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

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ISSN: 2056-9890
Volume 64| Part 5| May 2008| Pages m637-m638

Bis(2-bromo­pyridinium) hexa­chlorido­stannate(IV)

aDepartment of Chemistry, Al al-Bayt University, Mafraq, Jordan, bFaculty of Science and IT, Al-Balqa'a Applied University, Salt, Jordan, and cDepartment of Chemistry, The University of Jordan, Amman, Jordan
*Correspondence e-mail: rohi@bau.edu.jo

(Received 6 March 2008; accepted 3 April 2008; online 10 April 2008)

The asymmetric unit of the title compound, (C5H5BrN)2[SnCl6], contains one cation and one half-anion. The [SnCl6]2− anion is located on an inversion center and forms a quasi-regular octa­hedral arrangement. Hydrogen-bonding inter­actions of two kinds, viz. N—H⋯Cl—Sn and C—H⋯Cl—Sn, along with Cl⋯Br inter­actions [3.4393 (15) Å], connect the ions in the crystal structure into two-dimensional supra­molecular arrays. These supra­molecular arrays are arranged in layers approximately parallel to (110) built up from anions inter­acting with six symmetry-related surrounding cations.

Related literature

The title salt is isomorphous with the Te-analogue, see: Fernandes et al. (2004[Fernandes, R. M. Jr, de Oliveira, G. M., Lang, E. S. & Vázquez-López, E. M. (2004). Z. Anorg. Allg. Chem. 630, 2687-2691.]). For related literature, see: Al-Far & Ali (2007[Al-Far, R. & Ali, B. F. (2007). Acta Cryst. C63, m137-m139.]); Ali, Al-Far & Al-Sou'od (2007[Ali, B. F., Al-Far, R. & Al-Sou'od, K. (2007). J. Chem. Crystallogr. 37, 265-273.]); Ali & Al-Far (2007[Ali, B. F. & Al-Far, R. (2007). Acta Cryst. E63, m892-m894.]); Ali, Al-Far & Ng (2007[Ali, B. F., Al-Far, R. & Ng, S. W. (2007). Acta Cryst. E63, m2102-m2103.]); Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]); Aruta et al. (2005[Aruta, C., Licci, F., Zappettini, A., Bolzoni, F., Rastelli, F., Ferro, P. & Besagni, T. (2005). Appl. Phys. A, 81, 963-968.]); Awwadi et al. (2007[Awwadi, F. F., Willett, R. D., Peterson, K. A. & Twamley, B. (2007). J. Phys. Chem. A, 111, 2319-2328.]); Bouacida et al. (2007[Bouacida, S., Merazig, H., Benard-Rocherulle, P. & Rizzoli, C. (2007). Acta Cryst. E63, m379-m381.]); Ellis & Macdonald (2006[Ellis, B. D. & Macdonald, C. L. B. (2006). Acta Cryst. E62, m1235-m1236.]); Hill (1998[Hill, C. L. (1998). Chem. Rev. 98, 1-2.]); Kagan et al. (1999[Kagan, C. R., Mitzi, D. B. & Dimitrakopoulos, C. D. (1999). Science, 286, 945-947.]); Knutson et al. (2005[Knutson, J. L., Martin, J. D. & Mitzi, D. B. (2005). Inorg. Chem. 44, 4699-4705.]); Li et al. (2005[Li, H.-T., Sun, R., Shi, H.-P. & Huang, S.-P. (2005). Acta Cryst. E61, m2088-m2089.]); Mitzi et al. (2001[Mitzi, D. B., Dimitrakopoulos, C. D. & Kosbar, L. L. (2001). Chem. Mater. 13, 3728-3740.]); Raptopoulou et al. (2002[Raptopoulou, C. P., Terzis, A., Mousdis, G. A. & Papavassiliou, G. C. (2002). Z. Naturforsch. Teil B, 57, 645-650.]); Willett & Haddad (2000[Willett, R. D. & Haddad, S. F. (2000). Acta Cryst. C56, e438.]).

[Scheme 1]

Experimental

Crystal data
  • (C5H5BrN)2[SnCl6]

  • Mr = 649.41

  • Monoclinic, P 21 /n

  • a = 9.0843 (14) Å

  • b = 10.6827 (9) Å

  • c = 10.6345 (17) Å

  • β = 109.843 (11)°

  • V = 970.8 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 6.25 mm−1

  • T = 296 (2) K

  • 0.20 × 0.15 × 0.10 mm

Data collection
  • Siemens P4 diffractometer

  • Absorption correction: ψ scan (XSCANS; Siemens, 1996[Siemens (1996). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]) Tmin = 0.340, Tmax = 0.535

  • 2385 measured reflections

  • 1791 independent reflections

  • 1343 reflections with I > 2σ(I)

