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ISSN: 2056-9890

1-(2-Carb­­oxy­eth­yl)-3-(carboxyl­atometh­yl)-2-ethyl­benzimidazol-1-ium monohydrate

aKey Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: zhangnwnu@126.com

(Received 11 March 2013; accepted 12 March 2013; online 16 March 2013)

In the title compound, C14H16N2O4·H2O, three substituent groups are located on the same side of the benzimidazole ring plane. In the crystal, O—H⋯O hydrogen bonds and ππ stacking between parallel imidazole rings [centroid–centroid distance = 3.858 (4) Å] link the mol­ecules into a three-dimensional supra­molecular structure.

Related literature

For general background to supra­molecular coordination complexes, see: Chakrabarty et al. (2011[Chakrabarty, R., Mukherjee, P.-S. & Stang, P. (2011). Chem. Rev. 111, 6810-6918.]); Cook et al. (2012[Cook, T. R., Zheng, Y.-R. & Stang, P. (2012). Chem. Rev. 113, 734-777.]); Wang et al. (2009[Wang, K.-F., Jian, F.-F., Zhuang, R.-R. & Xiao, H.-L. (2009). Cryst. Growth Des. 9, 3934-3940.], 2010[Wang, X.-J., Cen, Z.-M., Ni, Q.-L., Jiang, X.-F., Lian, H.-C., Gui, L.-C., Zou, H.-H. & Wang, Z.-Y. (2010). Cryst. Growth Des. 10, 2960-2968.]). For related structures, see: Wei et al. (2012[Wei, T.-B., Dang, J.-P., Lin, Q., Yao, H., Liu, Y., Zhang, W.-Q., Ming, J.-J. & Zhang, Y.-M. (2012). Sci. China Ser. B, 55, 2554-2561.]); Chen & Huang (2006[Chen, D.-B. & Huang, L. (2006). Acta Cryst. E62, o4686-o4688.]); Wu et al. (2012[Wu, H.-L., Wang, K.-T., Liu, B., Kou, F., Jia, F., Yuan, J.-K. & Bai, Y.-Y. (2012). Inorg. Chim. Acta 384, 302-308.]).

[Scheme 1]

Experimental

Crystal data
  • C14H16N2O4·H2O

  • Mr = 294.30

  • Triclinic, [P \overline 1]

  • a = 8.286 (7) Å

  • b = 9.041 (8) Å

  • c = 10.629 (9) Å

  • α = 69.905 (7)°

  • β = 69.096 (7)°

  • γ = 79.082 (8)°

  • V = 696.6 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 296 K

  • 0.26 × 0.23 × 0.22 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.973, Tmax = 0.977

  • 5039 measured reflections

  • 2551 independent reflections

  • 1888 reflections with I > 2σ(I)

  • Rint = 0.022

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.102

  • S = 1.07

  • 2551 reflections

  • 200 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3A⋯O1i 0.82 1.69 2.474 (2) 160
O5—H1W⋯O4ii 0.96 (3) 1.89 (3) 2.841 (3) 168 (2)
O5—H2W⋯O2i 0.90 (3) 1.96 (3) 2.851 (3) 176 (3)
Symmetry codes: (i) -x, -y+2, -z+1; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Benzimidazole and its derivatives are strongly coordinating agents and form stable complexes with various metals, which find various application in supramolecular coordination complexes, catalytic systems and soft materials (Chakrabarty et al., 2011; Cook et al., 2012; Wang et al., 2009; Wei et al., 2012). Meanwhile, the coordination chemistry of dicarboxylates has gained great attention for a variety of reasons, such as good conformation freedom, various coordination modes and so on (Wang et al., 2010; Wu et al., 2012). Herein we report the crystal structure of 1-(2-acetoxy)-3-(3-propionyloxy)-2-ethyl-3H-benzimidazolium salt and the molecular structure is shown in Fig 1. In the imidazolium ring, the bond lenghs range from 1.338 (2) to 1.397 (2) Å, in good agreement with the presence of conjugated double bonds and indicating a zwitterionic structure (Chen & Huang, 2006). In the U-shaped molecule, the two carboxyl group run almost perpendicular to the benzimidazolium plane in the same orientation. The N1—C10—C11 and N2—C12—C13 angles are 112.57 (14) and 113.06 (15)°, respectively. A dimer is formed by benzimidazolium salt connected to neighboring molecule through O3—H3A ···O1 hydrogen bonds (Fig 2). In addition, the dimer makes full use of two water molecules as bridging molecules to form various O—H···O hydrogen bonds to generate the wide hydrogen-bond ribbon (Fig 3). Obviously, water molecules, as a kind of linking unit, play an important role in constructing this structure. The distance between the donor and acceptor of the hydrogen bond is in the range of 2.474 (2)–2.851 (3) Å. π-π stacking is observed between parallel imidazole rings of adjacent molecules [1-x, 2-y, -z], the centroids distance being 3.858 (4) Å.

