pyridin-4-yl)-1,3,4-oxadiazol-2-yl]pyridinium benzoate

Han, M.T.; Zhang, Y.

doi:10.1107/S1600536811001358

organic compounds

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Volume 67| Part 2| February 2011| Page o447

doi:10.1107/S1600536811001358

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4-[5-(Pyridin-4-yl)-1,3,4-oxadiazol-2-yl]pyridinium benzoate

Meng Ting Han ^a and Yuan Zhang ^a ^*

^aOrdered Matter Science Research Center, College of Chemistry and Chemical, Engineering, Southeast UniVersity, Nanjing 211189, People's Republic of China
^*Correspondence e-mail: zhangshelley86@hotmail.com

(Received 11 December 2010; accepted 10 January 2011; online 22 January 2011)

In the title compound, C₁₂H₉N₄O⁺·C₇H₅O₂⁻, π–π stacking interactions [centroid–centroid distance = 3.6275 (14) Å] stabilize the crystal structure. The dihedral angles between the central ring and the terminal rings are 3.27 (12) and 10.30 (13)°.

Related literature

For background to the development of ferroelectric compounds, see: Haertling et al. (1999 ); Homes et al. (2001 ). For the synthesis of a variety of compounds with potential piezoelectric and ferroelectric properties, see: Ye et al. (2006 ); Zhang et al. (2008 ).

Experimental

Crystal data

C₁₂H₉N₄O⁺·C₇H₅O₂⁻
M_r = 346.34
Monoclinic, P 2₁ /c
a = 20.459 (4) Å
b = 7.1958 (14) Å
c = 11.249 (2) Å
β = 90.53 (3)°
V = 1656.0 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 293 K
0.20 × 0.20 × 0.20 mm

Data collection

Rigaku Mercury2 diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ) T_min = 0.854, T_max = 1.000
16725 measured reflections
3808 independent reflections
2248 reflections with I > 2σ(I)
R_int = 0.064

Refinement

R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.171
S = 1.02
3808 reflections
236 parameters
H-atom parameters constrained
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O2ⁱ	0.86	1.79	2.648 (2)	174
C8—H8⋯O1ⁱⁱ	0.93	2.48	3.371 (3)	161
Symmetry codes: (i) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x, -y+1, -z.

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; 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 datablocks I, global. DOI: 10.1107/S1600536811001358/jh2244sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811001358/jh2244Isup2.hkl

checkCIF report

Comment top

At present, much attention in ferroelectric material field is focused on developing ferroelectric pure organic or inorganic compounds (Haertling et al. 1999; Homes et al. 2001). Recently we have reported the synthesis of a variety of compounds (Ye et al., 2006; Zhang et al., 2008), which have potential piezoelectric and ferroelectric properties. In order to find more dielectric ferroelectric materials, we investigate the physical properties of the title compound(Fig. 1). The dielectric constant of the title compound as a function of temperature indicates that the permittivity is basically temperature-independent (dielectric constant equaling to 3.6 to 4.7), suggesting that this compound should be not a real ferroelectrics or there may be no distinct phase transition occurred within the measured temperature range. Similarly, below the melting point (374 K) of the compound, the dielectric constant as a function of temperature also goes smoothly, and there is no dielectric anomaly observed (dielectric constant equaling to 3.0 to 4.2).Herein, we report the synthesis and crystal structure of the title compound.

The asymmetric unit of (I) consists of one bpo cation and one benzoate anions. The π—π packing interaction of adjacent rings with Cg(1)—Cg(4), 3.6275 (14) A °; Cg(3)—Cg(3), 4.1148 (16) A °; [Cg(1), Cg(3) and Cg(4) are the centroids of rings, where Cg(1): O3/C13/N2/N3/C14; Cg(3): N4/C15–C19; Cg(4): C2–C7;],make great contribution to the stability of the crystal structure.

Related literature top

For background to the development of ferroelectric pure organic or inorganic compounds , see: Haertling et al. (1999); Homes et al. (2001). For the synthesis of a variety of compounds with potential piezoelectric and ferroelectric properties, see: Ye et al. (2006); Zhang et al. (2008).

