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Acta Cryst. (2009). E65, m1635-m1636    [ doi:10.1107/S1600536809048971 ]

Bis(2-ethoxycarbonylethyl-[kappa]2C1,O)(2-thioxo-1,3-dithiole-4,5-dithiolato-[kappa]2S4,S5)tin(IV)

G. M. de Lima, S. M. S. V. Wardell, J. L. Wardell and E. R. T. Tiekink

Abstract top

In the title compound, [Sn(C5H9O2)2(C3S5)], the immediate environment around the Sn centre is defined by two S and two C atoms that define an approximately tetrahedral geometry. The close approach of the pendant carbonyl O atoms [Sn-O = 2.577 (3) and 2.573 (3) Å] increases the coordination number to six. Supramolecular chains are formed along the a axis in the crystal structure owing to the presence of C-H...O contacts.

Comment top

Functionally substituted-alkyl-tin compounds, X3SnCR2CH2CO2R' and X2Sn(CR2CH2CO2R')2 (X = halide, R = H or alkyl; R' = alkyl or aryl), are readily available from reactions first reported in the 1970's (Hutton & Oakes, 1976), starting from R2CCHCOY (Y = R' or OR'), HX and SnX2 (for X3SnCR2CH2COY compounds) or HX and tin (for X2Sn(CR2CH2COY)2 substrates). Original interest with these compounds was primarily concerned with their industrial potential as precursors of PVC stabilizers (Lanigen & Weinberg, 1976) but also with regard to their coordination chemistry. Although the potential for use in PVC stabilization has not been realised commercially, the interest in the coordination chemistry, generally of compounds containing SnCR2CH2COY moieties, has been maintained over the succeeding decades. Particular interest has been paid to coordination modes of the CR2CH2COY ligands (de Lima et al. 2009; Tian et al., 2005; Milne et al., 2005; Harrison et al., 1979). Diester-tin compounds, (MeO2CCH2CH2)2SnX2 (X = halide or thiocyanate) (Balasubramanian et al., 1997; Harrison et al., 1979) and (MeO2CCH2CH2)2Sn(dmit) (dmit = 1,3-dithiole-2-thione-4,5-dithiolato; Buchanan et al., 1996) have been shown to be molecular species with hexa-coordinate tin centres both in the solid-state and in non-coordinating solutions, as a consequence of the (C,O)-chelating ligands. Compounds (MeCOCH2CMe2)SnX2 also contain contain hexa-co-ordinate tin centres (X = Cl or dmit; Howie & Wardell, 2001).

The molecular structure of (I) features a chelating dmit ligand as well as two C-bound CH2CH2CO2Et ligands, each of which coordinates via the α carbon atom. The Sn atom exists within a distorted tetrahedral C2S2 donor set, Fig. 1. Significant distortions from the ideal geometry arise from the close approach of two carbonyl-O atoms [Sn—O = 2.577 (3) and 2.573 (3) Å] thereby increasing the coordination number to six. The expanded geometry is therefore based on a highly distorted octahedron. The dmit ligand forms nearly equivalent Sn–S bond distances of 2.4805 (11) and 2.4958 (9) Å. In many respects, the molecular structure of (I) resembles that of the previously reported methyl ester analogue (Buchanan et al. (1996). The former has crystallographic twofold symmetry which is absent in (I) owing to a misalignment of the ethyl substituents.

In the crystal structure, molecules are connected into a supramolecular chain along the a axis via C–H···O interactions, with each molecule forming two donor and two acceptor contacts, Table 1 and Fig. 2.

Related literature top

For original industrial interest in functionally substituted-alkyl-tin compounds, see: Lanigen & Weinberg (1976). For studies concerning the coordination chemistry of functionally substituted-alkyl-tin compounds, see: Harrison et al. (1979); Balasubramanian et al. (1997); Milne et al. (2005); Tian et al. (2005); de Lima et al. (2009). For related structures of functionally substituted-alkyl-tin compounds, see: Buchanan et al. (1996); Howie & Wardell, (2001). For the synthesis, see: Hutton & Oakes (1976); Valade et al. (1985).