  • Rint = 0.048

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.097

  • S = 1.05

  • 1791 reflections

  • 98 parameters

  • H-atom parameters constrained

  • Δρmax = 0.61 e Å−3

  • Δρmin = −0.73 e Å−3

Table 1
Selected geometric parameters (Å, °)

Sn1—Cl1 2.4216 (13)
Sn1—Cl2 2.4513 (14)
Sn1—Cl3 2.4212 (13)
Cl1—Sn1—Cl2 89.67 (5)
Cl3—Sn1—Cl1i 89.70 (5)
Cl3—Sn1—Cl1 90.30 (5)
Cl3—Sn1—Cl2 90.06 (6)
Cl3—Sn1—Cl2i 89.94 (6)
Symmetry code: (i) -x, -y, -z+1.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯Cl2ii 0.86 2.45 3.234 (5) 151
C3—H3⋯Cl1iii 0.93 2.77 3.646 (6) 158
C5—H5⋯Cl1iv 0.93 2.86 3.774 (7) 170
Symmetry codes: (ii) -x+1, -y, -z+2; (iii) -x+1, -y, -z+1; (iv) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: XSCANS (Siemens, 1996[Siemens (1996). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: XSCANS; data reduction: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); 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; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Noncovalent interactions play an important role in organizing structural units in both natural and artificial systems. Hybrid organic-inorganic compounds are of great interest owing to their ionic, electrical, magnetic and optical properties (Hill, 1998; Kagan et al., 1999; Raptopoulou et al., 2002). Tin metal-halo based hybrids are of particular interest as being materials with interesting optical and magnetic properties (Aruta et al., 2005; Knutson et al., 2005; Mitzi et al., 2001; Kagan et al., 1999). We are currently carrying out studies about lattice including different types of intermolecular interactions. Our strategy is to use aromatic compounds to encourage aryl···aryl packing arrangements of various types, using substituted pyridinium in order to facilitates associations, and halo salts that can involve in X···X interactions as well as X···aryl and X···H interactions. Within our research of hybrid compounds containing tin metal (Al-Far & Ali 2007; Ali, Al-Far & Al-Sou'od, 2007; Ali & Al-Far, 2007; Ali, Al-Far & Ng, 2007), the crystal structure of the title salt, (I), has been investigated.

The asymmetric unit of (I) contains one cation and one-half anion (Fig. 1). The (SnCl6)2- anion lies on an inversion center, in a quasi-octahedral geometry (Table 1). The Sn—Cl bond lengths are almost invariant, but Sn—Cl2 is longer than the others (involved in the shortest hydrogen bonds). These lengths fall within the range of tin-chloride distances reported previously for compounds containing (SnCl6)2- anions (Bouacida et al., 2007; Ellis & Macdonald, 2006; Li et al., 2005; Willett & Haddad, 2000). Bond lengths and angles within the cation are as expected (Allen et al., 1987).

The packing of the structure (Fig. 2) can be described as layers of alternating anions (zigzag orientation) along the face parallel to b-axis and diagonal to ac plane. Each (SnCl6)2- anion is surrounded by six cations via four equatorial (C,N)—H···Cl interactions (Table 2) and two axial Cl···Br interactions [Cl3···Br2i = 3.4393 (15) Å; symmetry code: (i) -1/2 + x, -1/2 - y, -1/2 + z; Fig. 3). This arrangement of molecules appears as layers approximately parallel to [110]. It is noteworthy that structural and theoretical results (Awwadi et al., 2007; and references therein), show the significance of linear C—Y···X- (in this case C—Cl···Br) synthons in influencing structures of crystalline materials and in use as potential building blocks in crystal engineering via supramolecular synthesis.

The intermolecular hydrogen bonds (Table 2) and Cl···Br interactions would therefore add some lattice stability. This is evident in the isostructurality with the reported Te analogue (Fernandes et al., 2004).

Related literature top

The title salt is isomorphous with the Te-analogue, see: Fernandes et al. (2004). For related literature, see: Al-Far & Ali (2007); Ali, Al-Far & Al-Sou'od (2007); Ali & Al-Far (2007); Ali, Al-Far & Ng (2007); Allen et al. (1987); Aruta et al. (2005); Awwadi et al. (2007); Bouacida et al. (2007); Ellis & Macdonald (2006); Hill (1998); Kagan et al. (1999); Knutson et al. (2005); Li et al. (2005); Mitzi et al. (2001); Raptopoulou et al. (2002); Willett & Haddad (2000).

Experimental top

Warm solution of SnCl4 (1.0 mmol) dissolved in absolute ethanol (10 ml) and concentrated HCl (1 ml), was added dropwise to a stirred hot solution of 2-bromopyridine (1 mmol) dissolved in ethanol (10 ml). The mixture was treated with another 2 ml of concentrated HCl and refluxed for 2 h, then cooled, filtered off, and allowed to stand undisturbed at room temperature. The salt crystallized over 1 d as nice yellow block crystals (yield: 89.6%).

