Dibutyl­bis(3-methyl­sulfanyl-1,2,4-thia­diazole-5-thiolato)tin(IV)

In the title complex, [Sn(C₄H₉)₂(C₃H₃N₂S₃)₂], if weak Sn...N inter­actions are included, the central Sn^IV atom is situated in a skew-trapezoidal bipyramidal geometry, with the basal plane defined by two symmetrically chelating 3-methyl­mercapto-5-mercapto-1,2,4-thia­diazole ligands. The apical positions are occupied by two n-butyl groups. The complex shows a three-dimensional network structure assembled by inter­molecular S...S and C...S non-bonded inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.034
• wR factor = 0.082
• Data-to-parameter ratio = 17.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.97
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C11    -   C12     ..       5.61 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C13    -   C14     ..       5.69 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C9

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

From Fig. 1, it can be seen that, if weak Sn···N interactions are included, the central Sn^IV atom in the title compound, (I), is situated in a skew-trapezoidal bipyramidal geometry, with the basal plane defined by two symmetrically chelating 3-methylmercapto-5-mercapto-1,2,4-thiadiazole ligands. The apical positions are occupied by two n-butyl groups. Fig. 2 illustrates the three-dimensional network structure of the complex, assembled by intermolecular S···S and C···S non-bonded interactions.

The coordination geometry of the Sn atom can be described as distorted trans-octahedral, with atoms N1, N3, S2 and S5 occupying the equatorial positions, and atoms C7 and C11 occupying the axial positions. The molecular structure consists of a monomer with a hexa-coordinated Sn atom surrounded by two S atoms and two N atoms of the ligand, and two n-butyl groups.

Including the weak Sn—N bond, the 3-methylmercapto-5-mercapto-1,2,4-thiadiazole ligand behaves as a bidentate species and chelates to the Sn atom by means of its N and S atoms. The Sn1—S2 and Sn1—S5 bond distances are 2.5061 (14) and 2.5183 (15) Å, respectively, and the weak Sn1—N1 and Sn1—N3 bond lengths are 2.762 (4) and 2.736 (3) Å, respectively.

The bite angles S2—Sn1—N1 and S5—Sn1—N3 of (I) [60.95 (7) and 61.22 (8)°, respectively] can be reconciled with a skew-trapezoidal bipyramidal geometry, although this geometry can also be considered as a distorted trans regular octahedron. The structure of (I) is close to those we have reported previously for analogous compounds? (Ma et al., 2005). There is a good correspondence in their structural parameters: the Sn—S distances lie in the range 2.477–2.526 Å and the Sn—N distances in the range 2.650–2.933 Å. The angles lie in the ranges 59.3–61.53° for S2—Sn1—N1 [59.44 (12)°] and S5—Sn2—N3 [58.99 (12)°], 144.9–149.9° for S2ⁱ—Sn1—N1 [145.15 (11)°] and S5ⁱ—Sn1—N3 [144.57 (12)°], and 122.27–137.24° for C4—Sn1—C5 [123.5 (5)°] and C9—Sn1—C10 [127.0 (5)°] [symmetry code: (i) 2 − x, 1 − y, −z Please check added symmetry code].

From Fig. 2 it can be seen that the complex forms a three-dimensional network structure assembled by intermolecular S2···S2ⁱ and S4···C10ⁱⁱ weak non-bonded interactions between adjacent 3-methylmercapto-5-mercapto-1,2,4-thiadiazole groups [symmetry codes: (i) 2 − x, 1 − y, −z; (ii) 1 + x, y − 1, z]. The S4···C10ⁱⁱ distance is 3.414 Å. The S2···S2ⁱ distance of 3.324 Å is significantly shorter than the sum of the van der Waals radii of two S atoms (3.7 Å; Barone et al., 2001).