Experimental top

Solutions of Cl2Sn(CH2CH2CO2Et)2 (0.75 g, 2 mmol) (Hutton & Oakes, 1976) in acetone (20 ml) and [NEt4]2[Zn(dmit)2] (0.70 g, 1 mmol) (Valade et al., 1985) in acetone (20 ml) were mixed and the reaction mixture was maintained at room temperature. After 1 h, the reaction mixture was filtered and the filtrate evaporated to leave a solid residue, which after washing with water, was crystallized from acetone to give the title compound as a red-coloured crystalline solid, m.pt. 394–396 K. 1H NMR (CDCl3) δ: 1.25 [t, 3H, J(1H-1H) = 7.2 Hz, Me), 1.93 (t, 2H, J(1H-1H) = 7.2 Hz, J(119Sn-1H) = 84.2 Hz), CH2Sn), 2.96 (t, 2H, J(1H-1H) = 7.2 Hz, J(119Sn-1H) = 137.6 Hz, CH2CH2Sn), 4.20 (q, 2H, J(1H-1H) = 7.2 Hz, OCH2) p.p.m. 13C NMR (CDCl3, 62.9 MHz) δ: 13.9 (CH3), 22.8 [J(119Sn-13C) = 580 Hz, CH2Sn], 28.5 [J(119Sn-13C) = 46 Hz, CH2CH2Sn), 63.6 (OCH2), 129.8 (CC), 181.3 (CO), 210.6 (C S) p.p.m. 119Sn (CD2Cl2, 93.3 MHz) δ: 84.2 p.p.m. IR (KBr): 1680 (νCO), 1437 (νCC), 1031 (νCS), 890 (νC-S), 465 (νC-S) cm-1.

