A 1:1 adduct between 2,2-bis­(chloro­di­methyl­stannyl)­propane and di­methyl sulfoxide

In the title compound, [Sn₂(CH₃)₄(C₃H₆)Cl₂]·C₂H₆OS, the single di­methyl sulfoxide (DMSO) mol­ecule bridges the two Sn atoms via its O atom [Sn-O distances: 2.578 (2) and 2.632 (2) Å], so that each Sn atom displays distorted trigonal-bipyramidal geometry. The S atom is disordered over two positions with occupancy factors 0.596 (2) and 0.404 (2).

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.004 Å
• Disorder in solvent or counterion
• R factor = 0.026
• wR factor = 0.050
• Data-to-parameter ratio = 35.5

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level B:



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           32.01
         From the CIF: _reflns_number_total               5357
         TEST2: Reflns within _diffrn_reflns_theta_max
         Count of symmetry unique reflns         6174
         Completeness (_total/calc)             86.77%
          Alert B: < 90% complete (theta max?)


 Alert Level C:



PLAT_302  Alert C Anion/Solvent Disorder .......................      20.00 Perc.


 0 Alert Level A = Potentially serious problem

 1 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

S1. Comment

Organotin compounds of the type R₃SnX, where X is an electronegative residue such as halide or trifluoromethanesulfonate, form complexes with donor ligands L in which the Sn atom becomes pentacoordinate. It might thus be expected that compounds of the type XSnR₂(CR'R")_nSnR₂X would form similar complexes in which a ligand L is attached to each Sn atom. However, a study involving DMSO as ligand (Karol et al., 1983) shows that the compound ClSnMe₂CH₂SnMeCl₂ forms a 1:1 complex with DMSO, which bridges the two Sn atoms via its O atom, (I).

It thus seemed of interest to determine whether the replacement of the H atoms of the CH₂ group between the Sn atoms by methyl groups would cause the complex to take up another geometry. Also of interest are variations in the Sn—C—Sn angle, since previous NMR work (Mitchell et al., 1983) indicates that the coupling constant ²J(Sn—C—Sn) changes sign at an angle very close to the tetrahedral angle of 109.47°.

The present results show that 1:1 complexation of DMSO is present in the title compound (I) and that its geometry is broadly similar to that of ClSnMe₂CH₂SnMeCl₂·DMSO, (II). There are however significant differences. While in (II) the angle Sn—C—Sn is 112.0 (6)°, it decreases in (I) to 110.39 (13)°. The Sn—CH₂ bond lengths are of course considerably different in (II): ClMe₂Sn—CH₂ 2.159 (3) and Cl₂MeSn-CH₂ 2.097 (13) Å. In (I), the two bond lengths are as expected almost identical: 2.164 (3) and 2.152 (3) Å. The angle Sn—O—Sn is very similar in (I) and (II): 85.69 (6) and 86.6 (2)°, respectively. However, the Sn—O bond distances differ considerably: 2.578 (2) and 2.632 (2) Å in (I), and 2.568 (8) and 2.575 (8) Å in (II).

S2. Experimental

0,3 g (0,73 mmol) of 2,2-bis(chlorodimethylstannyl)propane (Austin et al., 1986; Karol et al., 1983) were dissolved in 2 ml of dry dimethyl sulfoxide and the mixture stirred for 30 min. The solution was left overnight at 278–288 K. The crystals were separated and dried carefully to remove the solvent from their surface; m.p. 391–392 K, yield 60% [literature (Austin et al., 1986) 389–390 K].

S3. Refinement

Two positions with occupancy factors of 0.596 (2) and 0.404 (2) for S1A and S1B, respectively, were refined for the S atom of the dimethyl sulfoxide moiety. H atoms were placed in calculated positions with U_iso constrained to be 1.5 times U_eq of the carrier atom. For the methyl groups containing atoms C11, C12, C21 and C22, the torsion angles were refined, whereas for the remaining methyl groups AFIX 33 (Sheldrick, 1997) was used. At C4 and at C5 there are two different orientations of the methyl groups having the same site occupation factors as the corresponding positions of the S atom.

Computing details

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Sheldrick, 1991); software used to prepare material for publication: SHELXL97, PARST95 (Nardelli, 1995) and PLATON (Spek, 2001).

Figures

Fig. 1. View of the title compound showing the labelling of all non-H atoms. Displacement ellipsoids are shown at 30% probability levels. The S atom is disordered [two positions with occupancy factors: 0.596 (2) and 0.404 (2)].