S2. Experimental

3-Methylmercapto-5-mercapto-1,2,4-thiadiazole (2 mmol) was added to a solution of sodium ethoxide (2 mmol) in ethanol (20 ml) and the mixture was stirred for 30 min. Bu₂SnCl₂ (1 mmol) was then added to the mixture and the reaction was continued for 12 h at 318 K. After cooling down to room temperature, the mixture was filtered. The solvent of the filtrate was gradually removed by evaporation under vacuum until a solid product was obtained. This solid was then recrystallized from ether–dichloromethane (Ratio?) and colourless crystals of (I) suitable for X-ray diffraction were obtained (m.p. 354 K). Analysis, calculated for C₁₄H₁₄N₄S₆Sn: C 30.06, H 4.32, N 10.01%; found: C 30.13, H 4.29, N 9.96%.

S3. Refinement

All H atoms were positioned geometrically and treated as riding on their parent atoms, with methylene C—H distances of 0.97 Å, and methyl and thiadiazole C—H distances of 0.96 Å. The U_iso(H) values were set at 1.5U_eq(C) for methyl H atoms and at 1.2U_eq(C) for the other H atoms.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The structure of the title complex, showing 30% probability displacement ellipsoids.
	Fig. 2. The crystal packing of the title complex, showing the weak S···S and C···S interactions (dashed lines).

Bis(3-methylmercapto-5-mercapto-1,2,4-thiadiazole)dibutyltin(IV)

Crystal data

[Sn(C4H9)2(C3H3S3N2)2]	Z = 2
Mr = 559.42	F(000) = 564
Triclinic, P1	Dx = 1.598 Mg m^−3
Hall symbol: -P 1	Melting point: 354 K
a = 9.386 (4) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.059 (5) Å	Cell parameters from 4037 reflections
c = 13.561 (6) Å	θ = 2.2–25.0°
α = 77.549 (6)°	µ = 1.64 mm^−1
β = 82.877 (6)°	T = 298 K
γ = 68.646 (6)°	Block, colourless
V = 1162.9 (10) Å^3	0.42 × 0.29 × 0.25 mm

Data collection

Siemens SMART CCD area-detector diffractometer	4037 independent reflections
Radiation source: fine-focus sealed tube	3253 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.019
ϕ and ω scans	θmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→11
Tmin = 0.545, Tmax = 0.684	k = −11→11
6113 measured reflections	l = −14→16

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.082	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0337P)^2 + 0.7694P] where P = (Fo^2 + 2Fc^2)/3
4037 reflections	(Δ/σ)max = 0.001
230 parameters	Δρmax = 0.69 e Å^−3
0 restraints	Δρmin = −0.41 e Å^−3

Special details

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.

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 > σ(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 (Ų)