Refinement top

All H atoms were geometrically placed (C–H = 0.98–0.99 Å) and refined as riding with Uiso(H) = 1.2–1.5Ueq(C). Indications for disorder was found in the O2-ethyl group. Multiple sites could not be resolved, however. The O2—C7 and C7—C8 bond distances were refined with the distance restraints of 1.460 ± 0.005 Å and 1.500 ± 0.005 Å, respectively. Further, their anisotropic displacement parameters were constrained to be isotropic with the ISOR command in SHELXL97 (Sheldrick, 2008). The structure was refined as a racemic twin precluding the determination of the absolute structure.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I) showing atom-labelling scheme and displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Supramolecular chain formation along the a axis in (I) mediated by C–H···O contacts (orange dashed lines).
Bis(2-ethoxycarbonylethyl-κ2C1,O)(2-thioxo-1,3-dithiole- 4,5-dithiolato-κ2S4,S5)tin(IV) top
Crystal data top
[Sn(C5H9O2)2(C3S5)]F(000) = 1032
Mr = 517.26Dx = 1.776 Mg m−3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71069 Å
Hall symbol: P 2c -2nCell parameters from 16139 reflections
a = 12.1224 (2) Åθ = 2.9–27.5°
b = 13.3825 (2) ŵ = 1.87 mm−1
c = 11.9228 (2) ÅT = 120 K
V = 1934.21 (5) Å3Block, orange
Z = 40.25 × 0.10 × 0.08 mm
Data collection top
Bruker–Nonius 95mm CCD camera on κ-goniostat
diffractometer		3895 independent reflections
Radiation source: Bruker-Nonius FR591 rotating anode3457 reflections with I > 2σ(I)
graphiteRint = 0.056
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.0°
φ and ω scansh = −15→14
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −17→17
Tmin = 0.025, Tmax = 0.052l = −13→15
14014 measured reflections
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)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.064H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0188P)2 + 0.7375P]
where P = (Fo2 + 2Fc2)/3
3895 reflections(Δ/σ)max = 0.002
211 parametersΔρmax = 0.64 e Å−3
15 restraintsΔρmin = −0.48 e Å−3
Crystal data top
[Sn(C5H9O2)2(C3S5)]V = 1934.21 (5) Å3
Mr = 517.26Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 12.1224 (2) ŵ = 1.87 mm−1
b = 13.3825 (2) ÅT = 120 K
c = 11.9228 (2) Å0.25 × 0.10 × 0.08 mm
Data collection top
Bruker–Nonius 95mm CCD camera on κ-goniostat
diffractometer		3895 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		3457 reflections with I > 2σ(I)
Tmin = 0.025, Tmax = 0.052Rint = 0.056
14014 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.064Δρmax = 0.64 e Å−3
S = 1.04Δρmin = −0.48 e Å−3
3895 reflectionsAbsolute structure: ?
211 parametersFlack parameter: ?
15 restraintsRogers parameter: ?
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 > 2σ(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
Sn0.529829 (17)0.337064 (17)0.45100 (3)0.02754 (8)
S10.53453 (8)0.51943 (8)0.41409 (10)0.0335 (3)
S20.73501 (8)0.33979 (7)0.46792 (12)0.0345 (3)
S30.88592 (8)0.51390 (8)0.48204 (9)0.0346 (3)
S40.72095 (7)0.66289 (7)0.43844 (12)0.0321 (2)
S50.94961 (10)0.72872 (9)0.49178 (10)0.0453 (3)
O10.5826 (3)0.1584 (2)0.5112 (3)0.0379 (7)
O20.6277 (3)0.0814 (3)0.6703 (3)0.0573 (10)
O30.3343 (2)0.3912 (2)0.3931 (2)0.0309 (6)
O40.2446 (2)0.4120 (2)0.2305 (2)0.0360 (7)
C10.6756 (3)0.5390 (3)0.4401 (4)0.0295 (9)
C20.7527 (3)0.4689 (3)0.4608 (5)0.0307 (8)