Related literature top

For general background to supramolecular coordination complexes, see: Chakrabarty et al. (2011); Cook et al. (2012); Wang et al. (2009, 2010). For related structures, see: Wei et al. (2012); Chen & Huang (2006); Wu et al. (2012).

Experimental top

1-(2-Acetoxy)-3-(3-propionyloxy)-2-ethyl-3H-benzimidazolium salt (0.2 mmol, 0.0552 g) was dissolved in distilled water. Colorless block crystals separated after several weeks.

Refinement top

Water H atoms were located in a difference Fourier map and refined isotropically. Other H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 and O—H = 0.82 Å, Uiso(H) = 1.5Ueq(C,O).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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
[Figure 1] Fig. 1. The molecular structure of the title compound with atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. Hydrogen-bonded linking pattern of the wide hydrogen-bonded ribbon in the crystal structure of the title compound.
[Figure 3] Fig. 3. Packing diagram of the title compound. All hydrogen atoms bonded to carbon are omitted for clarity.
1-(2-Carboxyethyl)-3-(carboxylatomethyl)-2-ethylbenzimidazol-1-ium monohydrate top
Crystal data top
C14H16N2O4·H2OZ = 2
Mr = 294.30F(000) = 312
Triclinic, P1Dx = 1.403 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.286 (7) ÅCell parameters from 1681 reflections
b = 9.041 (8) Åθ = 2.4–26.1°
c = 10.629 (9) ŵ = 0.11 mm1
α = 69.905 (7)°T = 296 K
β = 69.096 (7)°Block, colourless
γ = 79.082 (8)°0.26 × 0.23 × 0.22 mm
V = 696.6 (10) Å3
Data collection top
Bruker APEXII CCD
diffractometer
2551 independent reflections
Radiation source: fine-focus sealed tube1888 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
ϕ and ω scansθmax = 25.5°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 109
Tmin = 0.973, Tmax = 0.977k = 1010
5039 measured reflectionsl = 1212
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.102H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0456P)2 + 0.0692P]
where P = (Fo2 + 2Fc2)/3
2551 reflections(Δ/σ)max < 0.001
200 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C14H16N2O4·H2Oγ = 79.082 (8)°
Mr = 294.30V = 696.6 (10) Å3
Triclinic, P1Z = 2
a = 8.286 (7) ÅMo Kα radiation
b = 9.041 (8) ŵ = 0.11 mm1
c = 10.629 (9) ÅT = 296 K
α = 69.905 (7)°0.26 × 0.23 × 0.22 mm
β = 69.096 (7)°
Data collection top
Bruker APEXII CCD
diffractometer
