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ISSN: 2056-9890

2,2′-[1-(2,4,6-Tri­chloro­phenyl)-1H-1,2,4-triazole-3,5-diyl]diphenol

aOrdered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China, and bDepartment of Chemistry, Key Laboratory of Medicinal Chemistry for Natural Resources of the Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
*Correspondence e-mail: chmsunbw@seu.edu.cn

(Received 27 December 2007; accepted 15 January 2008; online 23 January 2008)

The title compound, C20H12Cl3N3O2, was synthesized by the reaction of 2-(2-hydroxy­phen­yl)benz[e][1,3]oxazin-4-one with 2,4,6-trichloro­phenyl­hydrazine in ethanol. The trichloro­phenyl ring is nearly perpendicular to the triazole plane [dihedral angle 80.56 (8)°], whereas the two hydroxy­phenyl rings are approximately coplanar with the triazole ring [dihedral angles of 2.79 (12) and 8.00 (14)°]. Intra­molecular O—H⋯N hydrogen bonding is observed between the hydroxy­phenyl and triazole rings.

Related literature

For general background, see: Nisbet-Brown et al. (2003[Nisbet-Brown, E., Olivieri, N. F., Giardina, P. J., Grady, R. W., Neufeld, E. J., Sechaud, R., Krebs-Brown, A. J., Anderson, J. R., Alberti, D., Sizer, K. C. & Nathan, D. G. (2003). Lancet, 361, 1597-1602.]); Steinhauser et al. (2004[Steinhauser, S., Heinz, U., Bartholomä, M., Weyhermüller, T., Nick, H. & Hegetschweiler, K. (2004). Eur. J. Inorg. Chem. pp. 4177-4192.]).

[Scheme 1]

Experimental

Crystal data
  • C20H12Cl3N3O2

  • Mr = 432.68

  • Monoclinic, P 21 /c

  • a = 14.328 (3) Å

  • b = 12.021 (2) Å

  • c = 12.014 (2) Å

  • β = 104.99 (3)°

  • V = 1998.7 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.48 mm−1

  • T = 293 (2) K

  • 0.20 × 0.20 × 0.18 mm

Data collection
  • Rigaku SCXmini diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Version 1.4.0. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.907, Tmax = 0.915

  • 16254 measured reflections

  • 3501 independent reflections

  • 3052 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.104

  • S = 1.11

  • 3501 reflections

  • 261 parameters

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

  • Δρmax = 0.35 e Å−3

  • Δρmin = −0.35 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1A⋯N3 0.83 (3) 1.89 (3) 2.640 (3) 149 (3)
O2—H2A⋯N2 0.81 (2) 1.94 (2) 2.648 (3) 146 (3)

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Version 1.4.0. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL/PC; molecular graphics: SHELXTL/PC; software used to prepare material for publication: SHELXTL/PC.

Supporting information


Comment top

3,5-Bis(2-hydroxyphenyl)-1-phenyl-1,2,4-triazole core has been successfully used a motif for the development of biologically interesting molecules, including active iron chelator (Nisbet-Brown et al., 2003; Steinhauser et al., 2004). We report here the crystal structure of the title triazole compound.

In the title molecule (Fig. 1), 3-(2-hydroxyphenyl) is almost co-planar with 1,2,4-triazole ring, dihedral angle being 2.79 (12)°. The 5-(2-hydroxyphenyl) ring forms a dihedral angle of 9.70 (13)° with triazole plane. The trichlorophenyl is nearly perpendicular to the triazole plane with a dihedral angle of 80.56 (8)°. Intra-molecular N—H···O hydrogen bonding is observed between hydroxyphenyl and triazole rings (Table 1).

Related literature top

For general background, see: Nisbet-Brown et al. (2003); Steinhauser et al. (2004).

Experimental top

2-(2-Hydroxyphenyl)benz[e][1,3]oxazin-4-one (2.4 g) was mixed with 2,4,6-trichlorophenylhydrazine (2.2 g) in ethanol (30 ml). The mixture was refluxed for 3 h, after cooling to room temperature, the mixture was poured onto water and extracted with ethyl acetate. The combined organic phases were dried over sodium sulfate and concentrated on a rotary evaporator. The title compound was crystallized from methanol. The colourless crystals were obtained by slow evaporation of methanol.

