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Acta Cryst. (2009). E65, m1443    [ doi:10.1107/S1600536809043578 ]

Bis(5-amino-2-chlorobenzoato-[kappa]O)triphenylantimony(V)

L. Wen, H. Yin and C. Wang

Abstract top

In the title compound, [Sb(C6H5)3(C7H5ClNO2)2], the Sb center has a distorted trigonal-bipyramidal geometry, with the O atoms of two carboxylate groups in axial positions and the C atoms of the phenyl groups in equatorial positions. Intramolecular C-H...O interactions occur. The molecules are connected by intermolecular N-H...O, N-H...N and C-H...O hydrogen-bonding interactions and C-H...[pi] stacking interactions, forming a three-dimensional supramolecular framework

Comment top

Recently, the chemistry of antimony complexes derived from carboxylates has become an active area of research due to the biological perspective and their versatile bonding modes, the striking structural possibilities ranging from discrete monomeric structures to supramolecular assemblies (Yin et al. 2009). As a part of our ongoing investigations in ths field we have synthesized the title compound and determined its crystal structure. As is shown in Fig. 1, the central antimony atom is five-coordinated with a slightly distorted trigonal bipyramidal geometry. Around the central Sb1 atom, C15, C21 and C27 occupy the equatorial plane, while O1 and O3 lie in axial sites. The Sb—O bond distances (Sb1—O1 = 2.137 (3) Å; Sb1—O3 = 2.125 (3) Å) (Table 1) are comparable to those found in organoantimony arylhydroxmates (Wang et al. 2005). The Sb—C bond distances (Sb1—C15 = 2.108 (5) Å; Sb1—C21 = 2.098 (5) Å; Sb1—C27 = 2.109 (5) Å) of the compound lie within the normal range for Sb—C (phenyl) bonds (2.10–2.13 Å). The supramolecular structure of the title compound results from intermolecular C—H···O, N—H···O and N—H···N hydrogen-bonding interactions and C—H···Π stacking interactions (Fig. 2, Table 2) assembling the molecules into a three-dimensional supramolecular frameworks

Related literature top

For related structures, see: Yin et al. (2009); Wang et al. (2005).

Experimental top

The reaction was carried out under nitrogen atmosphere. 5-Amino-2-chlorobenzoic acid (1 mmol) and sodium ethoxide (1.2 mmol) were added to a stirred solution of methanol (30 ml) in a Schlenk flask and stirred for 0.5 h. Triphenylantimony dichloride (0.5 mmol) was then added to the reactor and the reaction mixture was stirred for 12 h at room temperature. The resulting clear solution was evaporated under vacuum. The product was crystallized from a mixture of ether/n-hexane (1:1) to yield colourless blocks of the title compound (yield 80%). Anal. Calcd (%) for C32H25Cl2N2O4Sb (Mr = 694.19): C, 55.37; H, 3.63; Cl, 10.21; N, 4.04. Found (%): C, 55.31; H, 3.76; Cl, 10.31; N, 4.15.

Refinement top

The N-bound H atoms were located in a difference Fourier map. In the refinement process the N-H bond lengths were restrained to 0.85 (2) Å and isotropic displacement parameters of these H atoms were freely refined. Other H atoms were positioned geometrically, with C—H = 0.93 Å and refined with a riding model; Uiso(H) = 1.2 Ueq (C).