(I)

Crystal data

[Sn2(CH3)4(C3H6)Cl2]·C2H6OS	F(000) = 944
Mr = 488.62	Dx = 1.824 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71069 Å
a = 10.7602 (2) Å	Cell parameters from 14885 reflections
b = 9.1559 (2) Å	θ = 3.0–32.0°
c = 18.2953 (3) Å	µ = 3.21 mm^−1
β = 99.2514 (12)°	T = 291 K
V = 1779.00 (6) Å^3	Block, colourless
Z = 4	0.44 × 0.42 × 0.40 mm

Data collection

Nonius KappaCCD diffractometer	3091 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.026
Graphite monochromator	θmax = 32.0°, θmin = 3.0°
Detector resolution: 19 vertical, 18 horizontal pixels mm^-1	h = −15→15
258 frames via ω–rotation (Δω=1%) and two times 15 s per frame (three sets at different κ–angles) scans	k = −10→13
14885 measured reflections	l = −26→26
5357 independent reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.026	H-atom parameters constrained
wR(F^2) = 0.050	w = 1/[σ^2(Fo^2) + (0.0169P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.86	(Δ/σ)max = 0.002
5357 reflections	Δρmax = 0.40 e Å^−3
151 parameters	Δρmin = −0.45 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0230 (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	Occ. (<1)
Sn1	0.356075 (16)	0.071328 (19)	0.097190 (8)	0.04487 (7)
Sn2	0.157803 (16)	0.233913 (19)	0.211282 (9)	0.04547 (7)
Cl11	0.45611 (7)	−0.17218 (8)	0.09939 (4)	0.0694 (2)
Cl21	0.08098 (8)	0.14610 (10)	0.32298 (4)	0.0764 (2)
C1	0.2766 (3)	0.0501 (3)	0.19780 (13)	0.0512 (7)
C2	0.1974 (4)	−0.0899 (3)	0.19404 (18)	0.0936 (13)
H2A	0.2505	−0.1730	0.1905	0.140*
H2B	0.1327	−0.0863	0.1513	0.140*
H2C	0.1595	−0.0978	0.2379	0.140*
C3	0.3855 (3)	0.0424 (4)	0.26284 (15)	0.0818 (11)
H3A	0.3523	0.0353	0.3084	0.123*
H3B	0.4360	0.1289	0.2635	0.123*
H3C	0.4363	−0.0419	0.2574	0.123*
C11	0.2348 (3)	0.0423 (3)	−0.00536 (14)	0.0679 (8)
H11A	0.2646	0.1001	−0.0428	0.102*
H11B	0.1511	0.0725	−0.0004	0.102*
H11C	0.2340	−0.0588	−0.0193	0.102*
C12	0.5262 (3)	0.1934 (3)	0.10703 (16)	0.0643 (8)
H12A	0.5560	0.1941	0.0603	0.096*
H12B	0.5885	0.1495	0.1439	0.096*
H12C	0.5109	0.2919	0.1213	0.096*
C21	−0.0168 (3)	0.2368 (3)	0.13822 (16)	0.0683 (9)
H21A	−0.0702	0.1609	0.1519	0.102*
H21B	−0.0023	0.2210	0.0884	0.102*
H21C	−0.0568	0.3298	0.1414	0.102*