Experimental top

A mix of 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (2.24 g, 0.01 mol) and benzoate acid (2.44 g,0.02 mol) in methanol (20 ml) was stirred until clear. After several days, the title compound was formed and recrystallized from solution to afford colourlesss prismatic crystals suitable for X-ray analysis.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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. Perspective structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

4-[5-(Pyridin-4-yl)-1,3,4-oxadiazol-2-yl]pyridinium benzoate top

Crystal data top

C₁₂H₉N₄O⁺·C₇H₅O₂⁻	F(000) = 720
M_r = 346.34	D_x = 1.389 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3808 reflections
a = 20.459 (4) Å	θ = 2.6–27.5°
b = 7.1958 (14) Å	µ = 0.10 mm⁻¹
c = 11.249 (2) Å	T = 293 K
β = 90.53 (3)°	Prism, colourless
V = 1656.0 (5) Å³	0.20 × 0.20 × 0.20 mm
Z = 4

Data collection top

Rigaku Mercury2 diffractometer	3808 independent reflections
Radiation source: fine-focus sealed tube	2248 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.064
Detector resolution: 13.6612 pixels mm^-1	θ_max = 27.5°, θ_min = 3.0°
CCD_Profile_fitting scans	h = −26→26
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −9→9
T_min = 0.854, T_max = 1.000	l = −14→14
16725 measured reflections

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)] = 0.059	H-atom parameters constrained
wR(F²) = 0.171	w = 1/[σ²(F_o²) + (0.079P)² + 0.2253P] where P = (F_o² + 2F_c²)/3
S = 1.02	(Δ/σ)_max < 0.001
3808 reflections	Δρ_max = 0.27 e Å⁻³
236 parameters	Δρ_min = −0.28 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0130 (18)

Crystal data top

C₁₂H₉N₄O⁺·C₇H₅O₂⁻	V = 1656.0 (5) Å³
M_r = 346.34	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 20.459 (4) Å	µ = 0.10 mm⁻¹
b = 7.1958 (14) Å	T = 293 K
c = 11.249 (2) Å	0.20 × 0.20 × 0.20 mm
β = 90.53 (3)°