C30.8572 (3)0.6406 (3)0.4716 (4)0.0313 (10)
C40.4687 (4)0.3126 (4)0.6175 (4)0.0356 (11)
H4A0.46350.37730.65720.043*
H4B0.39380.28340.61340.043*
C50.5442 (4)0.2423 (4)0.6830 (4)0.0417 (11)
H5A0.60800.28070.71190.050*
H5B0.50330.21540.74830.050*
C60.5855 (4)0.1571 (3)0.6132 (4)0.0412 (11)
C70.6762 (6)0.0013 (4)0.6013 (5)0.0691 (19)
H7A0.72020.03130.53990.083*
H7B0.6164−0.03890.56710.083*
C80.7474 (5)−0.0643 (6)0.6694 (5)0.086 (2)
H8A0.8081−0.02500.70120.129*
H8B0.7776−0.11750.62200.129*
H8C0.7040−0.09390.73020.129*
C90.4905 (3)0.2620 (3)0.2973 (3)0.0314 (10)
H9A0.55930.24860.25520.038*
H9B0.45530.19700.31450.038*
C100.4131 (4)0.3238 (3)0.2247 (4)0.0367 (10)
H10A0.45690.37300.18170.044*
H10B0.37580.27920.17040.044*
C110.3272 (3)0.3782 (3)0.2923 (4)0.0301 (9)
C120.1619 (4)0.4726 (4)0.2870 (4)0.0392 (11)
H12A0.14680.44410.36210.047*
H12B0.09240.47100.24340.047*
C130.1992 (4)0.5781 (3)0.2994 (4)0.0445 (11)
H13A0.27060.57960.33790.067*
H13B0.14480.61560.34330.067*
H13C0.20680.60860.22500.067*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Sn0.02877 (12)0.02691 (13)0.02694 (13)−0.00144 (10)0.00049 (14)−0.00137 (15)
S10.0284 (5)0.0272 (5)0.0451 (7)0.0013 (4)−0.0039 (4)0.0017 (4)
S20.0292 (4)0.0272 (5)0.0472 (9)0.0016 (4)−0.0027 (5)0.0020 (6)
S30.0289 (4)0.0381 (5)0.0368 (7)−0.0026 (4)−0.0014 (4)−0.0022 (5)
S40.0363 (4)0.0271 (4)0.0330 (7)−0.0037 (4)0.0001 (5)−0.0019 (5)
S50.0491 (6)0.0502 (7)0.0367 (6)−0.0208 (6)0.0015 (5)−0.0058 (6)
O10.0438 (18)0.0333 (16)0.0365 (19)0.0018 (13)−0.0047 (14)−0.0023 (13)
O20.075 (3)0.049 (2)0.048 (2)0.0012 (18)−0.0188 (18)0.0071 (18)
O30.0315 (13)0.0359 (16)0.0254 (16)0.0003 (13)−0.0035 (12)−0.0002 (13)
O40.0329 (15)0.0445 (19)0.0306 (18)0.0062 (14)−0.0022 (13)−0.0018 (15)
C10.0323 (17)0.0266 (17)0.030 (2)−0.0050 (15)−0.003 (2)0.001 (2)
C20.0297 (16)0.0280 (18)0.034 (2)−0.0046 (14)−0.002 (2)−0.009 (2)
C30.0352 (18)0.038 (2)0.021 (3)−0.0066 (16)0.0031 (17)0.0026 (19)
C40.039 (3)0.035 (3)0.032 (3)−0.0048 (19)0.0015 (18)−0.004 (2)
C50.051 (3)0.047 (3)0.027 (2)−0.010 (2)−0.001 (2)0.004 (2)
C60.042 (3)0.039 (3)0.043 (3)−0.014 (2)−0.005 (2)0.008 (2)
C70.092 (5)0.051 (4)0.065 (4)0.018 (3)−0.031 (4)−0.016 (3)
C80.069 (4)0.121 (7)0.069 (5)0.021 (4)−0.012 (3)−0.022 (4)
C90.034 (2)0.031 (2)0.029 (2)0.0001 (19)0.0013 (18)−0.002 (2)
C100.036 (2)0.046 (3)0.028 (2)0.006 (2)−0.003 (2)−0.003 (2)
C110.031 (2)0.027 (2)0.032 (3)0.0007 (18)−0.0012 (18)0.0004 (18)
C120.032 (2)0.048 (3)0.038 (3)0.007 (2)0.0047 (19)−0.002 (2)
C130.044 (3)0.038 (3)0.051 (3)0.005 (2)0.001 (2)0.006 (2)
Geometric parameters (Å, °) top
Sn—C42.144 (5)C4—H4B0.9900
Sn—C92.144 (4)C5—C61.498 (7)
Sn—S12.4805 (11)C5—H5A0.9900
Sn—S22.4958 (9)C5—H5B0.9900
Sn—O32.573 (3)C7—C81.475 (4)
Sn—O12.577 (3)C7—H7A0.9900
S1—C11.758 (4)C7—H7B0.9900
S2—C21.743 (4)C8—H8A0.9800
S3—C31.735 (4)C8—H8B0.9800
S3—C21.742 (3)C8—H8C0.9800
S4—C31.724 (4)C9—C101.520 (6)
S4—C11.746 (4)C9—H9A0.9900
S5—C31.644 (4)C9—H9B0.9900
O1—C61.217 (5)C10—C111.505 (6)
O2—C61.324 (6)C10—H10A0.9900
O2—C71.474 (4)C10—H10B0.9900
O3—C111.217 (5)C12—C131.490 (6)
O4—C111.323 (5)C12—H12A0.9900
O4—C121.454 (5)C12—H12B0.9900
C1—C21.348 (5)C13—H13A0.9800
C4—C51.527 (6)C13—H13B0.9800
C4—H4A0.9900C13—H13C0.9800
C4—Sn—C9130.01 (17)H5A—C5—H5B107.8
C4—Sn—S1108.82 (14)O1—C6—O2122.4 (5)
C9—Sn—S1108.33 (12)O1—C6—C5122.3 (4)
