metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Tri­aqua­di­chlorido[5-(4-pyridinio)tetra­zolato-κN2]cobalt(II) monohydrate

aOrdered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China
*Correspondence e-mail: fudavid88@yahoo.com.cn

(Received 18 June 2009; accepted 24 June 2009; online 1 July 2009)

The title compound, [CoCl2(C6H5N5)(H2O)3]·H2O, was synthesized by hydro­thermal reaction of CoCl2 with 4-(2H-tetra­zol-5-yl)pyridine. The CoII cation is coordinated by two Cl ions, one N atom from the 5-(4-pyridinio)tetra­zolate zwitterion and three O atoms from three water mol­ecules in a distorted octa­hedral geometry. In the crystal, mol­ecules are linked into a three-dimensional network by N—H⋯Cl hydrogen bonds and O—H⋯O/N/Cl hydrogen bonds involv­ing both coordinated and uncoordinated water mol­ecules. Strong ππ stacking is present between parallel pyridinium and tetra­zolate rings [centroid–centroid distances = 3.411 (2) and 3.436 (2) Å].

Related literature

For general background to the chemistry of tetra­zole derivatives, see: Fu et al. (2007[Fu, D.-W., Song, Y.-M., Wang, G.-X., Ye, Q., Xiong, R.-G., Akutagawa, T., Nakamura, T., Chan, P. W. H. & Huang, S.-P. (2007). J. Am. Chem. Soc. 129, 5346-5347.], 2008[Fu, D.-W., Zhang, W. & Xiong, R.-G. (2008). Cryst. Growth Des. 8, 3461-3464.]); Huang et al. (1999[Huang, S.-P.-D., Xiong, R.-G., Han, J.-D. & Weiner, B. R. (1999). Inorg. Chim. Acta, 294, 95-98.]); Liu et al. (1999[Liu, C.-M., Yu, Z., Xiong, R.-G., Liu, K. & You, X.-Z. (1999). Inorg. Chem. Commun. 2, 31-34.]); Wang et al. (2005[Wang, X.-S., Tang, Y.-Z., Huang, X.-F., Qu, Z.-R., Che, C.-M., Chan, C. W. H. & Xiong, R.-G. (2005). Inorg. Chem. 44, 5278-5285.]). For the crystal structures of related compounds, see: Dai & Fu (2008[Dai, W. & Fu, D.-W. (2008). Acta Cryst. E64, o1444.]); Wen (2008[Wen, X.-C. (2008). Acta Cryst. E64, m768.]); Wittenberger & Donner (1993[Wittenberger, S. J. & Donner, B. G. (1993). J. Org. Chem. 58, 4139-4141.]).

[Scheme 1]

Experimental

Crystal data
  • [CoCl2(C6H5N5)(H2O)3]·H2O

  • Mr = 349.04

  • Triclinic, [P \overline 1]

  • a = 6.4900 (13) Å

  • b = 9.842 (2) Å

  • c = 11.159 (2) Å

  • α = 110.72 (3)°

  • β = 97.05 (3)°

  • γ = 106.27 (3)°

  • V = 620.1 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.83 mm−1

  • T = 298 K

  • 0.15 × 0.15 × 0.10 mm

Data collection
  • Rigaku Mercury2 diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.762, Tmax = 0.841

  • 6551 measured reflections

  • 2842 independent reflections

  • 2619 reflections with I > 2σ(I)

  • Rint = 0.019

Refinement
  • R[F2 > 2σ(F2)] = 0.026

  • wR(F2) = 0.080

  • S = 1.18

  • 2842 reflections

  • 163 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.49 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3W—H3WA⋯O4Wi 0.95 1.92 2.858 (3) 173
O3W—H3WB⋯O4Wii 0.86 1.91 2.761 (2) 170
O1W—H1WB⋯N4iii 0.88 2.01 2.848 (2) 157
O2W—H2WA⋯N2iv 0.83 2.24 2.999 (2) 153
O4W—H4WA⋯N5v 0.83 2.11 2.935 (3) 173
N1—H1A⋯Cl2v 0.86 2.41 3.180 (2) 149
O1W—H1WA⋯Cl2vi 0.94 2.32 3.254 (2) 174
O2W—H2WB⋯Cl1vii 0.91 2.42 3.300 (2) 163
O4W—H4WB⋯Cl1iv 0.88 2.38 3.249 (2) 168
Symmetry codes: (i) -x, -y+1, -z+1; (ii) x, y-1, z-1; (iii) -x+1, -y+1, -z; (iv) -x+1, -y+1, -z+1; (v) -x+1, -y+2, -z+1; (vi) x+1, y, z; (vii) x-1, y, z.

