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

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Bis(5-bromo­pyridine-2-carboxyl­ato-κO)tri­phenyl­anti­mony(V)

aCollege of Chemistry and Chemical Engineering, Liaocheng University, Shandong 252059, People's Republic of China
*Correspondence e-mail: handongyin@163.com

(Received 20 September 2008; accepted 16 October 2008; online 8 November 2008)

In the title compound, [Sb(C6H5)3(C6H3BrNO2)2], the Sb center has a distorted trigonal–bipyramidal geometry, with two carboxyl­ate O atoms of two 5-bromo­pyridine-2-carboxyl­ate ligands in equatorial positions and three phenyl ligands in axial positions. The crystal structure is stabilized by C—H⋯Br hydrogen bonds and inter­molecular C—Br⋯π inter­actions [C⋯π = 3.57 (1) Å].

Related literature

For the synthesis and structures of related triphenyl­anti­mony compounds, see: Yin et al. (2008[Yin, H. D., Quan, L. & Li, L. W. (2008). Inorg. Chem. Commun. 11, 1122-1125.]); Chaudhari et al. (2007[Chaudhari, K. R., Jain, V. K., Sagoria, V. S. & Tiekink, E. R. T. (2007). J. Organomet. Chem. 692, 4928-4932.]); Mahon et al. (1998[Mahon, M. F., Molloy, K. C., Omotowa, B. A. & Mesubi, M. A. (1998). J. Organomet. Chem. 560, 95-101.]); Quan et al. (2008[Quan, L., Yin, H. & Wang, D. (2008). Acta Cryst. E64, m1302.]).

[Scheme 1]

Experimental

Crystal data
  • [Sb(C6H5)3(C6H3BrNO2)2]

  • Mr = 755.06

  • Orthorhombic, F d d 2

  • a = 20.597 (2) Å

  • b = 13.057 (1) Å

  • c = 20.541 (2) Å

  • V = 5524.2 (9) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 3.93 mm−1

  • T = 298 (2) K

  • 0.43 × 0.37 × 0.20 mm

Data collection
  • Siemens SMART diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.204, Tmax = 0.460

  • 5869 measured reflections

  • 2564 independent reflections

  • 1861 reflections with I > 2σ(I)

  • Rint = 0.081

Refinement
  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.166

  • S = 1.01

  • 2564 reflections

  • 178 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 1.02 e Å−3

  • Δρmin = −0.86 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1172 Friedel pairs

  • Flack parameter: 0.02 (3)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10⋯Bri 0.93 2.90 3.69 (2) 144
Symmetry code: (i) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z].

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 1998[Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

The triphenylantimony compound containing the heterocyclic pyridine carboxylate skeleton show some potential biological activity (Yin et al., 2008) and we have synthesized the title compound (I) and report its crystal structure here.

As shown in Fig. 1, the Sb atom is five-coordinated by the three phenyl C atoms and the two carboxylate O atoms. The average distance of Sb—C (2.10 Å) in the (I) is shorter than the average distance of S—C (2.225 Å; Mahon et al., 1998). The average distance of Sb—O (2.146 Å) in the (I) is equal to the average distance of Sb—O (2.145 Å; Chaudhari et al., 2007). The crystal structure is stabilized by intermolecular C—H···Br hydrogen bonds (Fig. 2 and Table 1; symmetry code as in Fig. 2). In addition, the crystal structure exhibits C—Br···π interactions, with a C5—Br···Cgii separation of 3.57 (1) Å (Fig. 2; Cg is the centroid of the C7-C12 benzene ring, symmetry code as in Fig. 2).

Related literature top

For the synthesis and structures of related triphenylantimony compounds, see: Yin et al. (2008); Chaudhari et al. (2007); Mahon et al. (1998); Quan et al. (2008)

Experimental top

5-bromopyridine-2-carboxylic acid (0.061 g, 0.3 mmol) and sodium methoxide (0.6 ml, 0.3 mmol) was added to a stirring solution containing triphenylantimonydichloride (0.064 g, 0.15 mmol) in toluene (25 ml). After refluxing for 8 h, the colorless solution was obtained and then filtered. The solvent was gradually removed by evaporation under vacuum until the white solid is obtained. The solid was recrystallized from petroleum ether/dichoromethane (1:1) to give colorless crystals.