Refinement top

H atoms bound to carbon were placed in calculated positions and refined in riding mode with C—H = 0.93 Å and Uiso(H)=1.2Ueq(C). Hydroxyl H atoms were located in a difference Fourier map and refined isotropically.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005; data reduction: CrystalClear (Rigaku, 2005; program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2008); program(s) used to refine structure: SHELXTL/PC (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
2,2'-[1-(2,4,6-Trichlorophenyl)-1H-1,2,4-triazole-3,5-diyl]diphenol top
Crystal data top
C20H12Cl3N3O2F(000) = 880
Mr = 432.68Dx = 1.438 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5847 reflections
a = 14.328 (3) Åθ = 3.0–28.4°
b = 12.021 (2) ŵ = 0.48 mm1
c = 12.014 (2) ÅT = 293 K
β = 104.99 (3)°Block, colourless
V = 1998.7 (7) Å30.20 × 0.20 × 0.18 mm
Z = 4
Data collection top
Rigaku SCXmini
diffractometer
3501 independent reflections
Radiation source: fine-focus sealed tube3052 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
Detector resolution: 8.192 pixels mm-1θmax = 25.0°, θmin = 3.1°
ω scansh = 1717
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 1414
Tmin = 0.907, Tmax = 0.915l = 1414
16254 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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.11 w = 1/[σ2(Fo2) + (0.034P)2 + 0.892P]
where P = (Fo2 + 2Fc2)/3
3501 reflections(Δ/σ)max < 0.001
261 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = 0.35 e Å3
Crystal data top
C20H12Cl3N3O2V = 1998.7 (7) Å3
Mr = 432.68Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.328 (3) ŵ = 0.48 mm1
b = 12.021 (2) ÅT = 293 K
c = 12.014 (2) Å0.20 × 0.20 × 0.18 mm
β = 104.99 (3)°
Data collection top
Rigaku SCXmini
diffractometer
3501 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
3052 reflections with I > 2σ(I)
Tmin = 0.907, Tmax = 0.915Rint = 0.047
16254 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.11Δρmax = 0.36 e Å3
3501 reflectionsΔρmin = 0.35 e Å3
261 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
Cl10.25005 (6)0.25222 (6)0.53114 (7)0.0819 (3)
Cl20.36388 (5)0.15110 (5)0.40863 (6)0.0679 (2)
Cl30.49510 (6)0.22786 (7)0.25494 (7)0.0814 (2)
N10.25668 (12)0.00229 (15)0.52989 (14)0.0448 (4)
N20.29844 (12)0.00432 (15)0.64746 (14)0.0452 (4)
N30.14978 (11)0.08336 (15)0.60312 (14)0.0437 (4)
C10.33274 (16)0.04839 (17)0.89318 (18)0.0460 (5)
C20.34437 (19)0.0687 (2)1.0104 (2)0.0625 (6)
H2C0.40180.04901.06320.075*
C30.2707 (2)0.1181 (2)1.0485 (2)0.0678 (7)
H3B0.27880.13051.12680.081*
C40.1850 (2)0.1491 (2)0.9706 (2)0.0638 (7)
H4A0.13600.18230.99670.077*
C50.17289 (17)0.13019 (19)0.8534 (2)0.0531 (6)
H5A0.11550.15130.80140.064*
C60.24623 (14)0.07958 (17)0.81220 (17)0.0410 (5)
C70.23151 (14)0.05618 (16)0.68776 (17)0.0399 (4)
C80.16669 (14)0.04599 (17)0.50442 (18)0.0422 (5)
C90.09851 (15)0.06060 (19)0.38957 (18)0.0483 (5)
C100.01411 (16)0.1254 (2)0.3802 (2)0.0555 (6)
C110.04752 (19)0.1462 (2)0.2709 (3)0.0749 (8)
H11A0.10240.18950.26450.090*