	x	y	z	Uiso*/Ueq
Sn1	0.94668 (3)	0.69457 (3)	0.18712 (2)	0.05004 (11)
N1	0.6393 (4)	0.8150 (4)	0.1481 (2)	0.0493 (8)
N2	0.3965 (4)	0.8813 (4)	0.0890 (3)	0.0677 (10)
N3	1.1668 (4)	0.6916 (4)	0.3031 (3)	0.0527 (8)
N4	1.3885 (4)	0.6595 (4)	0.3775 (3)	0.0618 (9)
S1	0.50693 (15)	0.75773 (16)	0.02205 (9)	0.0726 (4)
S2	0.85108 (14)	0.61728 (14)	0.05229 (9)	0.0643 (3)
S3	0.42258 (14)	1.01417 (14)	0.23622 (9)	0.0666 (3)
S4	1.44985 (13)	0.55701 (14)	0.28980 (10)	0.0679 (3)
S5	1.22014 (13)	0.53676 (13)	0.15582 (9)	0.0634 (3)
S6	1.12685 (16)	0.83855 (16)	0.45170 (10)	0.0774 (4)
C1	0.6698 (5)	0.7332 (5)	0.0783 (3)	0.0546 (10)
C2	0.4859 (5)	0.8956 (4)	0.1501 (3)	0.0530 (10)
C3	0.2247 (5)	1.1002 (6)	0.2093 (4)	0.0802 (15)
H3A	0.2154	1.1323	0.1376	0.120*
H3B	0.1800	1.1822	0.2426	0.120*
H3C	0.1724	1.0323	0.2332	0.120*
C4	1.2689 (5)	0.6006 (4)	0.2508 (3)	0.0545 (10)
C5	1.2397 (5)	0.7208 (4)	0.3727 (3)	0.0533 (10)
C6	1.2713 (7)	0.8453 (7)	0.5226 (4)	0.0996 (19)
H6A	1.3147	0.7531	0.5660	0.149*
H6B	1.2268	0.9195	0.5628	0.149*
H6C	1.3502	0.8668	0.4771	0.149*
C7	0.9387 (5)	0.9096 (4)	0.1241 (3)	0.0525 (10)
H7A	1.0430	0.9093	0.1136	0.063*
H7B	0.8956	0.9368	0.0582	0.063*
C8	0.8488 (5)	1.0241 (4)	0.1850 (3)	0.0568 (11)
H8A	0.9011	1.0077	0.2462	0.068*
H8B	0.7488	1.0162	0.2045	0.068*
C9	0.8284 (5)	1.1777 (5)	0.1261 (4)	0.0652 (12)
H9A	0.9276	1.1895	0.1145	0.078*
H9B	0.7892	1.1892	0.0607	0.078*
C10	0.7226 (8)	1.2930 (6)	0.1795 (5)	0.115 (2)
H10A	0.6296	1.2734	0.2006	0.173*
H10B	0.6996	1.3854	0.1348	0.173*
H10C	0.7702	1.2948	0.2377	0.173*
C11	0.8633 (6)	0.5974 (5)	0.3267 (3)	0.0655 (12)
H11A	0.7854	0.5619	0.3140	0.079*
H11B	0.9464	0.5155	0.3590	0.079*
C12	0.7924 (7)	0.7130 (6)	0.4000 (4)	0.0856 (16)
H12A	0.8690	0.7527	0.4087	0.103*
H12B	0.7064	0.7924	0.3684	0.103*
C13	0.7415 (8)	0.6518 (7)	0.4978 (4)	0.0975 (19)
H13A	0.8241	0.5668	0.5275	0.117*
H13B	0.6566	0.6220	0.4908	0.117*
C14	0.6918 (8)	0.7629 (8)	0.5658 (5)	0.112 (2)