Refinement top

All H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 Å, Uiso(H) = 1.2Ueq(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: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids drawn at the 30% probability level. [Symmetry code: (i) -x+1, -y+1, z.]
[Figure 2] Fig. 2. C—H···Br and C—Br···π interactions (dotted lines) in the title compound. Cg denotes the ring centroid. [Symmetry code: (i) -x+1/2, -y+1/2, z; (ii) x, y-1, z; (iii)-x+1/2, -y+1/2, z; (iv) -x+1, -y+1, z; (v) -x+1, -y+2, z; (vi) x+1/2, y+1/2, z.]
Bis(5-bromopyridine-2-carboxylato-κO)triphenylantimony(V) top
Crystal data top
[Sb(C6H5)3(C6H3BrNO2)2]F(000) = 2944
Mr = 755.06Dx = 1.816 Mg m3
Orthorhombic, Fdd2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: f 2 -2dCell parameters from 2025 reflections
a = 20.597 (2) Åθ = 2.8–24.1°
b = 13.057 (1) ŵ = 3.93 mm1
c = 20.541 (2) ÅT = 298 K
V = 5524.2 (9) Å3Block, colorless
Z = 80.43 × 0.37 × 0.20 mm
Data collection top
Siemens SMART
diffractometer
2564 independent reflections
Radiation source: fine-focus sealed tube1861 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.081
Detector resolution: 20.0 pixels mm-1θmax = 26.0°, θmin = 2.1°
ϕ and ω scansh = 2325
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1612
Tmin = 0.204, Tmax = 0.460l = 2425
5869 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.060H-atom parameters constrained
wR(F2) = 0.166 w = 1/[σ2(Fo2) + (0.0963P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
2564 reflectionsΔρmax = 1.02 e Å3
178 parametersΔρmin = 0.86 e Å3
1 restraintAbsolute structure: Flack (1983), 1172 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.02 (3)
Crystal data top
[Sb(C6H5)3(C6H3BrNO2)2]V = 5524.2 (9) Å3
Mr = 755.06Z = 8
Orthorhombic, Fdd2Mo Kα radiation
a = 20.597 (2) ŵ = 3.93 mm1
b = 13.057 (1) ÅT = 298 K
c = 20.541 (2) Å0.43 × 0.37 × 0.20 mm
Data collection top
Siemens SMART
diffractometer
2564 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1861 reflections with I > 2σ(I)
Tmin = 0.204, Tmax = 0.460Rint = 0.081
5869 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.060H-atom parameters constrained
wR(F2) = 0.166Δρmax = 1.02 e Å3
S = 1.01Δρmin = 0.86 e Å3
2564 reflectionsAbsolute structure: Flack (1983), 1172 Friedel pairs
178 parametersAbsolute structure parameter: 0.02 (3)
1 restraint
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
Sb0.50000.50000.64254 (4)0.0395 (3)
Br0.38657 (9)0.14610 (10)0.69850 (11)0.1021 (8)
N0.4328 (6)0.1462 (8)0.6388 (6)0.074 (3)
O10.4633 (4)0.3464 (5)0.6376 (4)0.0449 (17)
O20.4672 (5)0.3511 (7)0.7460 (5)0.064 (2)
C10.4568 (5)0.3068 (9)0.6937 (7)0.049 (3)
C20.4353 (5)0.1947 (9)0.6944 (7)0.052 (3)
C30.4223 (7)0.1484 (13)0.7532 (7)0.065 (4)
H30.42570.18600.79160.078*
C40.4047 (7)0.0490 (12)0.7557 (8)0.069 (4)
H40.39320.01780.79470.083*
C50.4046 (7)0.0025 (8)0.6998 (8)0.064 (4)
C60.4174 (9)0.0468 (10)0.6421 (10)0.084 (5)