C120.0282 (2)0.1036 (3)0.1730 (3)0.0841 (9)
H12A0.06910.12020.10120.101*
C130.0522 (2)0.0357 (3)0.1803 (2)0.0850 (9)
H13A0.06370.00450.11420.102*
C140.11476 (18)0.0154 (3)0.2880 (2)0.0698 (7)
H14A0.16870.02920.29300.084*
C150.31228 (14)0.05594 (18)0.46145 (17)0.0430 (5)
C160.36702 (15)0.00659 (18)0.40185 (17)0.0454 (5)
C170.42321 (16)0.0452 (2)0.33763 (19)0.0524 (6)
H17A0.45870.00350.29780.063*
C180.42469 (17)0.1615 (2)0.3349 (2)0.0550 (6)
C190.37295 (18)0.2260 (2)0.3944 (2)0.0609 (6)
H19A0.37580.30330.39230.073*
C200.31687 (16)0.1727 (2)0.4570 (2)0.0520 (5)
O10.01130 (13)0.16967 (17)0.47345 (18)0.0718 (5)
H1A0.032 (2)0.156 (3)0.533 (3)0.087 (10)*
O20.40802 (12)0.00300 (15)0.86177 (16)0.0593 (4)
H2A0.3949 (19)0.013 (2)0.793 (2)0.064 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0879 (5)0.0692 (5)0.1039 (6)0.0208 (4)0.0528 (5)0.0016 (4)
Cl20.0863 (5)0.0487 (3)0.0809 (5)0.0037 (3)0.0437 (4)0.0037 (3)
Cl30.0916 (5)0.0814 (5)0.0878 (5)0.0185 (4)0.0529 (4)0.0117 (4)
N10.0394 (9)0.0578 (11)0.0380 (9)0.0044 (8)0.0116 (7)0.0019 (8)
N20.0411 (9)0.0563 (11)0.0381 (9)0.0046 (8)0.0100 (7)0.0020 (8)
N30.0368 (9)0.0510 (10)0.0449 (10)0.0025 (7)0.0136 (8)0.0033 (8)
C10.0516 (12)0.0416 (11)0.0455 (12)0.0003 (9)0.0140 (10)0.0031 (9)
C20.0686 (16)0.0713 (16)0.0440 (13)0.0056 (13)0.0083 (11)0.0029 (11)
C30.091 (2)0.0722 (17)0.0421 (14)0.0006 (15)0.0210 (13)0.0036 (12)
C40.0784 (17)0.0642 (16)0.0581 (16)0.0057 (13)0.0345 (14)0.0086 (12)
C50.0543 (13)0.0559 (14)0.0511 (13)0.0070 (11)0.0176 (11)0.0018 (10)
C60.0460 (11)0.0383 (10)0.0411 (11)0.0023 (9)0.0152 (9)0.0008 (8)
C70.0383 (10)0.0419 (11)0.0409 (11)0.0005 (8)0.0130 (9)0.0016 (8)
C80.0358 (10)0.0487 (12)0.0438 (12)0.0022 (9)0.0136 (9)0.0033 (9)
C90.0389 (11)0.0603 (14)0.0441 (12)0.0057 (10)0.0079 (9)0.0071 (10)
C100.0417 (12)0.0601 (14)0.0614 (15)0.0054 (10)0.0075 (11)0.0078 (11)
C110.0527 (15)0.0833 (19)0.075 (2)0.0037 (14)0.0075 (14)0.0187 (15)
C120.0689 (19)0.114 (3)0.0552 (17)0.0103 (17)0.0095 (14)0.0228 (16)
C130.0680 (18)0.136 (3)0.0463 (16)0.0049 (18)0.0067 (13)0.0005 (16)
C140.0504 (14)0.110 (2)0.0458 (14)0.0045 (14)0.0061 (11)0.0033 (14)
C150.0380 (10)0.0542 (13)0.0371 (11)0.0028 (9)0.0102 (9)0.0043 (9)
C160.0453 (12)0.0498 (12)0.0418 (11)0.0031 (9)0.0124 (9)0.0005 (9)
C170.0521 (13)0.0618 (15)0.0476 (13)0.0048 (11)0.0210 (10)0.0042 (10)
C180.0550 (13)0.0635 (15)0.0506 (13)0.0096 (11)0.0210 (11)0.0079 (11)
C190.0673 (16)0.0496 (13)0.0704 (17)0.0009 (11)0.0262 (13)0.0083 (11)
C200.0499 (12)0.0550 (14)0.0537 (13)0.0060 (10)0.0180 (10)0.0029 (10)
O10.0472 (10)0.0926 (14)0.0714 (13)0.0185 (9)0.0078 (9)0.0004 (10)
O20.0530 (10)0.0742 (12)0.0491 (10)0.0160 (8)0.0103 (8)0.0052 (9)
Geometric parameters (Å, º) top
Cl1—C201.751 (2)C9—C141.410 (3)
Cl2—C161.740 (2)C9—C101.419 (3)
Cl3—C181.754 (2)C10—O11.371 (3)
N1—C81.374 (3)C10—C111.402 (4)
N1—N21.386 (2)C11—C121.375 (4)
N1—C151.437 (2)C11—H11A0.9300
N2—C71.335 (3)C12—C131.395 (4)
N3—C81.347 (3)C12—H12A0.9300
N3—C71.377 (3)C13—C141.392 (4)
C1—O21.378 (3)C13—H13A0.9300
C1—C21.396 (3)C14—H14A0.9300
