Bis(2-bromo­pyridinium) hexa­chlorido­stannate(IV)

Ali, B.F.; Al-Far, R.; Haddad, S.F.

doi:10.1107/S160053680800901X

metal-organic compounds

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ISSN: 2056-9890

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

doi:10.1107/S160053680800901X

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Bis(2-bromopyridinium) hexachloridostannate(IV)

Basem Fares Ali,^a Rawhi Al-Far ^b ^* and Salim F. Haddad ^c

^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 ). 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

Crystal data

(C₅H₅BrN)₂[SnCl₆]
M_r = 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 ) T_min = 0.340, T_max = 0.535
2385 measured reflections
1791 independent reflections
1343 reflections with I > 2σ(I)
R_int = 0.048

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.097
S = 1.05
1791 reflections
98 parameters
H-atom parameters constrained
Δρ_max = 0.61 e Å⁻³
Δρ_min = −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	D⋯A	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⋯Cl1^iv	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); cell refinement: XSCANS; 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; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680800901X/bh2165sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680800901X/bh2165Isup2.hkl

checkCIF report

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%).

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

	Fig. 1. A view of the asymmetric unit of (I), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A packing diagram of (I). Hydrogen bonds and Cl···Br interactions are shown as dashed lines.
	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
M_r = 649.41	D_x = 2.222 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 90 reflections
a = 9.0843 (14) Å	θ = 1.6–27.4°
b = 10.6827 (9) Å	µ = 6.25 mm⁻¹
c = 10.6345 (17) Å	T = 296 K
β = 109.843 (11)°	Block, yellow
V = 970.8 (2) Å³	0.20 × 0.15 × 0.10 mm
Z = 2

Data collection top

Siemens P4 diffractometer	1791 independent reflections
Radiation source: fine-focus sealed tube	1343 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.048
Detector resolution: 3 pixels mm^-1	θ_max = 25.5°, θ_min = 2.8°
ω scans	h = −1→11
Absorption correction: ψ scan (XSCANS; Siemens, 1996)	k = −12→1
T_min = 0.340, T_max = 0.535	l = −12→12
2385 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.040	H-atom parameters constrained
wR(F²) = 0.097	w = 1/[σ²(F_o²) + (0.0417P)² + 0.8983P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
1791 reflections	Δρ_max = 0.61 e Å⁻³
98 parameters	Δρ_min = −0.73 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0145 (10)

Crystal data top

(C₅H₅BrN)₂[SnCl₆]	V = 970.8 (2) Å³
M_r = 649.41	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.0843 (14) Å	µ = 6.25 mm⁻¹
b = 10.6827 (9) Å	T = 296 K
c = 10.6345 (17) Å	0.20 × 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)
T_min = 0.340, T_max = 0.535	R_int = 0.048
2385 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.097	H-atom parameters constrained
S = 1.05	Δρ_max = 0.61 e Å⁻³
1791 reflections	Δρ_min = −0.73 e Å⁻³
98 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Sn1	0.0000	0.0000	0.5000	0.0271 (2)
Br2	0.68293 (9)	0.00098 (6)	0.92745 (7)	0.0595 (3)
Cl1	0.15178 (16)	0.07315 (13)	0.36630 (13)	0.0376 (4)
Cl2	0.24265 (16)	−0.03276 (15)	0.68883 (14)	0.0474 (4)
Cl3	0.01440 (19)	−0.21235 (13)	0.42546 (16)	0.0500 (4)
N1	0.8532 (5)	0.1873 (5)	1.0891 (4)	0.0410 (11)
H1	0.7983	0.1643	1.1369	0.049*
C6	0.9552 (7)	0.2804 (5)	1.1327 (6)	0.0485 (15)
H6	0.9655	0.3203	1.2130	0.058*
C5	1.0445 (8)	0.3170 (7)	1.0591 (7)	0.0612 (19)
H5	1.1162	0.3820	1.0881	0.073*
C2	0.8330 (6)	0.1285 (5)	0.9736 (5)	0.0368 (12)
C4	1.0264 (8)	0.2556 (7)	0.9409 (7)	0.0621 (19)
H4	1.0880	0.2782	0.8904	0.075*
C3	0.9181 (7)	0.1612 (6)	0.8968 (6)	0.0518 (16)
H3	0.9039	0.1210	0.8160	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Sn1	0.0278 (3)	0.0278 (3)	0.0285 (3)	0.0023 (2)	0.0134 (2)	0.0006 (2)
Br2	0.0574 (5)	0.0572 (4)	0.0634 (5)	−0.0230 (3)	0.0197 (3)	−0.0074 (3)
Cl1	0.0379 (7)	0.0438 (7)	0.0379 (7)	−0.0022 (6)	0.0216 (6)	0.0021 (6)
Cl2	0.0334 (7)	0.0680 (9)	0.0382 (8)	−0.0004 (7)	0.0088 (6)	0.0147 (7)
Cl3	0.0604 (10)	0.0319 (7)	0.0698 (10)	0.0009 (7)	0.0378 (8)	−0.0086 (7)
N1	0.040 (3)	0.050 (3)	0.035 (2)	−0.003 (2)	0.016 (2)	0.001 (2)
C6	0.042 (3)	0.045 (3)	0.051 (4)	0.000 (3)	0.005 (3)	−0.010 (3)
C5	0.046 (4)	0.050 (4)	0.076 (5)	−0.010 (3)	0.005 (3)	0.007 (4)
C2	0.031 (3)	0.036 (3)	0.041 (3)	−0.002 (2)	0.009 (2)	0.001 (2)
C4	0.050 (4)	0.076 (5)	0.069 (5)	−0.013 (4)	0.033 (3)	0.002 (4)
C3	0.054 (4)	0.062 (4)	0.050 (4)	−0.009 (3)	0.031 (3)	−0.011 (3)