Data collection top

Rigaku Mercury2 diffractometer	3808 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	2248 reflections with I > 2σ(I)
T_min = 0.854, T_max = 1.000	R_int = 0.064
16725 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.059	0 restraints
wR(F²) = 0.171	H-atom parameters constrained
S = 1.02	Δρ_max = 0.27 e Å⁻³
3808 reflections	Δρ_min = −0.28 e Å⁻³
236 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
C1	0.11341 (11)	0.8827 (3)	0.1577 (2)	0.0468 (5)
C2	0.18546 (10)	0.8838 (3)	0.13768 (18)	0.0406 (5)
C3	0.22890 (10)	0.9438 (3)	0.22500 (19)	0.0453 (5)
H3	0.2133	0.9853	0.2977	0.054*
C4	0.29500 (11)	0.9420 (3)	0.2041 (2)	0.0529 (6)
H4	0.3240	0.9831	0.2626	0.064*
C5	0.31834 (12)	0.8796 (3)	0.0974 (2)	0.0602 (7)
H5	0.3631	0.8780	0.0839	0.072*
C6	0.27599 (13)	0.8197 (3)	0.0105 (2)	0.0625 (7)
H6	0.2921	0.7771	−0.0615	0.075*
C7	0.20926 (12)	0.8224 (3)	0.02954 (19)	0.0510 (6)
H7	0.1805	0.7831	−0.0299	0.061*
C8	0.04872 (11)	0.3443 (3)	0.0797 (2)	0.0566 (6)
H8	0.0171	0.3137	0.0231	0.068*
C9	0.11320 (10)	0.3396 (3)	0.0482 (2)	0.0494 (6)
H9	0.1251	0.3092	−0.0290	0.059*
C10	0.16028 (10)	0.3805 (3)	0.13262 (18)	0.0398 (5)
C11	0.14062 (10)	0.4269 (3)	0.2463 (2)	0.0471 (6)
H11	0.1712	0.4538	0.3054	0.057*
C12	0.07469 (11)	0.4324 (3)	0.2698 (2)	0.0545 (6)
H12	0.0612	0.4662	0.3455	0.065*
C13	0.22928 (10)	0.3753 (3)	0.10114 (18)	0.0391 (5)
C14	0.33195 (10)	0.3951 (3)	0.12671 (18)	0.0401 (5)
C15	0.50844 (12)	0.4366 (4)	0.2044 (3)	0.0739 (8)
H15	0.5481	0.4410	0.1649	0.089*
C16	0.45215 (11)	0.4228 (4)	0.1364 (2)	0.0634 (7)
H16	0.4541	0.4184	0.0539	0.076*
C17	0.39284 (10)	0.4158 (3)	0.19378 (19)	0.0430 (5)
C18	0.39322 (11)	0.4232 (3)	0.3154 (2)	0.0572 (7)
H18	0.3542	0.4195	0.3572	0.069*
C19	0.45201 (13)	0.4362 (4)	0.3748 (2)	0.0721 (8)
H19	0.4513	0.4400	0.4575	0.086*
N1	0.02979 (9)	0.3912 (3)	0.1885 (2)	0.0577 (6)
H1A	−0.0111	0.3947	0.2058	0.069*
N2	0.25515 (9)	0.3426 (3)	−0.00105 (16)	0.0489 (5)
N3	0.32318 (9)	0.3568 (3)	0.01599 (16)	0.0493 (5)
N4	0.50991 (10)	0.4439 (3)	0.3221 (2)	0.0726 (7)
O1	0.07395 (8)	0.8483 (3)	0.08005 (16)	0.0711 (5)
O2	0.09672 (7)	0.9211 (2)	0.26772 (15)	0.0629 (5)
O3	0.27482 (6)	0.40949 (19)	0.18688 (12)	0.0406 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0439 (13)	0.0411 (12)	0.0553 (15)	−0.0043 (10)	−0.0113 (11)	−0.0002 (10)
C2	0.0444 (12)	0.0344 (11)	0.0429 (12)	−0.0029 (9)	−0.0044 (9)	0.0034 (9)
C3	0.0413 (12)	0.0522 (13)	0.0422 (12)	−0.0002 (10)	−0.0042 (9)	0.0024 (10)
C4	0.0401 (13)	0.0595 (15)	0.0591 (15)	−0.0068 (11)	−0.0098 (11)	0.0076 (11)
C5	0.0448 (14)	0.0601 (16)	0.0758 (18)	−0.0034 (12)	0.0100 (13)	0.0098 (13)
C6	0.0682 (18)	0.0578 (16)	0.0618 (16)	−0.0058 (13)	0.0178 (13)	−0.0026 (12)
C7	0.0615 (15)	0.0460 (13)	0.0456 (13)	−0.0091 (11)	−0.0039 (11)	0.0015 (10)
C8	0.0395 (13)	0.0617 (15)	0.0682 (17)	−0.0021 (11)	−0.0132 (12)	−0.0008 (12)
C9	0.0428 (13)	0.0561 (14)	0.0492 (13)	0.0003 (10)	−0.0092 (10)	−0.0042 (11)
C10	0.0370 (11)	0.0373 (11)	0.0451 (12)	−0.0022 (9)	−0.0050 (9)	0.0046 (9)
C11	0.0388 (12)	0.0560 (14)	0.0464 (13)	−0.0034 (10)	−0.0063 (10)	0.0027 (10)
C12	0.0451 (13)	0.0617 (16)	0.0569 (15)	0.0032 (11)	0.0027 (11)	0.0064 (11)
C13	0.0407 (11)	0.0394 (12)	0.0372 (11)	−0.0030 (9)	−0.0074 (9)	−0.0002 (9)
C14	0.0353 (11)	0.0432 (12)	0.0419 (12)	−0.0020 (9)	0.0049 (9)	0.0026 (9)
C15	0.0372 (14)	0.103 (2)	0.081 (2)	−0.0078 (14)	0.0073 (13)	−0.0025 (16)
C16	0.0410 (13)	0.092 (2)	0.0574 (15)	−0.0070 (13)	0.0037 (11)	0.0018 (13)
C17	0.0362 (11)	0.0467 (13)	0.0460 (13)	−0.0023 (9)	0.0008 (9)	0.0057 (9)
C18	0.0394 (13)	0.0816 (18)	0.0506 (14)	−0.0053 (12)	−0.0014 (11)	0.0011 (12)
C19	0.0539 (16)	0.104 (2)	0.0579 (16)	−0.0041 (15)	−0.0127 (13)	0.0004 (15)
N1	0.0328 (10)	0.0649 (13)	0.0754 (15)	0.0006 (9)	0.0003 (10)	0.0121 (11)
N2	0.0457 (11)	0.0590 (12)	0.0419 (11)	0.0019 (9)	−0.0016 (8)	−0.0020 (8)
N3	0.0417 (11)	0.0635 (12)	0.0427 (11)	0.0022 (9)	−0.0006 (8)	−0.0010 (9)
N4	0.0459 (13)	0.0927 (17)	0.0788 (17)	−0.0042 (11)	−0.0120 (11)	0.0011 (13)
O1	0.0483 (10)	0.0923 (14)	0.0722 (12)	−0.0078 (9)	−0.0216 (9)	−0.0066 (10)
O2	0.0431 (9)	0.0843 (13)	0.0613 (11)	−0.0048 (8)	0.0007 (8)	−0.0140 (9)
O3	0.0325 (8)	0.0515 (9)	0.0379 (8)	−0.0036 (6)	−0.0017 (6)	0.0002 (6)