H14A	0.7764	0.7914	0.5732	0.168*
H14B	0.6581	0.7216	0.6310	0.168*
H14C	0.6092	0.8464	0.5366	0.168*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sn1	0.04718 (18)	0.04949 (18)	0.05419 (18)	−0.01503 (13)	−0.00064 (13)	−0.01536 (13)
N1	0.044 (2)	0.056 (2)	0.0490 (19)	−0.0160 (17)	−0.0046 (15)	−0.0126 (16)
N2	0.054 (2)	0.084 (3)	0.069 (2)	−0.027 (2)	−0.0141 (19)	−0.013 (2)
N3	0.042 (2)	0.050 (2)	0.063 (2)	−0.0084 (16)	−0.0045 (17)	−0.0162 (17)
N4	0.052 (2)	0.058 (2)	0.076 (2)	−0.0165 (19)	−0.0104 (19)	−0.0134 (19)
S1	0.0632 (8)	0.0955 (10)	0.0690 (8)	−0.0292 (7)	−0.0151 (6)	−0.0262 (7)
S2	0.0588 (7)	0.0748 (8)	0.0668 (7)	−0.0209 (6)	−0.0009 (6)	−0.0339 (6)
S3	0.0528 (7)	0.0731 (8)	0.0702 (7)	−0.0124 (6)	−0.0032 (6)	−0.0225 (6)
S4	0.0422 (6)	0.0660 (8)	0.0922 (9)	−0.0073 (6)	−0.0062 (6)	−0.0264 (7)
S5	0.0518 (7)	0.0634 (7)	0.0758 (8)	−0.0112 (6)	−0.0001 (6)	−0.0319 (6)
S6	0.0653 (8)	0.0881 (9)	0.0795 (8)	−0.0134 (7)	−0.0039 (7)	−0.0401 (7)
C1	0.052 (3)	0.065 (3)	0.052 (2)	−0.027 (2)	−0.005 (2)	−0.010 (2)
C2	0.050 (3)	0.052 (3)	0.054 (2)	−0.018 (2)	−0.005 (2)	−0.003 (2)
C3	0.056 (3)	0.085 (4)	0.088 (4)	−0.009 (3)	−0.005 (3)	−0.018 (3)
C4	0.046 (2)	0.047 (2)	0.066 (3)	−0.013 (2)	−0.004 (2)	−0.007 (2)
C5	0.051 (3)	0.046 (2)	0.061 (3)	−0.013 (2)	−0.003 (2)	−0.013 (2)
C6	0.103 (5)	0.117 (5)	0.086 (4)	−0.026 (4)	−0.021 (3)	−0.046 (4)
C7	0.051 (3)	0.050 (2)	0.055 (2)	−0.018 (2)	0.0034 (19)	−0.009 (2)
C8	0.054 (3)	0.053 (3)	0.065 (3)	−0.021 (2)	0.008 (2)	−0.016 (2)
C9	0.062 (3)	0.052 (3)	0.077 (3)	−0.017 (2)	0.007 (2)	−0.013 (2)
C10	0.144 (6)	0.057 (3)	0.131 (5)	−0.027 (4)	0.045 (5)	−0.034 (3)
C11	0.062 (3)	0.075 (3)	0.058 (3)	−0.027 (3)	−0.005 (2)	−0.003 (2)
C12	0.095 (4)	0.108 (4)	0.068 (3)	−0.056 (4)	−0.010 (3)	−0.006 (3)
C13	0.106 (5)	0.105 (5)	0.086 (4)	−0.051 (4)	−0.011 (4)	0.002 (4)
C14	0.128 (6)	0.133 (6)	0.095 (4)	−0.060 (5)	0.021 (4)	−0.051 (4)