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); 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 compound, showing 50% probability displacement ellipsoids. H atoms have been omitted for clarity.
[Figure 2] Fig. 2. View of the three-dimensional supramolecular network structure in the title compound.
Bis(5-amino-2-chlorobenzoato-κO)triphenylantimony(V) top
Crystal data top
[Sb(C6H5)3(C7H5ClNO2)2]F(000) = 2784
Mr = 694.19Dx = 1.503 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3588 reflections
a = 30.683 (3) Åθ = 2.4–23.7°
b = 9.0128 (12) ŵ = 1.11 mm−1
c = 23.096 (3) ÅT = 298 K
β = 106.161 (2)°Block, colourless
V = 6134.6 (12) Å30.35 × 0.33 × 0.17 mm
Z = 8
Data collection top
Siemens SMART CCD area-detector
diffractometer		5409 independent reflections
Radiation source: fine-focus sealed tube3450 reflections with I > 2σ(I)
graphiteRint = 0.046
φ and ω scansθmax = 25.0°, θmin = 1.4°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −25→36
Tmin = 0.697, Tmax = 0.833k = −10→10
15481 measured reflectionsl = −27→22
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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.087H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0252P)2 + 12.9995P]
where P = (Fo2 + 2Fc2)/3
5409 reflections(Δ/σ)max < 0.001
386 parametersΔρmax = 0.86 e Å−3
4 restraintsΔρmin = −0.49 e Å−3
Crystal data top
[Sb(C6H5)3(C7H5ClNO2)2]V = 6134.6 (12) Å3
Mr = 694.19Z = 8
Monoclinic, C2/cMo Kα radiation
a = 30.683 (3) ŵ = 1.11 mm−1
b = 9.0128 (12) ÅT = 298 K
c = 23.096 (3) Å0.35 × 0.33 × 0.17 mm
β = 106.161 (2)°
Data collection top
Siemens SMART CCD area-detector
diffractometer		5409 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		3450 reflections with I > 2σ(I)
Tmin = 0.697, Tmax = 0.833Rint = 0.046
15481 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.038 w = 1/[σ2(Fo2) + (0.0252P)2 + 12.9995P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.087Δρmax = 0.86 e Å−3
S = 1.04Δρmin = −0.49 e Å−3
5409 reflectionsAbsolute structure: ?
386 parametersFlack parameter: ?
4 restraintsRogers parameter: ?
H atoms treated by a mixture of independent and constrained refinement
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Sb10.133450 (10)0.75719 (4)0.387976 (14)0.03529 (11)
Cl10.19341 (5)0.92982 (17)0.61118 (7)0.0683 (4)
Cl20.17565 (5)0.4095 (2)0.25676 (8)0.0998 (7)
N10.02031 (18)1.2629 (6)0.5343 (2)0.0590 (12)
N2−0.00974 (17)0.4432 (6)0.0918 (2)0.0567 (13)
O10.14690 (11)0.8704 (3)0.47239 (14)0.0427 (8)
