Crystal structure of 2-methyl-1H-imidazol-3-ium aqua­tri­chlorido­(oxalato-κ2O,O′)stannate(IV)

Diop, M.B.; Diop, L.; Plasseraud, L.; Maris, T.

doi:10.1107/S2056989015005988

research communications

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ISSN: 2056-9890

Volume 71| Part 5| May 2015| Pages 520-522

https://doi.org/10.1107/S2056989015005988

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Crystal structure of 2-methyl-1H-imidazol-3-ium aquatrichlorido(oxalato-κ²O,O′)stannate(IV)

Mouhamadou Birame Diop,^a ^* Libasse Diop,^a Laurent Plasseraud ^b and Thierry Maris ^c

^aLaboratoire de Chimie Minérale et Analytique, Département de Chimie, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal, ^bICMUB UMR 6302, Université de Bourgogne, Faculté des Sciences, 9 avenue Alain Savary, 21000 Dijon, France, and ^cDépartement de Chimie, Université de Montréal, 2900 Boulevard Édouard-Montpetit, Montréal, Québec, H3C 3J7, Canada
^*Correspondence e-mail: dlibasse@gmail.com

Edited by M. Weil, Vienna University of Technology, Austria (Received 12 March 2015; accepted 24 March 2015; online 22 April 2015)

The tin(IV) atom in the complex anion of the title salt, (C₄H₇N₂)[Sn(C₂O₄)Cl₃(H₂O)], is in a distorted octahedral coordination environment defined by three chlorido ligands, an oxygen atom from a water molecule and two oxygen atoms from a chelating oxalate anion. The organic cation is linked through a bifurcated N—H⋯O hydrogen bond to the free oxygen atoms of the oxalate ligand of the complex [Sn(H₂O)Cl₃(C₂O₄)]⁻ anion. Neighbouring stannate(IV) anions are linked through O—H⋯O hydrogen bonds involving the water molecule and the two non-coordinating oxalate oxygen atoms. In combination with additional N—H⋯Cl hydrogen bonds between cations and anions, a three-dimensional network is spanned.

Keywords: crystal structure; organotin(IV) complex; hydrogen bonds.

CCDC reference: 1056053

1. Chemical Context

With many applications found in catalysis (see, for example: Meneghetti & Meneghetti, 2015 ) or as a result of their biological activities (Sirajuddin et al., 2014 ), organotin(IV) complexes are still a widely studied class of compounds. For more than two decades, the Senegalese group has focused research on attempts to obtain new halo- and organotin(IV) compounds, especially compounds with oxalato ligands (Gueye et al., 2010 , 2012 , 2014 ; Sarr et al., 2015 ; Sow et al., 2012 , 2013 ).

In this communication we report on the interaction between methyl-2-imidazolium hydrogenoxalate dihydrate and SnCl₂·2H₂O in methanolic solution, which yielded the title compound, (C₄H₇N₂)[Sn(C₂O₄)Cl₃(H₂O)].

2. Structural commentary

The oxalate anion chelates the [SnCl₃(H₂O)]⁺ moiety and completes a distorted octahedral environment around the tin(IV) atom in the anion (Fig. 1). The Sn—Cl distances [2.359 (2)–2.378 (3) Å] and the Sn—O distances [2.097 (6) Å and 2.111 (6) Å] are similar to those reported for the same anion in ((H₃C)₄N)[Sn(H₂O)Cl₃(C₂O₄)] (Sow et al., 2013). The pairwise distribution of C—O bond lengths with two shorter [1.235 (12)/1.243 (12) Å for O3/O4] and two longer bonds [1.277 (11)/1.282 (12) Å for O1/O2] is attributed to additional bonding to the Sn^IV atom for the longer bonds. The water molecule is trans to one of the Cl atoms and the Sn—O5 bond linking the water molecule to the tin(IV) atom [2.124 (7) Å] is slightly longer than the Sn—O bonds involving the oxalate O atoms. The angles in the [Sn(H₂O)Cl₃(C₂O₄)]⁻ anion and in the organic cation have typical values.