Geometric parameters (Å, º)

Sn1—C7	2.125 (4)	C6—H6B	0.9600
Sn1—C11	2.131 (4)	C6—H6C	0.9600
Sn1—S2	2.5060 (14)	C7—C8	1.501 (5)
Sn1—S5	2.5182 (15)	C7—H7A	0.9700
Sn1—N1	2.762 (3)	C7—H7B	0.9700
Sn1—N3	2.735 (3)	C8—C9	1.533 (6)
N1—C1	1.323 (5)	C8—H8A	0.9700
N1—C2	1.371 (5)	C8—H8B	0.9700
N2—C2	1.313 (5)	C9—C10	1.484 (7)
N2—S1	1.661 (4)	C9—H9A	0.9700
N3—C4	1.315 (5)	C9—H9B	0.9700
N3—C5	1.368 (5)	C10—H10A	0.9600
N4—C5	1.309 (5)	C10—H10B	0.9600
N4—S4	1.654 (4)	C10—H10C	0.9600
S1—C1	1.707 (4)	C11—C12	1.598 (7)
S2—C1	1.721 (5)	C11—H11A	0.9700
S3—C2	1.747 (4)	C11—H11B	0.9700
S3—C3	1.787 (5)	C12—C13	1.439 (7)
S4—C4	1.714 (4)	C12—H12A	0.9700
S5—C4	1.732 (4)	C12—H12B	0.9700
S6—C5	1.739 (4)	C13—C14	1.508 (8)
S6—C6	1.785 (5)	C13—H13A	0.9700
C3—H3A	0.9600	C13—H13B	0.9700
C3—H3B	0.9600	C14—H14A	0.9600
C3—H3C	0.9600	C14—H14B	0.9600
C6—H6A	0.9600	C14—H14C	0.9600
C7—Sn1—C11	133.81 (17)	C8—C7—H7A	108.2
C7—Sn1—S2	104.50 (12)	Sn1—C7—H7A	108.2
C11—Sn1—S2	105.46 (13)	C8—C7—H7B	108.2
C7—Sn1—S5	104.84 (12)	Sn1—C7—H7B	108.2
C11—Sn1—S5	107.76 (14)	H7A—C7—H7B	107.4
S2—Sn1—S5	93.08 (5)	C7—C8—C9	112.2 (3)
C7—Sn1—N1	81.94 (13)	C7—C8—H8A	109.2
C11—Sn1—N1	82.83 (15)	C9—C8—H8A	109.2
S2—Sn1—N1	60.96 (7)	C7—C8—H8B	109.2
S5—Sn1—N1	153.98 (7)	C9—C8—H8B	109.2
C1—N1—C2	108.9 (3)	H8A—C8—H8B	107.9
C1—N1—Sn1	87.4 (2)	C10—C9—C8	112.9 (4)
C2—N1—Sn1	163.6 (3)	C10—C9—H9A	109.0
C2—N2—S1	106.7 (3)	C8—C9—H9A	109.0
C4—N3—C5	109.0 (3)	C10—C9—H9B	109.0
C5—N4—S4	107.5 (3)	C8—C9—H9B	109.0
N2—S1—C1	93.7 (2)	H9A—C9—H9B	107.8
C1—S2—Sn1	88.70 (14)	C9—C10—H10A	109.5
C2—S3—C3	101.0 (2)	C9—C10—H10B	109.5
N4—S4—C4	92.9 (2)	H10A—C10—H10B	109.5
C4—S5—Sn1	87.76 (15)	C9—C10—H10C	109.5
C5—S6—C6	100.1 (2)	H10A—C10—H10C	109.5
N1—C1—S1	110.8 (3)	H10B—C10—H10C	109.5
N1—C1—S2	122.9 (3)	C12—C11—Sn1	110.4 (3)
S1—C1—S2	126.3 (3)	C12—C11—H11A	109.6
N2—C2—N1	119.9 (4)	Sn1—C11—H11A	109.6
N2—C2—S3	124.0 (3)	C12—C11—H11B	109.6
N1—C2—S3	116.1 (3)	Sn1—C11—H11B	109.6
S3—C3—H3A	109.5	H11A—C11—H11B	108.1
S3—C3—H3B	109.5	C13—C12—C11	113.0 (5)
H3A—C3—H3B	109.5	C13—C12—H12A	109.0
S3—C3—H3C	109.5	C11—C12—H12A	109.0
H3A—C3—H3C	109.5	C13—C12—H12B	109.0
H3B—C3—H3C	109.5	C11—C12—H12B	109.0
N3—C4—S4	111.1 (3)	H12A—C12—H12B	107.8
N3—C4—S5	122.7 (3)	C12—C13—C14	109.8 (5)
S4—C4—S5	126.2 (3)	C12—C13—H13A	109.7
N4—C5—N3	119.4 (4)	C14—C13—H13A	109.7
N4—C5—S6	123.3 (3)	C12—C13—H13B	109.7
N3—C5—S6	117.3 (3)	C14—C13—H13B	109.7
S6—C6—H6A	109.5	H13A—C13—H13B	108.2
S6—C6—H6B	109.5	C13—C14—H14A	109.5
H6A—C6—H6B	109.5	C13—C14—H14B	109.5
S6—C6—H6C	109.5	H14A—C14—H14B	109.5
H6A—C6—H6C	109.5	C13—C14—H14C	109.5
H6B—C6—H6C	109.5	H14A—C14—H14C	109.5
C8—C7—Sn1	116.2 (3)	H14B—C14—H14C	109.5