C22	0.2381 (3)	0.4293 (3)	0.25896 (15)	0.0636 (8)
H22A	0.2632	0.4158	0.3113	0.095*
H22B	0.1771	0.5066	0.2504	0.095*
H22C	0.3103	0.4544	0.2368	0.095*
S1A	0.19098 (11)	0.41712 (13)	0.02845 (6)	0.0509 (4)	0.596 (2)
S1B	0.29907 (17)	0.46745 (19)	0.07461 (9)	0.0543 (6)	0.404 (2)
O1	0.24943 (16)	0.32413 (19)	0.09404 (9)	0.0537 (5)
C4	0.1686 (3)	0.5890 (3)	0.06263 (18)	0.0760 (9)
H4A	0.1002	0.5863	0.0905	0.114*	0.596 (2)
H4B	0.1491	0.6564	0.0222	0.114*	0.596 (2)
H4C	0.2440	0.6198	0.0942	0.114*	0.596 (2)
H4D	0.1434	0.6078	0.1098	0.114*	0.404 (2)
H4E	0.0997	0.5456	0.0299	0.114*	0.404 (2)
H4F	0.1921	0.6790	0.0417	0.114*	0.404 (2)
C5	0.3202 (3)	0.4571 (4)	−0.01897 (15)	0.0728 (9)
H5A	0.3451	0.3698	−0.0418	0.109*	0.596 (2)
H5B	0.3897	0.4935	0.0158	0.109*	0.596 (2)
H5C	0.2949	0.5296	−0.0563	0.109*	0.596 (2)
H5D	0.3893	0.3931	−0.0232	0.109*	0.404 (2)
H5E	0.3378	0.5527	−0.0362	0.109*	0.404 (2)
H5F	0.2448	0.4199	−0.0483	0.109*	0.404 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sn1	0.05202 (12)	0.04540 (12)	0.03905 (11)	−0.00190 (8)	0.01297 (8)	−0.00513 (8)
Sn2	0.04644 (12)	0.05031 (13)	0.04082 (11)	0.00041 (8)	0.01048 (8)	−0.00413 (8)
Cl11	0.0801 (5)	0.0543 (5)	0.0759 (5)	0.0135 (4)	0.0195 (4)	−0.0078 (4)
Cl21	0.0776 (5)	0.1009 (7)	0.0579 (4)	0.0079 (5)	0.0329 (4)	0.0109 (4)
C1	0.0681 (18)	0.0420 (16)	0.0473 (14)	0.0059 (14)	0.0205 (14)	0.0035 (12)
C2	0.134 (3)	0.052 (2)	0.115 (3)	−0.020 (2)	0.081 (3)	−0.0053 (18)
C3	0.101 (3)	0.099 (3)	0.0461 (16)	0.045 (2)	0.0157 (17)	0.0113 (16)
C11	0.076 (2)	0.071 (2)	0.0538 (16)	−0.0002 (17)	0.0000 (15)	−0.0169 (14)
C12	0.0597 (19)	0.0600 (19)	0.0751 (19)	−0.0066 (16)	0.0166 (16)	0.0001 (15)
C21	0.0598 (19)	0.083 (2)	0.0589 (17)	−0.0092 (16)	−0.0011 (15)	−0.0018 (15)
C22	0.072 (2)	0.061 (2)	0.0559 (16)	0.0001 (16)	0.0044 (15)	−0.0176 (14)
S1A	0.0519 (8)	0.0569 (8)	0.0446 (7)	−0.0077 (6)	0.0098 (5)	0.0025 (5)
S1B	0.0574 (12)	0.0470 (11)	0.0571 (11)	−0.0070 (9)	0.0047 (9)	0.0058 (8)
O1	0.0692 (13)	0.0460 (11)	0.0498 (10)	0.0018 (9)	0.0215 (9)	0.0058 (8)
C4	0.083 (2)	0.062 (2)	0.087 (2)	0.0162 (18)	0.0231 (19)	0.0145 (17)
C5	0.082 (2)	0.081 (2)	0.0612 (18)	−0.0019 (18)	0.0288 (17)	0.0151 (15)