Figure 1
The molecular components of the title compound, with atom labels and 50% displacement ellipsoids at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.

3. Supramolecular features

Each complex [Sn(H₂O)Cl₃(C₂O₄)]⁻ anion is linked with two other anions through O—H⋯O hydrogen bonds between the water molecules as donor and non-coordinating oxalate O atoms as acceptor groups (Table 1). The cations are connected to the anions through a bifurcated N—H⋯O hydrogen bond. Additional N—H⋯Cl hydrogen bonding between cations and anions stabilizes this three-dimensional arrangement (Table 1, Fig. 2). Topological analysis according to TOPOS (Alexandrov et al., 2011 ) reveals a net with 3,5T1 topological type (Fig. 3).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5A⋯O4ⁱ	0.87	1.76	2.618 (9)	170
O5—H5B⋯O3ⁱⁱ	0.87	1.83	2.602 (9)	146
N1—H1⋯O3	0.88	2.32	3.010 (11)	136
N1—H1⋯O4	0.88	2.31	2.974 (10)	132
N2—H2⋯Cl2ⁱⁱⁱ	0.88	2.70	3.354 (8)	132
N2—H2⋯Cl1^iv	0.88	2.84	3.435 (10)	126
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x, -y+2, -z+1; (iii) x, y-1, z+1; (iv) -x+1, -y+1, -z+1.

Figure 2
View approximately around the b axis showing a central complex anion acting as a hydrogen-bond donor toward two other anions and as a hydrogen-bond acceptor of three methyl-2-imidazolium cations.

Figure 3
The 3,5T1 topological network in the structure of the title compound. The purple nodes correspond to the Sn^IV atoms while the blue nodes are the centres of the organic cations.

4. Database Survey

A search of the Cambridge Structural Database (Version 5.36 with one update, Groom & Allen, 2014 ) returned about 50 different structures with bidentate oxalate anions linked to a Sn^IV atom, from which 23 have their oxalate anions acting as bridging ligands, while 20 have the same configuration as in the title compound with a pairwise distribution of C—O bond lengths. Four structures include both configurations, see, for example: Gueye et al. (2010) or Ng et al. (1992 ).

5. Synthesis and crystallization

Crystals of methyl-2-imidazolium hydrogenoxalate dihydrate (L) were obtained by mixing methyl-2-imidazole with oxalic acid in a 1:1 ratio in water and evaporation of the solvent at 333 K. On allowing (L) to react with SnCl₂·2H₂O in a 1:2 ratio in methanol, crystals of (C₄H₇N₂)⁺[Sn(H₂O)Cl₃(C₂O₄)]⁻ were obtained after slow solvent evaporation at room temperature.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms of the water molecules were obtained from a difference map and were refined with an O—H distance of 0.87 Å and U_iso(H) = 1.5U_eq(O). The other H atoms were positioned geometrically (C—H = 0.95 for aromatic and 0.98 Å for methyl groups; N—H = 0.88 Å) and refined as riding with U_iso(H) = xU_eq(C,N) with x = 1.5 for methyl and x = 1.2 for all other H atoms.

Table 2
Experimental details

Crystal data
Chemical formula	(C₄H₇N₂)[Sn(C₂O₄)Cl₃(H₂O)]
M_r	414.19
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	120
a, b, c (Å)	7.4757 (9), 8.0857 (10), 11.2846 (14)
α, β, γ (°)	80.856 (8), 83.946 (9), 86.587 (8)
V (Å³)	669.05 (14)
Z	2
Radiation type	Ga Kα, λ = 1.34139 Å
μ (mm⁻¹)	13.92
Crystal size (mm)	0.05 × 0.04 × 0.04

Data collection
Diffractometer	Bruker Venture Metaljet
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.133, 0.255
No. of measured, independent and observed [I > 2σ(I)] reflections	5497, 2520, 1604
R_int	0.112
(sin θ/λ)_max (Å⁻¹)	0.619

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.062, 0.150, 1.07
No. of reflections	2520
No. of parameters	156
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.10, −1.23
Computer programs: APEX2 and SAINT (Bruker, 2014 ), SHELXT (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ), OLEX2 (Dolomanov et al., 2009 ), Mercury (Macrae et al., 2008 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1056053

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989015005988/wm5136sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015005988/wm5136Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and publCIF (Westrip, 2010).