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; 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

The tetrazole functional group has found a wide range of applications in coordination chemistry as a ligand, in medicinal chemistry as a metabolically stable surrogate for the carboxylic acid group, and in materials science as a high density energy materials, dielectric and luminescence materials (Wang et al., 2005; Fu et al., 2008; Fu et al., 2007; Huang et al., 1999; Liu et al., 1999; Wittenberger et al.,1993). We report here the crystal structure of the title compound, triaqua-dichloro-[4-(2H-tetrazol)pyridinum]cobalt(II) monohydrate.

The CoII cation is coordinated by two Cl- ions, one N atom from the pyridinio-4-(2H-tetrazolate) zwitterion and three O atoms from three water molecules in a distorted octahedral geometry. The pyridine N atom of the organic ligand is protonated. The pyridinium and tetrazolate rings are almost coplanar, with a dihedral angle of 3.7 (1)°. The geometric parameters of the tetrazolate ring are comparable to those in related molecules (Wittenberger et al., 1993; Dai & Fu 2008; Wen 2008).

The molecules are linked into a three-dimensional network by intermolecular O—H···O, O—H···N, N—H···Cl and O—H···Cl hydrogen bonds (Table 1 and Fig.2).

Related literature top

For general background to the chemistry of tetrazole derivatives, see: Fu et al. (2007, 2008); Huang et al. (1999); Liu et al. (1999); Wang et al. (2005). For the crystal structures of related compounds, see: Dai & Fu (2008); Wen (2008); Wittenberger & Donner (1993).

Experimental top

A mixture of 4-(2H-tetrazol-5-yl)pyridine (0.2 mmol), CoCl2 (0.4 mmol), distilled water (1 ml) and a few drops of HCl (6 mol/L) was sealed in a glass tube and maintained at 333 K. Pink block-shaped crystals suitable for X-ray analysis were obtained after 3 d.

Refinement top

H atoms of water molecules were located in difference Fourier maps and in the final stages of refinement they were treated as riding on the parent O atom with Uiso(H) = 1.5Ueq(O). The remaining H atoms were positioned geometrically and treated as riding, with C-H = 0.93 Å, N-H = 0.86 Å, and with Uiso(H) = 1.2Ueq(C,N).