Geometric parameters (Å, º) top

C1—O1	1.210 (2)	C11—C12	1.377 (3)
C1—O2	1.316 (3)	C11—H11	0.9300
C1—C2	1.493 (3)	C12—N1	1.323 (3)
C2—C7	1.387 (3)	C12—H12	0.9300
C2—C3	1.387 (3)	C13—N2	1.292 (3)
C3—C4	1.375 (3)	C13—O3	1.357 (2)
C3—H3	0.9300	C14—N3	1.287 (3)
C4—C5	1.372 (3)	C14—O3	1.360 (2)
C4—H4	0.9300	C14—C17	1.458 (3)
C5—C6	1.370 (3)	C15—N4	1.324 (3)
C5—H5	0.9300	C15—C16	1.380 (3)
C6—C7	1.384 (3)	C15—H15	0.9300
C6—H6	0.9300	C16—C17	1.381 (3)
C7—H7	0.9300	C16—H16	0.9300
C8—N1	1.332 (3)	C17—C18	1.369 (3)
C8—C9	1.369 (3)	C18—C19	1.374 (3)
C8—H8	0.9300	C18—H18	0.9300
C9—C10	1.378 (3)	C19—N4	1.331 (3)
C9—H9	0.9300	C19—H19	0.9300
C10—C11	1.385 (3)	N1—H1A	0.8600
C10—C13	1.459 (3)	N2—N3	1.407 (2)

O1—C1—O2	123.0 (2)	C10—C11—H11	120.7
O1—C1—C2	123.0 (2)	N1—C12—C11	122.4 (2)
O2—C1—C2	113.95 (18)	N1—C12—H12	118.8
C7—C2—C3	119.5 (2)	C11—C12—H12	118.8
C7—C2—C1	119.06 (19)	N2—C13—O3	112.41 (18)
C3—C2—C1	121.43 (19)	N2—C13—C10	128.76 (19)
C4—C3—C2	120.0 (2)	O3—C13—C10	118.84 (17)
C4—C3—H3	120.0	N3—C14—O3	112.67 (18)
C2—C3—H3	120.0	N3—C14—C17	129.31 (19)
C5—C4—C3	120.2 (2)	O3—C14—C17	117.96 (18)
C5—C4—H4	119.9	N4—C15—C16	124.6 (2)
C3—C4—H4	119.9	N4—C15—H15	117.7
C6—C5—C4	120.3 (2)	C16—C15—H15	117.7
C6—C5—H5	119.9	C15—C16—C17	118.4 (2)
C4—C5—H5	119.9	C15—C16—H16	120.8
C5—C6—C7	120.2 (2)	C17—C16—H16	120.8
C5—C6—H6	119.9	C18—C17—C16	118.0 (2)
C7—C6—H6	119.9	C18—C17—C14	121.20 (19)
C6—C7—C2	119.7 (2)	C16—C17—C14	120.8 (2)
C6—C7—H7	120.2	C17—C18—C19	119.1 (2)
C2—C7—H7	120.2	C17—C18—H18	120.5
N1—C8—C9	122.2 (2)	C19—C18—H18	120.5
N1—C8—H8	118.9	N4—C19—C18	124.4 (3)
C9—C8—H8	118.9	N4—C19—H19	117.8
C8—C9—C10	119.1 (2)	C18—C19—H19	117.8
C8—C9—H9	120.5	C12—N1—C8	119.1 (2)
C10—C9—H9	120.5	C12—N1—H1A	120.5
C9—C10—C11	118.7 (2)	C8—N1—H1A	120.5
C9—C10—C13	119.94 (19)	C13—N2—N3	106.18 (17)
C11—C10—C13	121.35 (18)	C14—N3—N2	106.04 (17)
C12—C11—C10	118.5 (2)	C15—N4—C19	115.6 (2)
C12—C11—H11	120.7	C13—O3—C14	102.71 (15)