H60.41530.00940.60360.101*
C70.4109 (5)0.5538 (8)0.6790 (6)0.044 (3)
C80.3959 (7)0.5504 (11)0.7467 (7)0.065 (3)
H80.42560.52600.77700.078*
C90.3346 (8)0.5853 (12)0.7657 (9)0.069 (5)
H90.32350.58540.80960.083*
C100.2904 (7)0.6196 (10)0.7200 (10)0.071 (4)
H100.24950.64120.73350.085*
C110.3054 (7)0.6225 (11)0.6559 (9)0.074 (4)
H110.27530.64560.62550.089*
C120.3667 (6)0.5902 (9)0.6362 (7)0.058 (3)
H120.37760.59380.59230.070*
C130.50000.50000.5399 (8)0.043 (4)
C140.5053 (6)0.4088 (10)0.5057 (6)0.058 (3)
H140.50820.34670.52770.070*
C150.5062 (7)0.4116 (12)0.4393 (6)0.068 (4)
H150.51120.35080.41620.082*
C160.50000.50000.4066 (10)0.074 (6)
H160.50000.50000.36130.089*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Sb0.0407 (5)0.0310 (4)0.0468 (5)0.0008 (5)0.0000.000
Br0.1069 (13)0.0400 (8)0.159 (2)0.0140 (8)0.0465 (13)0.0023 (10)
N0.118 (10)0.045 (6)0.058 (7)0.023 (6)0.010 (8)0.004 (6)
O10.053 (4)0.029 (4)0.052 (5)0.004 (3)0.001 (4)0.002 (4)
O20.084 (6)0.047 (5)0.060 (5)0.011 (5)0.010 (5)0.005 (4)
C10.046 (6)0.038 (6)0.064 (8)0.001 (5)0.004 (6)0.004 (6)
C20.050 (7)0.043 (6)0.064 (8)0.000 (5)0.010 (7)0.005 (6)
C30.078 (10)0.060 (9)0.057 (9)0.007 (7)0.012 (8)0.005 (7)
C40.070 (9)0.052 (8)0.086 (11)0.009 (7)0.001 (8)0.017 (8)
C50.069 (9)0.023 (6)0.101 (12)0.005 (5)0.014 (8)0.003 (8)
C60.123 (13)0.041 (7)0.089 (10)0.010 (8)0.028 (12)0.007 (9)
C70.039 (6)0.029 (5)0.064 (8)0.004 (4)0.004 (6)0.004 (5)
C80.075 (9)0.067 (9)0.053 (8)0.009 (8)0.005 (7)0.009 (7)
C90.078 (10)0.054 (8)0.075 (10)0.010 (8)0.046 (9)0.017 (7)
C100.053 (8)0.049 (8)0.111 (14)0.002 (6)0.026 (9)0.005 (8)
C110.052 (8)0.066 (9)0.105 (14)0.008 (6)0.002 (9)0.004 (8)
C120.056 (7)0.052 (7)0.068 (8)0.005 (5)0.007 (7)0.001 (6)
C130.052 (9)0.022 (7)0.056 (9)0.009 (7)0.0000.000
C140.068 (8)0.050 (7)0.057 (8)0.009 (6)0.006 (7)0.003 (6)
C150.089 (10)0.067 (9)0.049 (7)0.022 (7)0.007 (8)0.014 (6)
C160.085 (14)0.091 (16)0.045 (10)0.019 (12)0.0000.000
Geometric parameters (Å, º) top
Sb—C72.103 (11)C7—C81.425 (19)
Sb—C7i2.103 (11)C8—C91.40 (2)
Sb—C132.108 (17)C8—H80.9300
Sb—O1i2.146 (7)C9—C101.38 (2)
Sb—O12.146 (7)C9—H90.9300
Br—C51.911 (10)C10—C111.35 (2)
N—C21.309 (16)C10—H100.9300
N—C61.337 (17)C11—C121.39 (2)
O1—C11.270 (16)C11—H110.9300
O2—C11.238 (16)C12—H120.9300
C1—C21.529 (17)C13—C14i1.387 (16)
C2—C31.377 (19)C13—C141.387 (16)
C3—C41.35 (2)C14—C151.364 (19)
C3—H30.9300C14—H140.9300
C4—C51.33 (2)C15—C161.342 (18)
C4—H40.9300C15—H150.9300
C5—C61.37 (2)C16—C15i1.342 (18)
C6—H60.9300C16—H160.9300
C7—C121.352 (17)
C7—Sb—C7i138.2 (7)C12—C7—C8120.0 (12)
C7—Sb—C13110.9 (3)C12—C7—Sb118.2 (10)
C7i—Sb—C13110.9 (3)C8—C7—Sb121.8 (10)
C7—Sb—O1i90.7 (3)C9—C8—C7117.3 (15)
C7i—Sb—O1i91.2 (4)C9—C8—H8121.4
C13—Sb—O1i87.3 (2)C7—C8—H8121.4
C7—Sb—O191.2 (4)C10—C9—C8120.7 (14)
C7i—Sb—O190.7 (3)C10—C9—H9119.6
C13—Sb—O187.3 (2)C8—C9—H9119.6
O1i—Sb—O1174.6 (5)C11—C10—C9121.2 (13)
C2—N—C6115.8 (13)C11—C10—H10119.4