2551 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
1888 reflections with I > 2σ(I)
Tmin = 0.973, Tmax = 0.977Rint = 0.022
5039 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.102H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.18 e Å3
2551 reflectionsΔρmin = 0.23 e Å3
200 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
xyzUiso*/Ueq
C10.2641 (2)1.08245 (19)0.06635 (18)0.0295 (4)
C20.2190 (2)1.1649 (2)0.05422 (18)0.0358 (4)
H20.20431.27470.08370.043*
C30.1973 (2)1.0757 (2)0.12773 (19)0.0420 (5)
H30.16761.12650.20960.050*
C40.2185 (3)0.9111 (2)0.0833 (2)0.0423 (5)
H40.20190.85550.13630.051*
C50.2629 (2)0.8285 (2)0.03621 (19)0.0388 (5)
H50.27670.71880.06570.047*
C60.2861 (2)0.91826 (19)0.11035 (17)0.0309 (4)
C70.3413 (2)1.0071 (2)0.26096 (19)0.0333 (4)
C80.3829 (3)1.0131 (2)0.3834 (2)0.0455 (5)
H8A0.45891.09700.35220.055*
H8B0.44490.91420.41950.055*
C90.2221 (3)1.0414 (3)0.5024 (2)0.0526 (6)
H9A0.15721.13660.46630.079*
H9B0.25651.05160.57600.079*
H9C0.15130.95390.53960.079*
C100.2867 (2)1.2987 (2)0.1588 (2)0.0375 (5)
H10A0.32671.36400.06130.045*
H10B0.36181.30960.20670.045*
C110.1029 (3)1.3575 (2)0.22808 (19)0.0371 (4)
C120.3833 (2)0.7124 (2)0.30663 (19)0.0417 (5)
H12A0.48300.71230.33420.050*
H12B0.41720.64950.24220.050*
C130.2397 (2)0.63694 (19)0.43592 (19)0.0370 (4)
H13A0.21730.68980.50660.044*
H13B0.13470.65000.41130.044*
C140.2846 (3)0.4640 (2)0.4969 (2)0.0388 (5)
N10.29992 (18)1.13350 (15)0.16246 (15)0.0312 (4)
N20.33392 (18)0.87598 (16)0.23231 (15)0.0334 (4)
O10.09505 (19)1.48021 (15)0.26178 (15)0.0534 (4)
O20.01868 (18)1.28600 (16)0.24520 (16)0.0548 (4)
O30.1787 (2)0.38995 (15)0.61738 (15)0.0562 (4)
H3A0.09960.45230.64530.084*
O40.41378 (18)0.39251 (15)0.43815 (15)0.0523 (4)
O50.3224 (3)0.5657 (2)0.8276 (2)0.0651 (5)
H1W0.405 (4)0.594 (3)0.734 (3)0.097 (10)*
H2W0.230 (4)0.614 (4)0.800 (3)0.114 (12)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0273 (10)0.0276 (9)0.0312 (9)0.0028 (7)0.0062 (7)0.0088 (7)
C20.0375 (11)0.0312 (9)0.0334 (10)0.0035 (8)0.0093 (8)0.0047 (8)
C30.0484 (13)0.0456 (11)0.0298 (10)0.0060 (9)0.0126 (9)0.0072 (8)
C40.0490 (13)0.0449 (11)0.0365 (11)0.0089 (9)0.0086 (9)0.0187 (9)
C50.0426 (11)0.0280 (9)0.0412 (11)0.0042 (8)0.0047 (9)0.0129 (8)
C60.0280 (10)0.0293 (9)0.0294 (9)0.0021 (7)0.0054 (7)0.0055 (7)
C70.0268 (10)0.0361 (10)0.0349 (10)0.0004 (7)0.0099 (8)0.0094 (8)
C80.0450 (12)0.0533 (12)0.0434 (11)0.0027 (9)0.0218 (10)0.0133 (9)