O20.08342 (11)0.7652 (4)0.48081 (14)0.0478 (8)
O30.12400 (10)0.6602 (3)0.30150 (13)0.0411 (8)
O40.06817 (10)0.5306 (4)0.32076 (15)0.0445 (9)
C10.11308 (17)0.8607 (5)0.4962 (2)0.0390 (12)
C20.10837 (16)0.9804 (5)0.5384 (2)0.0382 (12)
C30.14220 (16)1.0253 (5)0.5887 (2)0.0432 (13)
C40.13472 (19)1.1428 (6)0.6237 (2)0.0531 (14)
H40.15701.16960.65850.064*
C50.09432 (19)1.2197 (6)0.6068 (2)0.0571 (15)
H50.08981.29970.62990.069*
C60.06032 (18)1.1792 (6)0.5558 (2)0.0469 (13)
C70.06747 (17)1.0588 (5)0.5228 (2)0.0426 (12)
H70.04451.02900.48930.051*
C80.09252 (16)0.5591 (5)0.2885 (2)0.0360 (11)
C90.08637 (16)0.4847 (5)0.2287 (2)0.0367 (11)
C100.12097 (16)0.4236 (6)0.2091 (2)0.0524 (14)
C110.11202 (19)0.3647 (6)0.1518 (3)0.0648 (17)
H110.13530.32130.13920.078*
C120.06878 (19)0.3698 (6)0.1131 (2)0.0560 (15)
H120.06350.33310.07410.067*
C130.03327 (16)0.4285 (5)0.1315 (2)0.0388 (12)
C140.04275 (16)0.4845 (5)0.1899 (2)0.0391 (12)
H140.01910.52310.20320.047*
C150.07540 (17)0.8918 (5)0.3575 (2)0.0408 (12)
C160.0831 (2)1.0412 (6)0.3515 (3)0.0618 (16)
H160.11261.07680.35950.074*
C170.0468 (3)1.1380 (7)0.3337 (3)0.084 (2)
H170.05181.23840.32860.100*
C180.0039 (3)1.0854 (8)0.3236 (3)0.080 (2)
H18−0.02031.15140.31290.095*
C19−0.00454 (19)0.9387 (7)0.3289 (3)0.0665 (17)
H19−0.03420.90470.32120.080*
C200.03162 (18)0.8400 (6)0.3460 (2)0.0526 (14)
H200.02620.73940.34970.063*
C210.18995 (16)0.8670 (5)0.3742 (2)0.0413 (12)
C220.22768 (18)0.8915 (6)0.4213 (3)0.0553 (15)
H220.22830.85950.45980.066*
C230.26495 (19)0.9639 (7)0.4118 (3)0.0706 (18)
H230.29080.97840.44370.085*
C240.2638 (2)1.0132 (8)0.3563 (4)0.085 (2)
H240.28871.06280.35030.102*
C250.2264 (2)0.9912 (8)0.3089 (3)0.098 (3)
H250.22591.02550.27080.117*
C260.18914 (19)0.9175 (7)0.3177 (3)0.0725 (19)
H260.16360.90220.28540.087*
C270.15298 (16)0.5477 (5)0.4274 (2)0.0375 (12)
C280.18933 (18)0.4839 (6)0.4126 (2)0.0545 (15)
H280.20480.53630.38980.065*
C290.2027 (2)0.3410 (7)0.4322 (3)0.0680 (17)
H290.22740.29800.42280.082*
C300.1797 (2)0.2636 (6)0.4651 (3)0.0632 (16)
H300.18860.16760.47790.076*
C310.14364 (19)0.3273 (6)0.4793 (3)0.0584 (16)
H310.12800.27380.50150.070*
C320.12994 (16)0.4711 (5)0.4609 (2)0.0447 (13)
H320.10560.51440.47130.054*
H1A−0.0042 (13)1.213 (6)0.521 (3)0.09 (3)*
H2A−0.0141 (17)0.386 (5)0.0615 (16)0.061 (19)*
H1B0.0182 (19)1.324 (5)0.5623 (19)0.08 (2)*
H2B−0.0315 (12)0.450 (6)0.108 (2)0.057 (19)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Sb10.03935 (18)0.03370 (18)0.03511 (18)−0.00248 (17)0.01417 (13)−0.00089 (18)