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
[Figure 1] Fig. 1. The molecular structure of the title compound, with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed along the a axis, showing the three dimensionnal hydrogen-bonded network. H atoms not involved in hydrogen bonding (dashed line) have been omitted for clarity.
Triaquadichlorido[5-(4-pyridinio)tetrazolato-κN2]cobalt(II) monohydrate top
Crystal data top
[CoCl2(C6H5N5)(H2O)3]·H2OZ = 2
Mr = 349.04F(000) = 354
Triclinic, P1Dx = 1.869 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.4900 (13) ÅCell parameters from 2619 reflections
b = 9.842 (2) Åθ = 3.4–27.5°
c = 11.159 (2) ŵ = 1.83 mm1
α = 110.72 (3)°T = 298 K
β = 97.05 (3)°Block, pink
γ = 106.27 (3)°0.15 × 0.15 × 0.10 mm
V = 620.1 (3) Å3
Data collection top
Rigaku Mercury2
diffractometer
2842 independent reflections
Radiation source: fine-focus sealed tube2619 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.019
Detector resolution: 13.6612 pixels mm-1θmax = 27.5°, θmin = 3.4°
CCD profile fitting scansh = 88
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 1212
Tmin = 0.762, Tmax = 0.841l = 1414
6551 measured reflections
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)] = 0.026Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.080H-atom parameters constrained
S = 1.18 w = 1/[σ2(Fo2) + (0.0344P)2 + 0.391P]
where P = (Fo2 + 2Fc2)/3
2842 reflections(Δ/σ)max = 0.001
163 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.49 e Å3
Crystal data top
[CoCl2(C6H5N5)(H2O)3]·H2Oγ = 106.27 (3)°
Mr = 349.04V = 620.1 (3) Å3
Triclinic, P1Z = 2
a = 6.4900 (13) ÅMo Kα radiation
b = 9.842 (2) ŵ = 1.83 mm1
c = 11.159 (2) ÅT = 298 K
α = 110.72 (3)°0.15 × 0.15 × 0.10 mm
β = 97.05 (3)°
Data collection top
Rigaku Mercury2
diffractometer
2842 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
2619 reflections with I > 2σ(I)
Tmin = 0.762, Tmax = 0.841Rint = 0.019
6551 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0260 restraints
wR(F2) = 0.080H-atom parameters constrained
S = 1.18Δρmax = 0.34 e Å3
2842 reflectionsΔρmin = 0.49 e Å3
163 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
N50.6736 (3)0.84317 (19)0.28889 (17)0.0224 (4)
C60.6810 (3)0.8500 (2)0.41148 (19)0.0188 (4)
N10.8708 (3)1.2651 (2)0.74897 (19)0.0281 (4)
H1A0.90981.35030.81830.034*
N20.6143 (3)0.70917 (18)0.41274 (16)0.0192 (3)
N40.5984 (3)0.69178 (19)0.21085 (16)0.0224 (4)
C30.7487 (3)0.9955 (2)0.52968 (19)0.0183 (4)
C50.8008 (4)1.1310 (3)0.7624 (2)0.0301 (5)
H50.79521.13080.84520.036*
N30.5635 (3)0.61292 (18)0.28545 (16)0.0197 (3)
C20.8224 (3)1.1378 (2)0.5204 (2)0.0243 (4)
H20.83091.14190.43910.029*
C40.7372 (4)0.9933 (2)0.6525 (2)0.0253 (4)
H40.68680.89940.66050.030*
C10.8826 (4)1.2725 (2)0.6330 (2)0.0282 (5)
H10.93121.36820.62800.034*
Co1A0.41776 (4)0.36866 (3)0.20745 (2)0.01763 (9)
Cl20.08900 (9)0.38823 (6)0.08079 (5)0.02643 (13)
Cl10.73776 (8)0.35040 (6)0.33499 (5)0.02677 (13)
O1W0.5652 (3)0.33958 (19)0.04986 (14)0.0285 (3)
H1WA0.71730.35700.06560.043*
H1WB0.52540.35830.01970.043*
O2W0.2585 (3)0.37067 (19)0.35990 (15)0.0296 (3)
H2WA0.30370.38090.43620.044*
H2WB0.12660.38670.35660.044*
O3W0.2553 (3)0.12646 (16)0.12299 (15)0.0266 (3)
H3WA0.10360.09730.12310.040*
H3WB0.24620.08570.04000.040*