C90.0569 (14)0.0669 (14)0.0397 (11)0.0077 (11)0.0166 (10)0.0200 (10)
C100.0400 (11)0.0311 (9)0.0450 (11)0.0064 (8)0.0130 (9)0.0141 (8)
C110.0427 (12)0.0296 (10)0.0349 (10)0.0028 (9)0.0103 (9)0.0069 (8)
C120.0397 (11)0.0323 (10)0.0416 (11)0.0075 (8)0.0123 (9)0.0030 (8)
C130.0397 (11)0.0306 (10)0.0382 (10)0.0002 (8)0.0121 (9)0.0090 (8)
C140.0432 (12)0.0324 (10)0.0389 (11)0.0001 (9)0.0140 (9)0.0091 (8)
N10.0322 (8)0.0284 (8)0.0343 (8)0.0022 (6)0.0113 (7)0.0101 (6)
N20.0350 (9)0.0286 (8)0.0322 (8)0.0015 (6)0.0116 (7)0.0050 (6)
O10.0616 (10)0.0376 (8)0.0585 (9)0.0083 (7)0.0041 (7)0.0246 (7)
O20.0385 (9)0.0531 (9)0.0754 (11)0.0040 (7)0.0103 (7)0.0303 (8)
O30.0669 (11)0.0318 (7)0.0469 (8)0.0043 (7)0.0031 (8)0.0036 (6)
O40.0472 (9)0.0376 (8)0.0580 (9)0.0093 (7)0.0098 (7)0.0111 (7)
O50.0661 (12)0.0636 (11)0.0644 (12)0.0109 (9)0.0241 (11)0.0227 (9)
Geometric parameters (Å, º) top
C1—C21.385 (3)C9—H9C0.9600
C1—N11.392 (2)C10—N11.464 (2)
C1—C61.392 (3)C10—C111.518 (3)
C2—C31.372 (3)C10—H10A0.9700
C2—H20.9300C10—H10B0.9700
C3—C41.395 (3)C11—O21.225 (2)
C3—H30.9300C11—O11.262 (2)
C4—C51.373 (3)C12—N21.475 (2)
C4—H40.9300C12—C131.505 (3)
C5—C61.387 (3)C12—H12A0.9700
C5—H50.9300C12—H12B0.9700
C6—N21.397 (2)C13—C141.503 (3)
C7—N21.338 (2)C13—H13A0.9700
C7—N11.344 (2)C13—H13B0.9700
C7—C81.481 (3)C14—O41.221 (2)
C8—C91.527 (3)C14—O31.300 (2)
C8—H8A0.9700O3—H3A0.8200
C8—H8B0.9700O5—H1W0.96 (3)
C9—H9A0.9600O5—H2W0.90 (3)
C9—H9B0.9600
C2—C1—N1131.62 (16)N1—C10—C11112.57 (14)
C2—C1—C6121.81 (16)N1—C10—H10A109.1
N1—C1—C6106.55 (15)C11—C10—H10A109.1
C3—C2—C1116.25 (17)N1—C10—H10B109.1
C3—C2—H2121.9C11—C10—H10B109.1
C1—C2—H2121.9H10A—C10—H10B107.8
C2—C3—C4121.97 (18)O2—C11—O1127.11 (18)
C2—C3—H3119.0O2—C11—C10119.49 (17)
C4—C3—H3119.0O1—C11—C10113.39 (17)
C5—C4—C3122.09 (18)N2—C12—C13113.06 (15)
C5—C4—H4119.0N2—C12—H12A109.0
C3—C4—H4119.0C13—C12—H12A109.0
C4—C5—C6116.14 (17)N2—C12—H12B109.0
C4—C5—H5121.9C13—C12—H12B109.0
C6—C5—H5121.9H12A—C12—H12B107.8
C5—C6—C1121.74 (17)C14—C13—C12111.66 (16)
C5—C6—N2131.85 (16)C14—C13—H13A109.3
C1—C6—N2106.40 (15)C12—C13—H13A109.3
N2—C7—N1108.99 (16)C14—C13—H13B109.3
N2—C7—C8125.90 (16)C12—C13—H13B109.3
N1—C7—C8125.09 (17)H13A—C13—H13B107.9
C7—C8—C9112.83 (17)O4—C14—O3119.89 (17)
C7—C8—H8A109.0O4—C14—C13122.94 (17)
C9—C8—H8A109.0O3—C14—C13117.17 (17)
C7—C8—H8B109.0C7—N1—C1109.03 (15)
C9—C8—H8B109.0C7—N1—C10126.07 (16)
H8A—C8—H8B107.8C1—N1—C10124.85 (14)
C8—C9—H9A109.5C7—N2—C6109.03 (14)