Cl10.0535 (9)0.0761 (11)0.0696 (11)0.0103 (8)0.0079 (7)−0.0040 (8)
Cl20.0513 (10)0.1624 (19)0.0777 (13)0.0366 (11)0.0047 (8)−0.0392 (12)
N10.059 (3)0.057 (3)0.064 (3)0.010 (3)0.023 (3)0.000 (3)
N20.049 (3)0.077 (4)0.043 (3)−0.002 (3)0.010 (3)−0.014 (3)
O10.047 (2)0.047 (2)0.038 (2)0.0001 (16)0.0193 (17)−0.0075 (16)
O20.058 (2)0.039 (2)0.050 (2)−0.0073 (18)0.0201 (17)−0.0049 (18)
O30.049 (2)0.0379 (19)0.038 (2)−0.0100 (16)0.0161 (16)−0.0050 (16)
O40.042 (2)0.055 (2)0.040 (2)−0.0035 (17)0.0166 (17)−0.0031 (17)
C10.050 (3)0.031 (3)0.038 (3)0.003 (2)0.014 (3)0.001 (2)
C20.049 (3)0.035 (3)0.036 (3)−0.005 (2)0.021 (2)0.001 (2)
C30.047 (3)0.045 (3)0.039 (3)0.002 (2)0.014 (3)0.003 (2)
C40.063 (4)0.055 (4)0.041 (3)−0.003 (3)0.014 (3)−0.007 (3)
C50.066 (4)0.061 (4)0.050 (4)0.000 (3)0.025 (3)−0.013 (3)
C60.050 (3)0.042 (3)0.054 (4)0.000 (3)0.023 (3)0.004 (3)
C70.054 (3)0.040 (3)0.034 (3)−0.005 (2)0.012 (2)−0.001 (2)
C80.038 (3)0.033 (3)0.038 (3)0.004 (2)0.012 (2)0.003 (2)
C90.039 (3)0.036 (3)0.039 (3)0.000 (2)0.018 (2)0.001 (2)
C100.041 (3)0.066 (4)0.052 (4)0.009 (3)0.014 (3)−0.012 (3)
C110.060 (4)0.077 (4)0.064 (4)0.015 (3)0.027 (3)−0.027 (3)
C120.064 (4)0.059 (4)0.045 (4)−0.003 (3)0.016 (3)−0.021 (3)
C130.046 (3)0.037 (3)0.037 (3)−0.005 (2)0.017 (3)−0.006 (2)
C140.041 (3)0.036 (3)0.045 (3)−0.002 (2)0.019 (2)−0.001 (2)
C150.050 (3)0.040 (3)0.034 (3)0.002 (2)0.014 (2)0.000 (2)
C160.072 (4)0.038 (3)0.073 (5)0.002 (3)0.018 (3)0.006 (3)
C170.118 (6)0.037 (4)0.092 (6)0.025 (4)0.024 (5)0.005 (3)
C180.092 (5)0.072 (5)0.074 (5)0.044 (4)0.023 (4)0.006 (4)
C190.056 (4)0.070 (4)0.077 (5)0.019 (3)0.023 (3)0.008 (4)
C200.052 (4)0.046 (3)0.061 (4)0.011 (3)0.018 (3)0.005 (3)
C210.045 (3)0.037 (3)0.047 (3)−0.006 (2)0.021 (3)−0.006 (2)
C220.052 (4)0.061 (4)0.053 (4)−0.010 (3)0.013 (3)−0.004 (3)
C230.045 (4)0.085 (5)0.078 (5)−0.019 (3)0.010 (3)−0.020 (4)
C240.073 (5)0.090 (5)0.105 (6)−0.037 (4)0.044 (5)−0.015 (5)
C250.099 (6)0.126 (7)0.080 (6)−0.046 (5)0.043 (5)0.012 (5)
C260.063 (4)0.101 (5)0.057 (4)−0.040 (4)0.022 (3)0.006 (4)
C270.042 (3)0.033 (3)0.034 (3)0.002 (2)0.004 (2)0.001 (2)
C280.060 (4)0.050 (3)0.060 (4)0.012 (3)0.027 (3)0.005 (3)
C290.066 (4)0.064 (4)0.073 (5)0.027 (3)0.018 (3)0.003 (4)
C300.076 (4)0.037 (3)0.068 (4)0.007 (3)0.005 (3)0.008 (3)
C310.057 (4)0.044 (3)0.070 (4)−0.009 (3)0.010 (3)0.011 (3)
C320.044 (3)0.041 (3)0.049 (3)−0.003 (2)0.011 (3)0.006 (3)
Geometric parameters (Å, °) top
Sb1—C212.098 (5)C13—C141.392 (6)
Sb1—C152.108 (5)C14—H140.9300