O4W0.1925 (3)0.96192 (19)0.85528 (16)0.0363 (4)
H4WA0.23061.01070.80930.054*
H4WB0.22830.88030.81400.054*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N50.0273 (9)0.0172 (8)0.0214 (8)0.0062 (7)0.0062 (7)0.0075 (7)
C60.0169 (9)0.0168 (9)0.0209 (9)0.0050 (7)0.0041 (7)0.0066 (7)
N10.0271 (9)0.0175 (8)0.0273 (9)0.0062 (7)0.0015 (7)0.0020 (7)
N20.0221 (8)0.0155 (7)0.0161 (8)0.0052 (6)0.0026 (6)0.0040 (6)
N40.0280 (9)0.0182 (8)0.0191 (8)0.0063 (7)0.0049 (7)0.0071 (7)
C30.0140 (8)0.0161 (9)0.0216 (9)0.0056 (7)0.0001 (7)0.0053 (7)
C50.0356 (12)0.0251 (11)0.0225 (10)0.0083 (9)0.0043 (9)0.0045 (9)
N30.0235 (8)0.0161 (8)0.0173 (8)0.0058 (7)0.0045 (7)0.0054 (6)
C20.0254 (10)0.0200 (10)0.0282 (11)0.0077 (8)0.0066 (8)0.0107 (8)
C40.0319 (11)0.0189 (9)0.0231 (10)0.0082 (8)0.0042 (8)0.0075 (8)
C10.0247 (10)0.0163 (9)0.0405 (13)0.0064 (8)0.0065 (9)0.0093 (9)
Co1A0.02082 (15)0.01475 (14)0.01550 (15)0.00521 (11)0.00386 (11)0.00507 (11)
Cl20.0265 (3)0.0249 (3)0.0237 (3)0.0102 (2)0.0001 (2)0.0064 (2)
Cl10.0260 (3)0.0286 (3)0.0274 (3)0.0105 (2)0.0033 (2)0.0135 (2)
O1W0.0259 (8)0.0419 (9)0.0191 (7)0.0127 (7)0.0067 (6)0.0131 (7)
O2W0.0331 (9)0.0381 (9)0.0230 (8)0.0158 (7)0.0124 (7)0.0140 (7)
O3W0.0318 (8)0.0187 (7)0.0218 (7)0.0030 (6)0.0043 (6)0.0050 (6)
O4W0.0518 (11)0.0262 (8)0.0300 (9)0.0106 (8)0.0174 (8)0.0104 (7)
Geometric parameters (Å, º) top
N5—N41.337 (2)C4—H40.93
N5—C61.340 (3)C1—H10.93
C6—N21.337 (2)Co1A—O1W2.0738 (16)
C6—C31.467 (3)Co1A—O2W2.0933 (16)
N1—C11.332 (3)Co1A—O3W2.1071 (17)
N1—C51.339 (3)Co1A—Cl12.4568 (9)
N1—H1A0.86Co1A—Cl22.5041 (9)
N2—N31.335 (2)O1W—H1WA0.94
N4—N31.323 (2)O1W—H1WB0.88
C3—C41.389 (3)O2W—H2WA0.83
C3—C21.393 (3)O2W—H2WB0.91
C5—C41.377 (3)O3W—H3WA0.94
C5—H50.93O3W—H3WB0.86
N3—Co1A2.1153 (18)O4W—H4WA0.83
C2—C11.379 (3)O4W—H4WB0.88
C2—H20.93
N4—N5—C6104.78 (16)C2—C1—H1120.1
N2—C6—N5112.14 (17)O1W—Co1A—O2W173.47 (6)
N2—C6—C3124.23 (18)O1W—Co1A—O3W87.50 (7)
N5—C6—C3123.61 (17)O2W—Co1A—O3W86.15 (7)
C1—N1—C5122.93 (19)O1W—Co1A—N392.57 (7)
C1—N1—H1A118.5O2W—Co1A—N393.86 (7)
C5—N1—H1A118.5O3W—Co1A—N3176.39 (6)
N3—N2—C6103.82 (16)O1W—Co1A—Cl189.28 (5)
N3—N4—N5108.68 (16)O2W—Co1A—Cl189.42 (5)
C4—C3—C2118.98 (19)O3W—Co1A—Cl192.27 (6)
C4—C3—C6120.36 (18)N3—Co1A—Cl191.34 (6)
C2—C3—C6120.65 (19)O1W—Co1A—Cl291.67 (5)
N1—C5—C4119.4 (2)O2W—Co1A—Cl289.64 (5)
N1—C5—H5120.3O3W—Co1A—Cl287.85 (6)
C4—C5—H5120.3N3—Co1A—Cl288.54 (6)
N4—N3—N2110.58 (15)Cl1—Co1A—Cl2179.04 (2)
N4—N3—Co1A123.34 (12)Co1A—O1W—H1WA118.8
N2—N3—Co1A125.83 (13)Co1A—O1W—H1WB125.5
C1—C2—C3119.3 (2)H1WA—O1W—H1WB108.6
C1—C2—H2120.4Co1A—O2W—H2WA131.9
C3—C2—H2120.4Co1A—O2W—H2WB120.0
C5—C4—C3119.6 (2)H2WA—O2W—H2WB106.3
C5—C4—H4120.2Co1A—O3W—H3WA112.7
C3—C4—H4120.2Co1A—O3W—H3WB112.6
N1—C1—C2119.8 (2)H3WA—O3W—H3WB100.6
N1—C1—H1120.1H4WA—O4W—H4WB98.3
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3W—H3WA···O4Wi0.951.922.858 (3)173
O3W—H3WB···O4Wii0.861.912.761 (2)170
O1W—H1WB···N4iii0.882.012.848 (2)157
O2W—H2WA···N2iv0.832.242.999 (2)153
O4W—H4WA···N5v0.832.112.935 (3)173
N1—H1A···Cl2v0.862.413.180 (2)149
O1W—H1WA···Cl2vi0.942.323.254 (2)174
O2W—H2WB···Cl1vii0.912.423.300 (2)163
O4W—H4WB···Cl1iv0.882.383.249 (2)168
Symmetry codes: (i) x, y+1, z+1; (ii) x, y1, z1; (iii) x+1, y+1, z; (iv) x+1, y+1, z+1; (v) x+1, y+2, z+1; (vi) x+1, y, z; (vii) x1, y, z.