Refinement top

H atoms were positioned geometrically, with N—H = 0.86 Å (for NH) and C—H = 0.93 Å for aromatic H, and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C, N).

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS (Siemens, 1996); data reduction: SHELXTL (Sheldrick, 2008); 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. A view of the asymmetric unit of (I), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A packing diagram of (I). Hydrogen bonds and Cl···Br interactions are shown as dashed lines.
[Figure 3] Fig. 3. Part of the cell contents of (I), showing Cl···Br and (C,N)—H···Cl intermolecular interactions (dashed lines) for one (SnCl6)2- anion and six surrounding cations.
Bis(2-bromopyridinium) hexachloridostannate(IV) top
Crystal data top
(C5H5BrN)2[SnCl6]F(000) = 612
Mr = 649.41Dx = 2.222 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 90 reflections
a = 9.0843 (14) Åθ = 1.6–27.4°
b = 10.6827 (9) ŵ = 6.25 mm1
c = 10.6345 (17) ÅT = 296 K
β = 109.843 (11)°Block, yellow
V = 970.8 (2) Å30.20 × 0.15 × 0.10 mm
Z = 2
Data collection top
Siemens P4
diffractometer
1791 independent reflections
Radiation source: fine-focus sealed tube1343 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.048
Detector resolution: 3 pixels mm-1θmax = 25.5°, θmin = 2.8°
ω scansh = 111
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
k = 121
Tmin = 0.340, Tmax = 0.535l = 1212
2385 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)] = 0.040H-atom parameters constrained
wR(F2) = 0.097 w = 1/[σ2(Fo2) + (0.0417P)2 + 0.8983P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
1791 reflectionsΔρmax = 0.61 e Å3
98 parametersΔρmin = 0.73 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0145 (10)
Crystal data top
(C5H5BrN)2[SnCl6]V = 970.8 (2) Å3
Mr = 649.41Z = 2
Monoclinic, P21/nMo Kα radiation
a = 9.0843 (14) ŵ = 6.25 mm1
b = 10.6827 (9) ÅT = 296 K
c = 10.6345 (17) Å0.20 × 0.15 × 0.10 mm
β = 109.843 (11)°
Data collection top
Siemens P4
diffractometer
1791 independent reflections
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
1343 reflections with I > 2σ(I)
Tmin = 0.340, Tmax = 0.535Rint = 0.048
2385 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.097H-atom parameters constrained
S = 1.05Δρmax = 0.61 e Å3
1791 reflectionsΔρmin = 0.73 e Å3
98 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Sn10.00000.00000.50000.0271 (2)
Br20.68293 (9)0.00098 (6)0.92745 (7)0.0595 (3)
Cl10.15178 (16)0.07315 (13)0.36630 (13)0.0376 (4)
Cl20.24265 (16)0.03276 (15)0.68883 (14)0.0474 (4)
Cl30.01440 (19)0.21235 (13)0.42546 (16)0.0500 (4)
N10.8532 (5)0.1873 (5)1.0891 (4)0.0410 (11)
H10.79830.16431.13690.049*
C60.9552 (7)0.2804 (5)1.1327 (6)0.0485 (15)
H60.96550.32031.21300.058*
C51.0445 (8)0.3170 (7)1.0591 (7)0.0612 (19)
H51.11620.38201.08810.073*
C20.8330 (6)0.1285 (5)0.9736 (5)0.0368 (12)
C41.0264 (8)0.2556 (7)0.9409 (7)0.0621 (19)
H41.08800.27820.89040.075*
C30.9181 (7)0.1612 (6)0.8968 (6)0.0518 (16)
H30.90390.12100.81600.062*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Sn10.0278 (3)0.0278 (3)0.0285 (3)0.0023 (2)0.0134 (2)0.0006 (2)
Br20.0574 (5)0.0572 (4)0.0634 (5)0.0230 (3)0.0197 (3)0.0074 (3)
Cl10.0379 (7)0.0438 (7)0.0379 (7)0.0022 (6)0.0216 (6)0.0021 (6)