C4—Sn—S2105.78 (12)O2—C6—C5115.2 (4)
C9—Sn—S2107.32 (11)O2—C7—C8111.0 (5)
S1—Sn—S288.68 (3)O2—C7—H7A109.4
C4—Sn—O388.46 (13)C8—C7—H7A109.4
C9—Sn—O372.38 (13)O2—C7—H7B109.4
S1—Sn—O372.34 (7)C8—C7—H7B109.4
S2—Sn—O3159.35 (7)H7A—C7—H7B108.0
C4—Sn—O171.72 (15)C7—C8—H8A109.5
C9—Sn—O181.87 (14)C7—C8—H8B109.5
S1—Sn—O1163.04 (7)H8A—C8—H8B109.5
S2—Sn—O175.14 (7)C7—C8—H8C109.5
O3—Sn—O1124.38 (9)H8A—C8—H8C109.5
C1—S1—Sn97.92 (13)H8B—C8—H8C109.5
C2—S2—Sn97.66 (11)C10—C9—Sn111.7 (3)
C3—S3—C298.14 (18)C10—C9—H9A109.3
C3—S4—C197.73 (18)Sn—C9—H9A109.3
C6—O1—Sn107.4 (3)C10—C9—H9B109.3
C6—O2—C7115.0 (4)Sn—C9—H9B109.3
C11—O3—Sn106.9 (2)H9A—C9—H9B108.0
C11—O4—C12117.1 (3)C11—C10—C9112.7 (4)
C2—C1—S4116.4 (3)C11—C10—H10A109.1
C2—C1—S1127.1 (3)C9—C10—H10A109.1
S4—C1—S1116.5 (2)C11—C10—H10B109.1
C1—C2—S3115.4 (3)C9—C10—H10B109.1
C1—C2—S2127.9 (3)H10A—C10—H10B107.8
S3—C2—S2116.7 (2)O3—C11—O4123.7 (4)
S5—C3—S4124.2 (2)O3—C11—C10123.2 (4)
S5—C3—S3123.6 (2)O4—C11—C10113.1 (4)
S4—C3—S3112.2 (2)O4—C12—C13111.4 (4)
C5—C4—Sn111.2 (3)O4—C12—H12A109.3
C5—C4—H4A109.4C13—C12—H12A109.3
Sn—C4—H4A109.4O4—C12—H12B109.3
C5—C4—H4B109.4C13—C12—H12B109.3
Sn—C4—H4B109.4H12A—C12—H12B108.0
H4A—C4—H4B108.0C12—C13—H13A109.5
C6—C5—C4112.6 (4)C12—C13—H13B109.5
C6—C5—H5A109.1H13A—C13—H13B109.5
C4—C5—H5A109.1C12—C13—H13C109.5
C6—C5—H5B109.1H13A—C13—H13C109.5
C4—C5—H5B109.1H13B—C13—H13C109.5
C4—Sn—S1—C199.3 (2)Sn—S2—C2—S3174.2 (3)
C9—Sn—S1—C1−114.8 (2)C1—S4—C3—S5−176.2 (3)
S2—Sn—S1—C1−6.96 (17)C1—S4—C3—S33.4 (3)
O3—Sn—S1—C1−178.67 (18)C2—S3—C3—S5176.1 (3)
O1—Sn—S1—C110.3 (3)C2—S3—C3—S4−3.5 (3)
C4—Sn—S2—C2−102.3 (2)C9—Sn—C4—C594.0 (3)
C9—Sn—S2—C2115.7 (2)S1—Sn—C4—C5−129.9 (3)
S1—Sn—S2—C26.90 (19)S2—Sn—C4—C5−35.8 (3)
O3—Sn—S2—C229.8 (3)O3—Sn—C4—C5159.3 (3)
O1—Sn—S2—C2−168.0 (2)O1—Sn—C4—C532.2 (3)
C4—Sn—O1—C6−24.6 (3)Sn—C4—C5—C6−40.7 (5)
C9—Sn—O1—C6−161.6 (3)Sn—O1—C6—O2−168.4 (4)
S1—Sn—O1—C670.1 (4)Sn—O1—C6—C59.8 (5)
S2—Sn—O1—C688.0 (3)C7—O2—C6—O13.0 (7)
O3—Sn—O1—C6−99.5 (3)C7—O2—C6—C5−175.4 (5)
C4—Sn—O3—C11−156.3 (3)C4—C5—C6—O117.7 (6)
C9—Sn—O3—C11−23.1 (3)C4—C5—C6—O2−163.9 (4)
S1—Sn—O3—C1193.4 (3)C6—O2—C7—C8164.1 (5)
S2—Sn—O3—C1169.3 (4)C4—Sn—C9—C10102.9 (4)
O1—Sn—O3—C11−89.7 (3)S1—Sn—C9—C10−33.2 (3)
C3—S4—C1—C2−2.0 (4)S2—Sn—C9—C10−127.7 (3)
C3—S4—C1—S1178.3 (3)O3—Sn—C9—C1030.6 (3)
Sn—S1—C1—C26.4 (5)O1—Sn—C9—C10160.7 (3)
Sn—S1—C1—S4−173.9 (2)Sn—C9—C10—C11−38.3 (4)
S4—C1—C2—S3−0.2 (5)Sn—O3—C11—O4−169.2 (3)
S1—C1—C2—S3179.5 (3)Sn—O3—C11—C109.5 (5)
S4—C1—C2—S2−179.9 (3)C12—O4—C11—O33.7 (6)
S1—C1—C2—S2−0.2 (7)C12—O4—C11—C10−175.2 (4)
C3—S3—C2—C12.3 (4)C9—C10—C11—O316.6 (6)
C3—S3—C2—S2−178.0 (3)C9—C10—C11—O4−164.6 (4)
Sn—S2—C2—C1−6.1 (5)C11—O4—C12—C1381.2 (5)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C12—H12a···O1i0.992.383.338 (6)164
C7—H7a···O3ii0.992.463.450 (7)178
Symmetry codes: (i) x−1/2, −y+1/2, z; (ii) x+1/2, −y+1/2, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C12—H12a···O1i0.992.383.338 (6)164
C7—H7a···O3ii0.992.463.450 (7)178
Symmetry codes: (i) x−1/2, −y+1/2, z; (ii) x+1/2, −y+1/2, z.
Acknowledgements top

The use of the EPSRC X-ray crystallographic service at the University of Southampton, England and the valuable assistance of the staff there is gratefully acknowledged. JLW acknowledges support from FAPEMIG (Brazil).

references
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