Experimental details

Crystal data
Chemical formula[CoCl2(C6H5N5)(H2O)3]·H2O
Mr349.04
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)6.4900 (13), 9.842 (2), 11.159 (2)
α, β, γ (°)110.72 (3), 97.05 (3), 106.27 (3)
V3)620.1 (3)
Z2
Radiation typeMo Kα
µ (mm1)1.83
Crystal size (mm)0.15 × 0.15 × 0.10
Data collection
DiffractometerRigaku Mercury2
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.762, 0.841
No. of measured, independent and
observed [I > 2σ(I)] reflections
6551, 2842, 2619
Rint0.019
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.026, 0.080, 1.18
No. of reflections2842
No. of parameters163
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.49

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

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3W—H3WA···O4Wi0.951.922.858 (3)173
O3W—H3WB···O4Wii0.861.912.761 (2)170
O1W—H1WB···N4iii0.882.012.848 (2)157
O2W—H2WA···N2iv0.832.242.999 (2)153
O4W—H4WA···N5v0.832.112.935 (3)173
N1—H1A···Cl2v0.862.413.180 (2)149
O1W—H1WA···Cl2vi0.942.323.254 (2)174
O2W—H2WB···Cl1vii0.912.423.300 (2)163
O4W—H4WB···Cl1iv0.882.383.249 (2)168
Symmetry codes: (i) x, y+1, z+1; (ii) x, y1, z1; (iii) x+1, y+1, z; (iv) x+1, y+1, z+1; (v) x+1, y+2, z+1; (vi) x+1, y, z; (vii) x1, y, z.
 

Acknowledgements

This work was supported by a start-up grant from Southeast University to Professor Ren-Gen Xiong.

References

First citationDai, W. & Fu, D.-W. (2008). Acta Cryst. E64, o1444.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationFu, D.-W., Song, Y.-M., Wang, G.-X., Ye, Q., Xiong, R.-G., Akutagawa, T., Nakamura, T., Chan, P. W. H. & Huang, S.-P. (2007). J. Am. Chem. Soc. 129, 5346–5347.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationFu, D.-W., Zhang, W. & Xiong, R.-G. (2008). Cryst. Growth Des. 8, 3461–3464.  Web of Science CSD CrossRef CAS Google Scholar
First citationHuang, S.-P.-D., Xiong, R.-G., Han, J.-D. & Weiner, B. R. (1999). Inorg. Chim. Acta, 294, 95-98.  Web of Science CSD CrossRef CAS Google Scholar
First citationLiu, C.-M., Yu, Z., Xiong, R.-G., Liu, K. & You, X.-Z. (1999). Inorg. Chem. Commun. 2, 31–34.  Web of Science CSD CrossRef CAS Google Scholar
First citationRigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationWang, X.-S., Tang, Y.-Z., Huang, X.-F., Qu, Z.-R., Che, C.-M., Chan, C. W. H. & Xiong, R.-G. (2005). Inorg. Chem. 44, 5278–5285.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationWen, X.-C. (2008). Acta Cryst. E64, m768.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationWittenberger, S. J. & Donner, B. G. (1993). J. Org. Chem. 58, 4139–4141.  CrossRef CAS Web of Science Google Scholar

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