C8—C9—H9B109.5C7—N2—C12126.86 (16)
H9A—C9—H9B109.5C6—N2—C12123.88 (15)
C8—C9—H9C109.5C14—O3—H3A109.5
H9A—C9—H9C109.5H1W—O5—H2W95 (2)
H9B—C9—H9C109.5
N1—C1—C2—C3178.24 (17)C8—C7—N1—C1178.25 (16)
C6—C1—C2—C30.0 (3)N2—C7—N1—C10177.63 (15)
C1—C2—C3—C40.3 (3)C8—C7—N1—C100.7 (3)
C2—C3—C4—C50.3 (3)C2—C1—N1—C7178.66 (18)
C3—C4—C5—C60.2 (3)C6—C1—N1—C70.20 (18)
C4—C5—C6—C10.5 (3)C2—C1—N1—C103.8 (3)
C4—C5—C6—N2178.59 (18)C6—C1—N1—C10177.77 (15)
C2—C1—C6—C50.4 (3)C11—C10—N1—C794.1 (2)
N1—C1—C6—C5179.05 (15)C11—C10—N1—C183.0 (2)
C2—C1—C6—N2178.87 (16)N1—C7—N2—C60.06 (19)
N1—C1—C6—N20.23 (17)C8—C7—N2—C6178.38 (16)
N2—C7—C8—C9100.2 (2)N1—C7—N2—C12174.64 (15)
N1—C7—C8—C977.8 (2)C8—C7—N2—C127.0 (3)
N1—C10—C11—O219.1 (2)C5—C6—N2—C7178.99 (18)
N1—C10—C11—O1161.19 (15)C1—C6—N2—C70.18 (19)
N2—C12—C13—C14171.70 (16)C5—C6—N2—C124.2 (3)
C12—C13—C14—O47.5 (3)C1—C6—N2—C12174.96 (15)
C12—C13—C14—O3172.71 (17)C13—C12—N2—C785.2 (2)
N2—C7—N1—C10.09 (19)C13—C12—N2—C6101.0 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O1i0.821.692.474 (2)160
O5—H1W···O4ii0.96 (3)1.89 (3)2.841 (3)168 (2)
O5—H2W···O2i0.90 (3)1.96 (3)2.851 (3)176 (3)
Symmetry codes: (i) x, y+2, z+1; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC14H16N2O4·H2O
Mr294.30
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)8.286 (7), 9.041 (8), 10.629 (9)
α, β, γ (°)69.905 (7), 69.096 (7), 79.082 (8)
V3)696.6 (10)
Z2
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.26 × 0.23 × 0.22
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.973, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections
5039, 2551, 1888
Rint0.022
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.102, 1.07
No. of reflections2551
No. of parameters200
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.18, 0.23

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O1i0.821.692.474 (2)159.6
O5—H1W···O4ii0.96 (3)1.89 (3)2.841 (3)168 (2)
O5—H2W···O2i0.90 (3)1.96 (3)2.851 (3)176 (3)
Symmetry codes: (i) x, y+2, z+1; (ii) x+1, y+1, z+1.
 

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 21064006, 21161018 and 21262032), the Program for Changjiang Scholars and Innovative Research Teams in Universities of the Ministry of Education of China (No. IRT1177), the Natural Science Foundation of Gansu Province (No. 1010RJZA018), the Youth Foundation of Gansu Province (No. 1208RJYA048) and NWNU-LKQN-11–32.

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