2-Methyl-1H-imidazol-3-ium aquatrichlorido(oxalato-κ²O,O')stannate(IV) top

Crystal data top

(C₄H₇N₂)[Sn(C₂O₄)Cl₃(H₂O)]	Z = 2
M_r = 414.19	F(000) = 400
Triclinic, P1	D_x = 2.056 Mg m⁻³
a = 7.4757 (9) Å	Ga Kα radiation, λ = 1.34139 Å
b = 8.0857 (10) Å	Cell parameters from 2537 reflections
c = 11.2846 (14) Å	θ = 3.5–53.3°
α = 80.856 (8)°	µ = 13.92 mm⁻¹
β = 83.946 (9)°	T = 120 K
γ = 86.587 (8)°	Block, clear light colourless
V = 669.05 (14) Å³	0.05 × 0.04 × 0.04 mm

Data collection top

Bruker Venture Metaljet diffractometer	2520 independent reflections
Radiation source: Metal Jet, Gallium Liquid Metal Jet Source	1604 reflections with I > 2σ(I)
Helios MX Mirror Optics monochromator	R_int = 0.112
Detector resolution: 10.24 pixels mm^-1	θ_max = 56.1°, θ_min = 4.8°
ω and φ scans	h = −8→9
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −9→9
T_min = 0.133, T_max = 0.255	l = −12→13
5497 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.062	H-atom parameters constrained
wR(F²) = 0.150	w = 1/[σ²(F_o²) + (0.0517P)² + 1.7851P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max < 0.001
2520 reflections	Δρ_max = 2.10 e Å⁻³
156 parameters	Δρ_min = −1.23 e Å⁻³
0 restraints

Special details top

Experimental. X-ray crystallographic data for I were collected from a single-crystal sample, which was mounted on a loop fiber. Data were collected using a Bruker Venture diffractometer equipped with a Photon 100 CMOS Detector, a Helios MX optics and a Kappa goniometer. The crystal-to-detector distance was 4.0 cm, and the data collection was carried out in 1024 x 1024 pixel mode.

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.