O1—C1—C2—C7	−7.7 (3)	C15—C16—C17—C18	0.1 (4)
O2—C1—C2—C7	171.85 (19)	C15—C16—C17—C14	−178.0 (2)
O1—C1—C2—C3	172.7 (2)	N3—C14—C17—C18	−167.8 (2)
O2—C1—C2—C3	−7.7 (3)	O3—C14—C17—C18	9.0 (3)
C7—C2—C3—C4	0.0 (3)	N3—C14—C17—C16	10.2 (4)
C1—C2—C3—C4	179.54 (19)	O3—C14—C17—C16	−172.9 (2)
C2—C3—C4—C5	−0.5 (3)	C16—C17—C18—C19	−0.3 (4)
C3—C4—C5—C6	0.4 (4)	C14—C17—C18—C19	177.8 (2)
C4—C5—C6—C7	0.3 (4)	C17—C18—C19—N4	0.6 (4)
C5—C6—C7—C2	−0.8 (4)	C11—C12—N1—C8	−0.6 (3)
C3—C2—C7—C6	0.7 (3)	C9—C8—N1—C12	−0.9 (4)
C1—C2—C7—C6	−178.9 (2)	O3—C13—N2—N3	−0.5 (2)
N1—C8—C9—C10	1.5 (4)	C10—C13—N2—N3	179.14 (19)
C8—C9—C10—C11	−0.6 (3)	O3—C14—N3—N2	−0.4 (2)
C8—C9—C10—C13	179.7 (2)	C17—C14—N3—N2	176.6 (2)
C9—C10—C11—C12	−0.8 (3)	C13—N2—N3—C14	0.5 (2)
C13—C10—C11—C12	178.89 (19)	C16—C15—N4—C19	0.3 (4)
C10—C11—C12—N1	1.4 (3)	C18—C19—N4—C15	−0.5 (4)
C9—C10—C13—N2	2.8 (3)	N2—C13—O3—C14	0.2 (2)
C11—C10—C13—N2	−176.8 (2)	C10—C13—O3—C14	−179.42 (17)
C9—C10—C13—O3	−177.63 (18)	N3—C14—O3—C13	0.1 (2)
C11—C10—C13—O3	2.7 (3)	C17—C14—O3—C13	−177.24 (18)
N4—C15—C16—C17	−0.1 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O2ⁱ	0.86	1.79	2.648 (2)	174
C8—H8···O1ⁱⁱ	0.93	2.48	3.371 (3)	161

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

Experimental details

Crystal data
Chemical formula	C₁₂H₉N₄O⁺·C₇H₅O₂⁻
M_r	346.34
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	20.459 (4), 7.1958 (14), 11.249 (2)
β (°)	90.53 (3)
V (Å³)	1656.0 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.20 × 0.20 × 0.20

Data collection
Diffractometer	Rigaku Mercury2 diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2005)
T_min, T_max	0.854, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	16725, 3808, 2248
R_int	0.064
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.059, 0.171, 1.02
No. of reflections	3808
No. of parameters	236
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.28

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O2ⁱ	0.86	1.79	2.648 (2)	174
C8—H8···O1ⁱⁱ	0.93	2.48	3.371 (3)	161

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

Acknowledgements

The authors are grateful to the starter fund of Southeast University for financial support to buy the X-ray diffractometer.

References

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