C1—O1—Sb112.0 (7)C9—C10—H10119.4
O2—C1—O1125.4 (11)C10—C11—C12118.8 (15)
O2—C1—C2119.3 (12)C10—C11—H11120.6
O1—C1—C2115.3 (11)C12—C11—H11120.6
N—C2—C3123.1 (12)C7—C12—C11121.9 (15)
N—C2—C1117.8 (11)C7—C12—H12119.1
C3—C2—C1119.0 (13)C11—C12—H12119.1
C4—C3—C2120.5 (14)C14i—C13—C14119.1 (16)
C4—C3—H3119.7C14i—C13—Sb120.4 (8)
C2—C3—H3119.7C14—C13—Sb120.4 (8)
C5—C4—C3117.0 (14)C15—C14—C13119.0 (13)
C5—C4—H4121.5C15—C14—H14120.5
C3—C4—H4121.5C13—C14—H14120.5
C4—C5—C6120.4 (12)C16—C15—C14121.5 (14)
C4—C5—Br120.5 (12)C16—C15—H15119.2
C6—C5—Br119.0 (11)C14—C15—H15119.2
N—C6—C5123.0 (16)C15i—C16—C15119.8 (18)
N—C6—H6118.5C15i—C16—H16120.1
C5—C6—H6118.5C15—C16—H16120.1
C7—Sb—O1—C172.0 (8)C13—Sb—C7—C8172.8 (9)
C7i—Sb—O1—C166.3 (8)O1i—Sb—C7—C899.8 (11)
C13—Sb—O1—C1177.2 (7)O1—Sb—C7—C885.2 (10)
Sb—O1—C1—O23.2 (15)C12—C7—C8—C90.4 (19)
Sb—O1—C1—C2176.0 (7)Sb—C7—C8—C9178.2 (10)
C6—N—C2—C31 (2)C7—C8—C9—C101 (2)
C6—N—C2—C1176.3 (13)C8—C9—C10—C111 (2)
O2—C1—C2—N171.3 (13)C9—C10—C11—C120 (2)
O1—C1—C2—N7.8 (15)C8—C7—C12—C111.8 (19)
O2—C1—C2—C35.8 (17)Sb—C7—C12—C11176.8 (10)
O1—C1—C2—C3175.0 (12)C10—C11—C12—C72 (2)
N—C2—C3—C41 (2)C7—Sb—C13—C14i63.8 (7)
C1—C2—C3—C4178.4 (12)C7i—Sb—C13—C14i116.2 (7)
C2—C3—C4—C54 (2)O1i—Sb—C13—C14i25.9 (7)
C3—C4—C5—C65 (2)O1—Sb—C13—C14i154.1 (7)
C3—C4—C5—Br175.5 (11)C7—Sb—C13—C14116.2 (7)
C2—N—C6—C50 (2)C7i—Sb—C13—C1463.8 (7)
C4—C5—C6—N3 (3)O1i—Sb—C13—C14154.1 (7)
Br—C5—C6—N177.5 (13)O1—Sb—C13—C1425.9 (7)
C7i—Sb—C7—C12174.2 (9)C14i—C13—C14—C151.0 (10)
C13—Sb—C7—C125.8 (9)Sb—C13—C14—C15179.0 (10)
O1i—Sb—C7—C1281.6 (9)C13—C14—C15—C162 (2)
O1—Sb—C7—C1293.3 (9)C14—C15—C16—C15i1.1 (10)
C7i—Sb—C7—C87.2 (9)
Symmetry code: (i) x+1, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10···Brii0.932.903.69 (2)144
Symmetry code: (ii) x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula[Sb(C6H5)3(C6H3BrNO2)2]
Mr755.06
Crystal system, space groupOrthorhombic, Fdd2
Temperature (K)298
a, b, c (Å)20.597 (2), 13.057 (1), 20.541 (2)
V3)5524.2 (9)
Z8
Radiation typeMo Kα
µ (mm1)3.93
Crystal size (mm)0.43 × 0.37 × 0.20
Data collection
DiffractometerSiemens SMART
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.204, 0.460
No. of measured, independent and
observed [I > 2σ(I)] reflections
5869, 2564, 1861
Rint0.081
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.166, 1.01
No. of reflections2564
No. of parameters178
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.02, 0.86
Absolute structureFlack (1983), 1172 Friedel pairs
Absolute structure parameter0.02 (3)

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10···Bri0.932.903.69 (2)143.9
Symmetry code: (i) x+1/2, y+1/2, z.
 

Acknowledgements

We acknowledge the National Natural Science Foundation of China (grant No. 20771053) and the Natural Science Foundation of Shandong Province (grant No. 2005ZX09) for financial support.

References

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