Geometric parameters (Å, º) top

Sn1—Cl1	2.4216 (13)	N1—H1	0.8600
Sn1—Cl2	2.4513 (14)	C6—C5	1.362 (9)
Sn1—Cl3	2.4212 (13)	C6—H6	0.9300
Sn1—Cl1ⁱ	2.4216 (13)	C5—C4	1.378 (10)
Sn1—Cl2ⁱ	2.4513 (14)	C5—H5	0.9300
Sn1—Cl3ⁱ	2.4212 (13)	C2—C3	1.347 (8)
Br2—C2	1.871 (5)	C4—C3	1.375 (9)
N1—C6	1.331 (8)	C4—H4	0.9300
N1—C2	1.336 (7)	C3—H3	0.9300

Cl1—Sn1—Cl2	89.67 (5)	C2—N1—H1	118.9
Cl3—Sn1—Cl1ⁱ	89.70 (5)	N1—C6—C5	119.6 (6)
Cl3—Sn1—Cl1	90.30 (5)	N1—C6—H6	120.2
Cl3—Sn1—Cl2	90.06 (6)	C5—C6—H6	120.2
Cl3—Sn1—Cl2ⁱ	89.94 (6)	C6—C5—C4	118.6 (6)
Cl1—Sn1—Cl2ⁱ	90.33 (5)	C6—C5—H5	120.7
Cl3ⁱ—Sn1—Cl3	180.0	C4—C5—H5	120.7
Cl3ⁱ—Sn1—Cl1ⁱ	90.30 (5)	N1—C2—C3	120.5 (5)
Cl3ⁱ—Sn1—Cl1	89.70 (5)	N1—C2—Br2	116.4 (4)
Cl1ⁱ—Sn1—Cl1	180.0	C3—C2—Br2	123.1 (5)
Cl3ⁱ—Sn1—Cl2ⁱ	90.06 (6)	C3—C4—C5	120.7 (7)
Cl1ⁱ—Sn1—Cl2ⁱ	89.67 (5)	C3—C4—H4	119.6
Cl3ⁱ—Sn1—Cl2	89.94 (6)	C5—C4—H4	119.6
Cl1ⁱ—Sn1—Cl2	90.33 (5)	C2—C3—C4	118.4 (6)
Cl2ⁱ—Sn1—Cl2	180.0	C2—C3—H3	120.8
C6—N1—C2	122.3 (5)	C4—C3—H3	120.8
C6—N1—H1	118.9

C2—N1—C6—C5	−0.9 (9)	C6—C5—C4—C3	1.4 (11)
N1—C6—C5—C4	−0.1 (10)	N1—C2—C3—C4	0.6 (9)
C6—N1—C2—C3	0.7 (9)	Br2—C2—C3—C4	−179.4 (5)
C6—N1—C2—Br2	−179.4 (4)	C5—C4—C3—C2	−1.6 (11)

Symmetry code: (i) −x, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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···Cl1^iv	0.93	2.86	3.774 (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]
M_r	649.41
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	9.0843 (14), 10.6827 (9), 10.6345 (17)
β (°)	109.843 (11)
V (Å³)	970.8 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	6.25
Crystal size (mm)	0.20 × 0.15 × 0.10

Data collection
Diffractometer	Siemens P4 diffractometer
Absorption correction	ψ scan (XSCANS; Siemens, 1996)
T_min, T_max	0.340, 0.535
No. of measured, independent and observed [I > 2σ(I)] reflections	2385, 1791, 1343
R_int	0.048
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.097, 1.05
No. of reflections	1791
No. of parameters	98
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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—Cl1	2.4216 (13)	Sn1—Cl3	2.4212 (13)
Sn1—Cl2	2.4513 (14)

Cl1—Sn1—Cl2	89.67 (5)	Cl3—Sn1—Cl2	90.06 (6)
Cl3—Sn1—Cl1ⁱ	89.70 (5)	Cl3—Sn1—Cl2ⁱ	89.94 (6)
Cl3—Sn1—Cl1	90.30 (5)

Symmetry code: (i) −x, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Cl2ⁱⁱ	0.86	2.45	3.234 (5)	151.4
C3—H3···Cl1ⁱⁱⁱ	0.93	2.77	3.646 (6)	158.3
C5—H5···Cl1^iv	0.93	2.86	3.774 (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

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