Sb1—C272.109 (5)C15—C201.376 (6)
Sb1—O32.125 (3)C15—C161.381 (6)
Sb1—O12.137 (3)C16—C171.383 (7)
Cl1—C31.739 (5)C16—H160.9300
Cl2—C101.736 (5)C17—C181.357 (8)
N1—C61.408 (7)C17—H170.9300
N1—H1A0.86 (2)C18—C191.360 (8)
N1—H1B0.865 (19)C18—H180.9300
N2—C131.388 (6)C19—C201.391 (7)
N2—H2A0.847 (19)C19—H190.9300
N2—H2B0.847 (19)C20—H200.9300
O1—C11.305 (5)C21—C221.369 (6)
O2—C11.231 (5)C21—C261.375 (7)
O3—C81.301 (5)C22—C231.386 (7)
O4—C81.220 (5)C22—H220.9300
C1—C21.488 (6)C23—C241.348 (8)
C2—C31.385 (6)C23—H230.9300
C2—C71.397 (6)C24—C251.361 (9)
C3—C41.390 (7)C24—H240.9300
C4—C51.378 (7)C25—C261.385 (7)
C4—H40.9300C25—H250.9300
C5—C61.387 (7)C26—H260.9300
C5—H50.9300C27—C321.372 (6)
C6—C71.378 (6)C27—C281.379 (6)
C7—H70.9300C28—C291.388 (7)
C8—C91.499 (6)C28—H280.9300
C9—C101.379 (6)C29—C301.364 (8)
C9—C141.388 (6)C29—H290.9300
C10—C111.381 (7)C30—C311.366 (7)
C11—C121.378 (7)C30—H300.9300
C11—H110.9300C31—C321.391 (7)
C12—C131.380 (6)C31—H310.9300
C12—H120.9300C32—H320.9300
C21—Sb1—C15109.59 (19)C9—C14—C13122.0 (5)
C21—Sb1—C27109.92 (19)C9—C14—H14119.0
C15—Sb1—C27140.49 (19)C13—C14—H14119.0
C21—Sb1—O387.33 (16)C20—C15—C16119.7 (5)
C15—Sb1—O392.36 (15)C20—C15—Sb1123.9 (4)
C27—Sb1—O389.15 (15)C16—C15—Sb1116.3 (4)
C21—Sb1—O187.45 (16)C15—C16—C17120.0 (6)
C15—Sb1—O187.74 (15)C15—C16—H16120.0
C27—Sb1—O194.27 (15)C17—C16—H16120.0
O3—Sb1—O1174.49 (12)C18—C17—C16119.5 (6)
C6—N1—H1A116 (4)C18—C17—H17120.3
C6—N1—H1B108 (4)C16—C17—H17120.3
H1A—N1—H1B112 (6)C17—C18—C19121.6 (6)
C13—N2—H2A113 (4)C17—C18—H18119.2
C13—N2—H2B116 (4)C19—C18—H18119.2
H2A—N2—H2B116 (5)C18—C19—C20119.4 (6)
C1—O1—Sb1112.2 (3)C18—C19—H19120.3
C8—O3—Sb1113.8 (3)C20—C19—H19120.3
O2—C1—O1122.4 (4)C15—C20—C19119.8 (5)
O2—C1—C2119.8 (5)C15—C20—H20120.1
O1—C1—C2117.5 (4)C19—C20—H20120.1
C3—C2—C7118.5 (4)C22—C21—C26119.3 (5)
C3—C2—C1125.1 (4)C22—C21—Sb1120.5 (4)
C7—C2—C1116.2 (4)C26—C21—Sb1120.2 (4)
C2—C3—C4120.3 (5)C21—C22—C23120.1 (5)
C2—C3—Cl1120.6 (4)C21—C22—H22119.9
C4—C3—Cl1119.0 (4)C23—C22—H22119.9
C5—C4—C3119.9 (5)C24—C23—C22120.1 (6)
C5—C4—H4120.0C24—C23—H23120.0
C3—C4—H4120.0C22—C23—H23120.0
C4—C5—C6120.9 (5)C23—C24—C25120.6 (6)
C4—C5—H5119.6C23—C24—H24119.7
C6—C5—H5119.6C25—C24—H24119.7
C7—C6—C5118.6 (5)C24—C25—C26119.8 (7)
C7—C6—N1118.9 (5)C24—C25—H25120.1
C5—C6—N1122.3 (5)C26—C25—H25120.1
C6—C7—C2121.7 (5)C21—C26—C25120.0 (6)
C6—C7—H7119.1C21—C26—H26120.0
C2—C7—H7119.1C25—C26—H26120.0
O4—C8—O3123.2 (5)C32—C27—C28120.6 (5)
O4—C8—C9121.8 (4)C32—C27—Sb1124.4 (4)
O3—C8—C9114.9 (4)C28—C27—Sb1114.8 (4)