C1—C61.414 (3)C15—C201.406 (3)
C2—C31.388 (4)C15—C161.408 (3)
C2—H2C0.9300C16—C171.397 (3)
C3—C41.387 (4)C17—C181.399 (3)
C3—H3B0.9300C17—H17A0.9300
C4—C51.393 (3)C18—C191.391 (3)
C4—H4A0.9300C19—C201.391 (3)
C5—C61.410 (3)C19—H19A0.9300
C5—H5A0.9300O1—H1A0.83 (3)
C6—C71.482 (3)O2—H2A0.80 (3)
C8—C91.480 (3)
C8—N1—N2109.60 (16)C11—C10—C9119.3 (2)
C8—N1—C15133.55 (17)C12—C11—C10121.2 (3)
N2—N1—C15116.84 (15)C12—C11—H11A119.4
C7—N2—N1103.59 (15)C10—C11—H11A119.4
C8—N3—C7104.99 (16)C11—C12—C13120.6 (3)
O2—C1—C2117.2 (2)C11—C12—H12A119.7
O2—C1—C6122.65 (19)C13—C12—H12A119.7
C2—C1—C6120.2 (2)C14—C13—C12118.9 (3)
C3—C2—C1120.3 (2)C14—C13—H13A120.5
C3—C2—H2C119.9C12—C13—H13A120.5
C1—C2—H2C119.9C13—C14—C9121.8 (3)
C4—C3—C2120.6 (2)C13—C14—H14A119.1
C4—C3—H3B119.7C9—C14—H14A119.1
C2—C3—H3B119.7C20—C15—C16118.40 (19)
C3—C4—C5119.7 (2)C20—C15—N1120.51 (19)
C3—C4—H4A120.2C16—C15—N1121.03 (19)
C5—C4—H4A120.2C17—C16—C15121.3 (2)
C4—C5—C6121.0 (2)C17—C16—Cl2119.75 (17)
C4—C5—H5A119.5C15—C16—Cl2118.97 (16)
C6—C5—H5A119.5C16—C17—C18118.2 (2)
C5—C6—C1118.25 (19)C16—C17—H17A120.9
C5—C6—C7120.75 (19)C18—C17—H17A120.9
C1—C6—C7120.97 (18)C19—C18—C17122.1 (2)
N2—C7—N3113.35 (17)C19—C18—Cl3119.10 (19)
N2—C7—C6121.76 (18)C17—C18—Cl3118.77 (18)
N3—C7—C6124.89 (17)C18—C19—C20118.7 (2)
N3—C8—N1108.46 (17)C18—C19—H19A120.7
N3—C8—C9123.73 (18)C20—C19—H19A120.7
N1—C8—C9127.77 (19)C19—C20—C15121.3 (2)
C14—C9—C10118.1 (2)C19—C20—Cl1119.44 (19)
C14—C9—C8123.0 (2)C15—C20—Cl1119.25 (17)
C10—C9—C8118.8 (2)C10—O1—H1A109 (2)
O1—C10—C11117.4 (2)C1—O2—H2A110.6 (19)
O1—C10—C9123.3 (2)
C8—N1—N2—C70.1 (2)C14—C9—C10—O1177.2 (2)
C15—N1—N2—C7179.52 (17)C8—C9—C10—O14.5 (3)
O2—C1—C2—C3178.7 (2)C14—C9—C10—C112.7 (3)
C6—C1—C2—C30.9 (4)C8—C9—C10—C11175.6 (2)
C1—C2—C3—C40.8 (4)O1—C10—C11—C12179.0 (3)
C2—C3—C4—C50.2 (4)C9—C10—C11—C120.9 (4)
C3—C4—C5—C60.2 (4)C10—C11—C12—C131.9 (5)
C4—C5—C6—C10.0 (3)C11—C12—C13—C142.6 (5)
C4—C5—C6—C7177.9 (2)C12—C13—C14—C90.7 (5)
O2—C1—C6—C5179.0 (2)C10—C9—C14—C132.0 (4)
C2—C1—C6—C50.6 (3)C8—C9—C14—C13176.3 (3)
O2—C1—C6—C71.1 (3)C8—N1—C15—C20100.5 (3)
C2—C1—C6—C7178.4 (2)N2—N1—C15—C2079.1 (2)
N1—N2—C7—N30.2 (2)C8—N1—C15—C1682.6 (3)
N1—N2—C7—C6179.23 (17)N2—N1—C15—C1697.8 (2)
C8—N3—C7—N20.2 (2)C20—C15—C16—C171.3 (3)
C8—N3—C7—C6179.23 (18)N1—C15—C16—C17178.30 (19)
C5—C6—C7—N2177.3 (2)C20—C15—C16—Cl2178.83 (16)
C1—C6—C7—N20.6 (3)N1—C15—C16—Cl21.8 (3)
C5—C6—C7—N32.1 (3)C15—C16—C17—C180.7 (3)
C1—C6—C7—N3179.90 (19)Cl2—C16—C17—C18179.45 (17)
C7—N3—C8—N10.1 (2)C16—C17—C18—C190.5 (4)
C7—N3—C8—C9178.01 (19)C16—C17—C18—Cl3179.86 (17)
N2—N1—C8—N30.0 (2)C17—C18—C19—C201.0 (4)
C15—N1—C8—N3179.5 (2)Cl3—C18—C19—C20179.63 (19)
N2—N1—C8—C9177.80 (19)C18—C19—C20—C150.3 (4)
C15—N1—C8—C92.6 (4)C18—C19—C20—Cl1179.26 (19)
N3—C8—C9—C14176.2 (2)C16—C15—C20—C190.8 (3)
N1—C8—C9—C146.3 (4)N1—C15—C20—C19177.8 (2)
N3—C8—C9—C105.6 (3)C16—C15—C20—Cl1179.62 (16)
N1—C8—C9—C10172.0 (2)N1—C15—C20—Cl12.6 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N30.83 (3)1.89 (3)2.640 (3)149 (3)
O2—H2A···N20.81 (2)1.94 (2)2.648 (3)146 (3)