Geometric parameters (Å, º)

Sn1—C11	2.123 (3)	C21—H21B	0.9600
Sn1—C12	2.128 (3)	C21—H21C	0.9600
Sn1—C1	2.159 (2)	C22—H22A	0.9600
Sn1—Cl11	2.4733 (8)	C22—H22B	0.9600
Sn2—C22	2.113 (3)	C22—H22C	0.9600
Sn2—C21	2.123 (3)	S1A—O1	1.522 (2)
Sn2—C1	2.152 (3)	S1A—C4	1.724 (3)
Sn2—Cl21	2.4594 (7)	S1A—C5	1.791 (3)
C1—C3	1.531 (4)	S1B—O1	1.481 (2)
C1—C2	1.534 (4)	S1B—C5	1.765 (3)
C2—H2A	0.9600	S1B—C4	1.777 (3)
C2—H2B	0.9600	C4—H4A	0.9600
C2—H2C	0.9600	C4—H4B	0.9600
C3—H3A	0.9600	C4—H4C	0.9600
C3—H3B	0.9600	C4—H4D	0.9600
C3—H3C	0.9600	C4—H4E	0.9600
C11—H11A	0.9600	C4—H4F	0.9600
C11—H11B	0.9600	C5—H5A	0.9600
C11—H11C	0.9600	C5—H5B	0.9600
C12—H12A	0.9600	C5—H5C	0.9600
C12—H12B	0.9600	C5—H5D	0.9600
C12—H12C	0.9600	C5—H5E	0.9600
C21—H21A	0.9600	C5—H5F	0.9600
C11—Sn1—C12	122.60 (12)	C5—S1B—C4	97.82 (17)
C11—Sn1—C1	118.09 (11)	S1B—O1—S1A	55.58 (10)
C12—Sn1—C1	115.37 (11)	S1A—C4—S1B	47.14 (10)
C11—Sn1—Cl11	96.06 (8)	S1A—C4—H4A	109.5
C12—Sn1—Cl11	96.08 (8)	S1B—C4—H4A	125.2
C1—Sn1—Cl11	97.80 (7)	S1A—C4—H4B	109.5
C22—Sn2—C21	120.72 (12)	S1B—C4—H4B	124.6
C22—Sn2—C1	119.91 (11)	H4A—C4—H4B	109.5
C21—Sn2—C1	114.80 (11)	S1A—C4—H4C	109.5
C22—Sn2—Cl21	95.94 (8)	S1B—C4—H4C	62.3
C21—Sn2—Cl21	98.37 (8)	H4A—C4—H4C	109.5
C1—Sn2—Cl21	97.17 (7)	H4B—C4—H4C	109.5
C3—C1—C2	110.3 (2)	S1A—C4—H4D	124.5
C3—C1—Sn2	109.95 (18)	S1B—C4—H4D	109.5
C2—C1—Sn2	108.8 (2)	H4A—C4—H4D	34.6
C3—C1—Sn1	107.97 (18)	H4B—C4—H4D	121.2
C2—C1—Sn1	109.29 (17)	H4C—C4—H4D	74.9
Sn2—C1—Sn1	110.56 (11)	S1A—C4—H4E	62.3
C1—C2—H2A	109.5	S1B—C4—H4E	109.5
C1—C2—H2B	109.5	H4A—C4—H4E	74.9
H2A—C2—H2B	109.5	H4B—C4—H4E	74.6
C1—C2—H2C	109.5	H4C—C4—H4E	171.8
H2A—C2—H2C	109.5	H4D—C4—H4E	109.5
H2B—C2—H2C	109.5	S1A—C4—H4F	125.3
C1—C3—H3A	109.5	S1B—C4—H4F	109.5
C1—C3—H3B	109.5	H4A—C4—H4F	120.4
H3A—C3—H3B	109.5	H4B—C4—H4F	34.9
C1—C3—H3C	109.5	H4C—C4—H4F	74.7
H3A—C3—H3C	109.5	H4D—C4—H4F	109.5
H3B—C3—H3C	109.5	H4E—C4—H4F	109.5
Sn1—C11—H11A	109.5	S1B—C5—S1A	46.39 (10)
Sn1—C11—H11B	109.5	S1B—C5—H5A	123.7
H11A—C11—H11B	109.5	S1A—C5—H5A	109.5
Sn1—C11—H11C	109.5	S1B—C5—H5B	63.1
H11A—C11—H11C	109.5	S1A—C5—H5B	109.5
H11B—C11—H11C	109.5	H5A—C5—H5B	109.5
Sn1—C12—H12A	109.5	S1B—C5—H5C	126.0
Sn1—C12—H12B	109.5	S1A—C5—H5C	109.5
H12A—C12—H12B	109.5	H5A—C5—H5C	109.5
Sn1—C12—H12C	109.5	H5B—C5—H5C	109.5
H12A—C12—H12C	109.5	S1B—C5—H5D	109.5
H12B—C12—H12C	109.5	S1A—C5—H5D	125.9
Sn2—C21—H21A	109.5	H5A—C5—H5D	35.1
Sn2—C21—H21B	109.5	H5B—C5—H5D	74.6
H21A—C21—H21B	109.5	H5C—C5—H5D	119.9
Sn2—C21—H21C	109.5	S1B—C5—H5E	109.5
H21A—C21—H21C	109.5	S1A—C5—H5E	123.8
H21B—C21—H21C	109.5	H5A—C5—H5E	122.2
Sn2—C22—H22A	109.5	H5B—C5—H5E	74.2
Sn2—C22—H22B	109.5	H5C—C5—H5E	35.3
H22A—C22—H22B	109.5	H5D—C5—H5E	109.5
Sn2—C22—H22C	109.5	S1B—C5—H5F	109.5
H22A—C22—H22C	109.5	S1A—C5—H5F	63.1
H22B—C22—H22C	109.5	H5A—C5—H5F	74.4
O1—S1A—C4	106.78 (14)	H5B—C5—H5F	172.6
O1—S1A—C5	103.99 (14)	H5C—C5—H5F	74.3
C4—S1A—C5	98.85 (16)	H5D—C5—H5F	109.5
O1—S1B—C5	107.02 (16)	H5E—C5—H5F	109.5
O1—S1B—C4	106.01 (16)