C10—C9—C14118.6 (5)C27—C28—C29119.5 (5)
C10—C9—C8124.7 (4)C27—C28—H28120.2
C14—C9—C8116.6 (4)C29—C28—H28120.2
C9—C10—C11120.1 (5)C30—C29—C28120.3 (6)
C9—C10—Cl2121.1 (4)C30—C29—H29119.9
C11—C10—Cl2118.6 (4)C28—C29—H29119.9
C12—C11—C10120.5 (5)C29—C30—C31119.8 (5)
C12—C11—H11119.8C29—C30—H30120.1
C10—C11—H11119.8C31—C30—H30120.1
C11—C12—C13120.9 (5)C30—C31—C32121.0 (6)
C11—C12—H12119.6C30—C31—H31119.5
C13—C12—H12119.6C32—C31—H31119.5
C12—C13—N2121.3 (5)C27—C32—C31118.7 (5)
C12—C13—C14117.8 (5)C27—C32—H32120.6
N2—C13—C14120.6 (5)C31—C32—H32120.6
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C32—H32···O20.932.393.105 (6)134
C20—H20···O40.932.473.120 (6)127
N1—H1B···N2i0.87 (2)2.43 (3)3.211 (8)150 (5)
N1—H1A···O2ii0.86 (2)2.43 (5)3.114 (6)137 (5)
N2—H2A···N1iii0.85 (2)2.44 (2)3.272 (7)169 (5)
N2—H2B···O4iv0.85 (2)2.36 (3)3.151 (6)156 (5)
C14—H14···O4iv0.932.583.369 (6)143
C12—H12···O2v0.932.563.433 (6)157
C23—H23···Cg1vi0.932.723.567 (7)151
Symmetry codes: (i) x, −y+2, z+1/2; (ii) −x, −y+2, −z+1; (iii) −x, y−1, −z+1/2; (iv) −x, y, −z+1/2; (v) x, −y+1, z−1/2; (vi) −x+1/2, −y+3/2, −z+1.
Table 1
Selected geometric parameters (Å, °) top
Sb1—C212.098 (5)Sb1—O32.125 (3)
Sb1—C152.108 (5)Sb1—O12.137 (3)
Sb1—C272.109 (5)
C21—Sb1—C15109.59 (19)C27—Sb1—O389.15 (15)
C21—Sb1—C27109.92 (19)C21—Sb1—O187.45 (16)
C15—Sb1—C27140.49 (19)C15—Sb1—O187.74 (15)
C21—Sb1—O387.33 (16)C27—Sb1—O194.27 (15)
C15—Sb1—O392.36 (15)O3—Sb1—O1174.49 (12)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C32—H32···O20.932.393.105 (6)134
C20—H20···O40.932.473.120 (6)127
N1—H1B···N2i0.87 (2)2.43 (3)3.211 (8)150 (5)
N1—H1A···O2ii0.86 (2)2.43 (5)3.114 (6)137 (5)
N2—H2A···N1iii0.85 (2)2.44 (2)3.272 (7)169 (5)
N2—H2B···O4iv0.85 (2)2.36 (3)3.151 (6)156 (5)
C14—H14···O4iv0.932.583.369 (6)143
C12—H12···O2v0.932.563.433 (6)157
C23—H23···Cg1vi0.932.723.567 (7)151
Symmetry codes: (i) x, −y+2, z+1/2; (ii) −x, −y+2, −z+1; (iii) −x, y−1, −z+1/2; (iv) −x, y, −z+1/2; (v) x, −y+1, z−1/2; (vi) −x+1/2, −y+3/2, −z+1.
Acknowledgements top

We acknowledge the National Natural Science Foundation of China (20771053) and the Natural Science Foundation of Shandong Province (Y2008B48) for financial support.

references
References top

Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.

Wang, G. C., Lu, Y. N., Xiao, J., Yu, L., Song, H. B., Li, J. S., Cui, J. R., Wang, R. Q. & Ran, F. X. (2005). J. Organomet. Chem. 690, 151–156.

Yin, H. D., Wen, L. Y., Cui, J. C. & Li, W. K. (2009). Polyhedron, 28, 2919–2926.