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

	x	y	z	U_iso*/U_eq
Sn1	0.29887 (9)	0.93269 (8)	0.27360 (5)	0.0317 (2)
Cl2	0.0743 (4)	1.0116 (3)	0.1403 (2)	0.0435 (6)
Cl3	0.3305 (4)	0.6485 (3)	0.2412 (2)	0.0440 (6)
Cl1	0.5565 (3)	1.0303 (3)	0.1490 (2)	0.0408 (6)
O1	0.4545 (9)	0.8696 (8)	0.4197 (5)	0.0350 (16)
O5	0.2658 (9)	1.1790 (8)	0.3182 (6)	0.0353 (16)
H5A	0.3590	1.2042	0.3507	0.053*
H5B	0.1714	1.1866	0.3693	0.053*
O3	0.0676 (9)	0.7477 (9)	0.6101 (6)	0.0382 (16)
O2	0.0984 (9)	0.8685 (8)	0.4173 (5)	0.0346 (15)
O4	0.4338 (9)	0.7392 (9)	0.6108 (6)	0.0384 (17)
N1	0.2275 (12)	0.5715 (10)	0.8327 (7)	0.042 (2)
H1	0.2288	0.6585	0.7749	0.050*
C1	0.3663 (13)	0.8049 (12)	0.5176 (9)	0.035 (2)
C5	0.2088 (13)	0.4176 (12)	0.8164 (9)	0.034 (2)
C2	0.1599 (14)	0.8079 (13)	0.5178 (9)	0.038 (2)
N2	0.2132 (12)	0.3254 (11)	0.9248 (7)	0.046 (2)
H2	0.2019	0.2162	0.9399	0.055*
C3	0.2380 (15)	0.4238 (12)	1.0101 (9)	0.041 (3)
H3	0.2481	0.3874	1.0935	0.050*
C4	0.2450 (16)	0.5808 (14)	0.9517 (9)	0.044 (3)
H4	0.2592	0.6791	0.9854	0.053*
C6	0.1870 (14)	0.3569 (13)	0.7014 (9)	0.040 (2)
H6A	0.0680	0.3939	0.6757	0.060*
H6B	0.1982	0.2342	0.7134	0.060*
H6C	0.2804	0.4026	0.6393	0.060*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Sn1	0.0409 (4)	0.0320 (4)	0.0223 (4)	−0.0033 (3)	−0.0078 (2)	−0.0003 (3)
Cl2	0.0552 (15)	0.0464 (15)	0.0291 (13)	−0.0117 (12)	−0.0202 (11)	0.0076 (12)
Cl3	0.0584 (15)	0.0350 (14)	0.0407 (14)	−0.0062 (12)	−0.0077 (12)	−0.0090 (12)
Cl1	0.0482 (13)	0.0417 (14)	0.0302 (12)	−0.0063 (11)	0.0016 (11)	−0.0003 (11)
O1	0.049 (4)	0.037 (4)	0.020 (3)	−0.012 (3)	−0.010 (3)	0.004 (3)
O5	0.038 (4)	0.039 (4)	0.029 (4)	−0.006 (3)	−0.003 (3)	−0.005 (3)
O3	0.037 (4)	0.042 (4)	0.029 (4)	0.002 (3)	−0.001 (3)	0.014 (3)
O2	0.049 (4)	0.034 (4)	0.021 (3)	0.005 (3)	−0.005 (3)	−0.004 (3)
O4	0.041 (4)	0.042 (4)	0.031 (4)	−0.007 (3)	−0.020 (3)	0.012 (3)
N1	0.061 (6)	0.029 (5)	0.033 (5)	−0.013 (4)	−0.011 (4)	0.010 (4)
C1	0.046 (6)	0.030 (5)	0.033 (6)	−0.018 (5)	0.005 (5)	−0.010 (5)
C5	0.038 (5)	0.033 (5)	0.032 (5)	−0.003 (4)	−0.005 (4)	−0.003 (5)
C2	0.048 (6)	0.031 (6)	0.037 (6)	0.002 (5)	−0.012 (5)	−0.005 (5)
N2	0.066 (6)	0.032 (5)	0.035 (5)	0.000 (4)	0.002 (4)	0.003 (4)
C3	0.072 (7)	0.025 (5)	0.026 (5)	0.004 (5)	−0.012 (5)	0.003 (5)
C4	0.068 (7)	0.035 (6)	0.031 (6)	−0.011 (5)	−0.005 (5)	−0.007 (5)
C6	0.049 (6)	0.038 (6)	0.035 (6)	0.001 (5)	−0.012 (5)	−0.004 (5)

Geometric parameters (Å, º) top

Sn1—Cl2	2.364 (3)	N1—C5	1.304 (13)
Sn1—Cl3	2.378 (3)	N1—C4	1.377 (12)
Sn1—Cl1	2.359 (2)	C1—C2	1.542 (14)
Sn1—O1	2.097 (6)	C5—N2	1.330 (12)
Sn1—O5	2.124 (7)	C5—C6	1.486 (13)
Sn1—O2	2.111 (6)	N2—H2	0.8800
O1—C1	1.277 (11)	N2—C3	1.375 (12)
O5—H5A	0.8700	C3—H3	0.9500
O5—H5B	0.8691	C3—C4	1.336 (14)
O3—C2	1.235 (12)	C4—H4	0.9500
O2—C2	1.282 (12)	C6—H6A	0.9800
O4—C1	1.243 (12)	C6—H6B	0.9800
N1—H1	0.8800	C6—H6C	0.9800