Experimental details

Crystal data
Chemical formulaC20H12Cl3N3O2
Mr432.68
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)14.328 (3), 12.021 (2), 12.014 (2)
β (°) 104.99 (3)
V3)1998.7 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.48
Crystal size (mm)0.20 × 0.20 × 0.18
Data collection
DiffractometerRigaku SCXmini
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.907, 0.915
No. of measured, independent and
observed [I > 2σ(I)] reflections
16254, 3501, 3052
Rint0.047
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.104, 1.11
No. of reflections3501
No. of parameters261
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.36, 0.35

Computer programs: CrystalClear (Rigaku, 2005), CrystalClear (Rigaku, 2005, SHELXTL/PC (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N30.83 (3)1.89 (3)2.640 (3)149 (3)
O2—H2A···N20.81 (2)1.94 (2)2.648 (3)146 (3)
 

References

First citationNisbet-Brown, E., Olivieri, N. F., Giardina, P. J., Grady, R. W., Neufeld, E. J., Sechaud, R., Krebs-Brown, A. J., Anderson, J. R., Alberti, D., Sizer, K. C. & Nathan, D. G. (2003). Lancet, 361, 1597–1602.  Web of Science CrossRef PubMed CAS Google Scholar
First citationRigaku (2005). CrystalClear. Version 1.4.0. 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 citationSteinhauser, S., Heinz, U., Bartholomä, M., Weyhermüller, T., Nick, H. & Hegetschweiler, K. (2004). Eur. J. Inorg. Chem. pp. 4177–4192.  Web of Science CSD CrossRef Google Scholar

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