Cl20.0334 (7)0.0680 (9)0.0382 (8)0.0004 (7)0.0088 (6)0.0147 (7)
Cl30.0604 (10)0.0319 (7)0.0698 (10)0.0009 (7)0.0378 (8)0.0086 (7)
N10.040 (3)0.050 (3)0.035 (2)0.003 (2)0.016 (2)0.001 (2)
C60.042 (3)0.045 (3)0.051 (4)0.000 (3)0.005 (3)0.010 (3)
C50.046 (4)0.050 (4)0.076 (5)0.010 (3)0.005 (3)0.007 (4)
C20.031 (3)0.036 (3)0.041 (3)0.002 (2)0.009 (2)0.001 (2)
C40.050 (4)0.076 (5)0.069 (5)0.013 (4)0.033 (3)0.002 (4)
C30.054 (4)0.062 (4)0.050 (4)0.009 (3)0.031 (3)0.011 (3)
Geometric parameters (Å, º) top
Sn1—Cl12.4216 (13)N1—H10.8600
Sn1—Cl22.4513 (14)C6—C51.362 (9)
Sn1—Cl32.4212 (13)C6—H60.9300
Sn1—Cl1i2.4216 (13)C5—C41.378 (10)
Sn1—Cl2i2.4513 (14)C5—H50.9300
Sn1—Cl3i2.4212 (13)C2—C31.347 (8)
Br2—C21.871 (5)C4—C31.375 (9)
N1—C61.331 (8)C4—H40.9300
N1—C21.336 (7)C3—H30.9300
Cl1—Sn1—Cl289.67 (5)C2—N1—H1118.9
Cl3—Sn1—Cl1i89.70 (5)N1—C6—C5119.6 (6)
Cl3—Sn1—Cl190.30 (5)N1—C6—H6120.2
Cl3—Sn1—Cl290.06 (6)C5—C6—H6120.2
Cl3—Sn1—Cl2i89.94 (6)C6—C5—C4118.6 (6)
Cl1—Sn1—Cl2i90.33 (5)C6—C5—H5120.7
Cl3i—Sn1—Cl3180.0C4—C5—H5120.7
Cl3i—Sn1—Cl1i90.30 (5)N1—C2—C3120.5 (5)
Cl3i—Sn1—Cl189.70 (5)N1—C2—Br2116.4 (4)
Cl1i—Sn1—Cl1180.0C3—C2—Br2123.1 (5)
Cl3i—Sn1—Cl2i90.06 (6)C3—C4—C5120.7 (7)
Cl1i—Sn1—Cl2i89.67 (5)C3—C4—H4119.6
Cl3i—Sn1—Cl289.94 (6)C5—C4—H4119.6
Cl1i—Sn1—Cl290.33 (5)C2—C3—C4118.4 (6)
Cl2i—Sn1—Cl2180.0C2—C3—H3120.8
C6—N1—C2122.3 (5)C4—C3—H3120.8
C6—N1—H1118.9
C2—N1—C6—C50.9 (9)C6—C5—C4—C31.4 (11)
N1—C6—C5—C40.1 (10)N1—C2—C3—C40.6 (9)
C6—N1—C2—C30.7 (9)Br2—C2—C3—C4179.4 (5)
C6—N1—C2—Br2179.4 (4)C5—C4—C3—C21.6 (11)
Symmetry code: (i) x, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Cl2ii0.862.453.234 (5)151
C3—H3···Cl1iii0.932.773.646 (6)158
C5—H5···Cl1iv0.932.863.774 (7)170
Symmetry codes: (ii) x+1, y, z+2; (iii) x+1, y, z+1; (iv) x+3/2, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formula(C5H5BrN)2[SnCl6]
Mr649.41
Crystal system, space groupMonoclinic, P21/n
Temperature (K)296
a, b, c (Å)9.0843 (14), 10.6827 (9), 10.6345 (17)
β (°) 109.843 (11)
V3)970.8 (2)
Z2
Radiation typeMo Kα
µ (mm1)6.25
Crystal size (mm)0.20 × 0.15 × 0.10
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correctionψ scan
(XSCANS; Siemens, 1996)
Tmin, Tmax0.340, 0.535
No. of measured, independent and
observed [I > 2σ(I)] reflections
2385, 1791, 1343
Rint0.048
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.097, 1.05
No. of reflections1791
No. of parameters98
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.61, 0.73

Computer programs: XSCANS (Siemens, 1996), SHELXTL (Sheldrick, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
Sn1—Cl12.4216 (13)Sn1—Cl32.4212 (13)
Sn1—Cl22.4513 (14)
Cl1—Sn1—Cl289.67 (5)Cl3—Sn1—Cl290.06 (6)
Cl3—Sn1—Cl1i89.70 (5)Cl3—Sn1—Cl2i89.94 (6)
Cl3—Sn1—Cl190.30 (5)
Symmetry code: (i) x, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Cl2ii0.862.453.234 (5)151.4
C3—H3···Cl1iii0.932.773.646 (6)158.3
C5—H5···Cl1iv0.932.863.774 (7)169.7
Symmetry codes: (ii) x+1, y, z+2; (iii) x+1, y, z+1; (iv) x+3/2, y+1/2, z+3/2.
 

Acknowledgements

Al al-Bayt University and Al-Balqa'a Applied University are thanked for supporting this work

References

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Volume 64| Part 5| May 2008| Pages m637-m638
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