Cl2—Sn1—Cl3	95.47 (10)	O4—C1—O1	125.3 (9)
Cl1—Sn1—Cl2	100.40 (9)	O4—C1—C2	118.3 (8)
Cl1—Sn1—Cl3	97.56 (9)	N1—C5—N2	105.5 (8)
O1—Sn1—Cl2	168.07 (19)	N1—C5—C6	127.6 (9)
O1—Sn1—Cl3	88.82 (19)	N2—C5—C6	126.9 (9)
O1—Sn1—Cl1	90.03 (18)	O3—C2—O2	125.0 (10)
O1—Sn1—O5	87.8 (3)	O3—C2—C1	119.3 (9)
O1—Sn1—O2	78.6 (3)	O2—C2—C1	115.6 (9)
O5—Sn1—Cl2	87.18 (19)	C5—N2—H2	124.6
O5—Sn1—Cl3	175.21 (18)	C5—N2—C3	110.9 (8)
O5—Sn1—Cl1	85.86 (18)	C3—N2—H2	124.6
O2—Sn1—Cl2	90.23 (19)	N2—C3—H3	127.0
O2—Sn1—Cl3	90.25 (19)	C4—C3—N2	106.0 (9)
O2—Sn1—Cl1	166.09 (18)	C4—C3—H3	127.0
O2—Sn1—O5	85.7 (2)	N1—C4—H4	126.9
C1—O1—Sn1	114.2 (6)	C3—C4—N1	106.1 (10)
Sn1—O5—H5A	110.8	C3—C4—H4	126.9
Sn1—O5—H5B	110.3	C5—C6—H6A	109.5
H5A—O5—H5B	108.2	C5—C6—H6B	109.5
C2—O2—Sn1	114.3 (6)	C5—C6—H6C	109.5
C5—N1—H1	124.2	H6A—C6—H6B	109.5
C5—N1—C4	111.5 (9)	H6A—C6—H6C	109.5
C4—N1—H1	124.2	H6B—C6—H6C	109.5
O1—C1—C2	116.5 (9)

Sn1—O1—C1—O4	170.5 (8)	N1—C5—N2—C3	−0.9 (12)
Sn1—O1—C1—C2	−8.7 (10)	C5—N1—C4—C3	0.6 (13)
Sn1—O2—C2—O3	−172.8 (8)	C5—N2—C3—C4	1.3 (13)
Sn1—O2—C2—C1	4.3 (10)	N2—C3—C4—N1	−1.1 (13)
O1—C1—C2—O3	−179.7 (8)	C4—N1—C5—N2	0.2 (12)
O1—C1—C2—O2	3.0 (13)	C4—N1—C5—C6	−179.8 (10)
O4—C1—C2—O3	1.1 (14)	C6—C5—N2—C3	179.1 (10)
O4—C1—C2—O2	−176.2 (8)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O4ⁱ	0.87	1.76	2.618 (9)	170
O5—H5B···O3ⁱⁱ	0.87	1.83	2.602 (9)	146
N1—H1···O3	0.88	2.32	3.010 (11)	136
N1—H1···O4	0.88	2.31	2.974 (10)	132
N2—H2···Cl2ⁱⁱⁱ	0.88	2.70	3.354 (8)	132
N2—H2···Cl1^iv	0.88	2.84	3.435 (10)	126

Symmetry codes: (i) −x+1, −y+2, −z+1; (ii) −x, −y+2, −z+1; (iii) x, y−1, z+1; (iv) −x+1, −y+1, −z+1.

Acknowledgements

The authors acknowledge the Cheikh Anta Diop University of Dakar (Sénégal), the Canada Foundation for Innovation, Université de Bourgogne and the Université de Montréal for financial support.

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