metal-organic compounds
Hexa-μ2-acetato-hexa-n-butylhexa-μ3-oxido-tin(IV) toluene monosolvate
aInstitut für Chemie neuer Materialien, Anorganische Chemie II, Universität Osnabrück, Barbarastrasse 7, 49069 Osnabrück, Germany
*Correspondence e-mail: hreuter@uni-osnabrueck.de
The title compound, [Sn6(C4H9)6(CH3COO)6O6]·C7H8, has one half-toluene molecule and one half-organotin molecule in the The latter is situated about an inversion centre and belongs to the class of hexameric monoorganooxotin carboxylates with a hexagonal prismatic or `drum-like' motif of the central tin–oxygen core. Two Sn3O3 rings in a flat-chair conformation are linked via six Sn—O bonds and six bridging acetate groups. All Sn atoms have approximate octahedral coordination geometry. The Sn—O bonds which are trans to the alkyl group are significantly shorter than the others. One butyl group is disordered over two different sites, with occupancies of 0.9:0.1. Very large atomic displacement parameters of the toluene molecule indicate an unresolvable disorder about the twofold axis.
Related literature
For an overview of the synthesis of organotin carboxylates, see: Mehrotra & Bohra (1983). For an overview on compositions and structure types of organotin carboxylates, see: Tiekink (1991). For structural details on hexameric, `drum-like' monoorganooxotin acetates, see: Day et al. (1988); Kuan et al. (2002); Beckmann et al. (2004). For `ladder-type' monoorganooxotin carboxylates, see: Day et al. (1988). For the static trans strengthening in alkyltin(IV) halides, see: Buslaev et al. (1989); Reuter & Puff (1992).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008).
Supporting information
https://doi.org/10.1107/S160053681204888X/fj2609sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681204888X/fj2609Isup2.hkl
1.24 g (6 mmol) n-butylstannonic acid (Gelest, Inc.) and 0.36 g (6 mmol) glacial acetic acid (Fluka) were dissolved in 120 ml toluene. The mixture was heated under reflux for 6 h. The water formed in the reaction was removed by a Dean-Stark apparatus. The reaction mixture was filtered and the solvent evaporated overnight at room temperature. After evaporation colourless block shaped crystals was obtained.
1H-NMR (Bruker AVANCE DPX, 250 MHz, CDCl3) δ [p.p.m.]: 0.91 (t, 3H, CH3); 1.57–1.75 (m, 2H); 1.18–1.55 (m, 4H); 2.09 (s, 3H, CH3COO).
{1H}-13C-NMR (Bruker AVANCE DPX, 250 MHz, CDCl3) δ [p.p.m.], nJ(13C-119/117Sn) [Hz]: 26.74 (α-CH2, n = 1, 1191.9/1139.0); 27.02 (β-CH2, n = 2, 57.4); 26.48 (γ-CH2, n = 3, 195.9/187.6); 13.48 (CH3, n = 4, 14.8); 24.22 (CH3—COO); 179.64 (CH3—COO, n = 2, 30.3).
A suitable single-crystal was selected under a polarization microsope and mounted on a 50 µm MicroMesh MiTeGen MicromountTM using FROMBLIN Y perfluoropolyether (LVAC 16/6, Aldrich).
The n-butyl group at Sn3 is statistically disordered resulting in two different conformations with occupancies 0.9/0.1. In order to get a reliable structure model carbon-carbon bonds of the minor part were restraint to a common refined value of 1.516(x) Å and their anisotropic displacement parameters fit to those of the corresponding carbon atoms of the major part. Although the hydrogen atoms of the non-disordered carbon atoms could clearly identified in difference Fourier synthesis, all were idealized and refined at calculated positions riding on the carbon atoms with C—H distances of 0.98 Å (–CH3), 0.98 (–CH2–) and 0.95 Å (Haromatic). Carbon atoms of the solvent molecule show high anisotropic displacement parameters as a result of high thermal motion or more probably as a result of its statistic disorder about the twofold axis giving rise to unusual bond lengths and angles.
The synthesis of organotin(IV) carboxylates is well established since a long time (Mehrotra & Bohra, 1983) and many of their crystal structures have been investigated into detail (Tiekink, 1991). Thus, in the case of triorganotin moieties R3Sn the corresponding carboxylates are of general formula R3Sn(O2CR') with (O2CR') representing the carboxylate ion. Diorganotin oxides, R2SnO, most often insoluble in indifferent organic solvents, can be easily dissolved in a large number of
R'COOH, giving rise to the formation of carboxylates with a lot of different compositions and a tremendous diversity of molecular structures. Applying the same conditions to monoorganotin sesquioxides, RSnO1,5, also insoluble in non-complexing organic solvents results in the formation of monoorganooxotin carboxylates with "ladder"-type structures of composition (RSn)6O4(O2CR')10 (Day et al.,1988) or, more frequently, to hexanuclear compounds [RSnO(O2CR')]6. In the latter case, the structure is dominated by a hexagonal prismatic or "drum"-like arrangement of the tin-oxygen core as was demonstrated in the case of acetates (R' = CH3) for R = iPr (Kuan et al., 2002), R = tmsm (Beckmann et al., 2004), and R = Me (Day et al.,1988). By dissolving n-butylstannonic acid of idealized formula nBuSnO(OH) in a mixture of toluene/acetic acid and removing the resulting water by use of a Dean-Stark apparatus we were able to obtain single crystals of the corresponding R = n-butyl hexamer as the 1:1 toluene solvate, [nBuSnO(OAc)]6 x C7H8.The
of the title compound consists of a centrosymmetric hexamer (Fig. 1) with i at (1/4,3/4,0) and a toluene molecule of 2. As usual for the constitution (Fig. 2) of the drum, the six-membered tin-oxygen rings forming the bases are not planar but adopt a flat chair-conformation with the torsion angles listed in Tab. 1. Both rings are rotated through 60° against each other so that each oxygen atom bonds to a tin atom of the adjacent ring. The six sides of the drum consist of tin oxygen trapezoids with small angles at tin [77.88 (6)° - 78.34 (6)°, mean value 78.0 (2)°] and larger ones at oxygen [99.79 (6)° - 100.55 (6)°, mean value 100.1 (3)°]. These four-membered rings are also non-planar but bent [18.19 (5)°-18.99 (4)°] along the O···O diagonals that are 2.625 (2) - 2.636 (2) Å long in contrast to the Sn··· Sn diagonals that are much more longer [3.1980 (2) - 3.2041 (2) Å]. Both tin atoms of these six four-membered tin oxygen rings are bridged by acetate groups with carbon oxygen distances that are almost equal [1.256 (3) - 1.267 (3) Å, mean value 1.263 (5) Å] indicating their symmetrical coordination mode (Fig. 3).In summary, all tin atoms are octahedrally coordinated by the n-butyl ligand, three oxygen atoms of the drum and two oxygen atoms of two different acetate groups (Fig. 2). The distortions of the octahedra can be described by carbon-tin-oxygen axes that are slightly bent [175.48 (7)° - 177.18 (8)°], and bond angles of the organic groups to their cis-oriented neighboring oxygen atoms that are considerably widened [91.90 (7)° - 100.53 (8)°].
While the tin-carbon bonds are very similar [2.125 (2) to 2.129 (2) Å, mean value: 2.128 (2) Å] tin-oxygen bond lengths fall into two clearly different groups. The longer ones [2.162 (2) - 2.172 (2) Å, mean value: 2.167 (5) Å] are those to the bridging acetate groups. The narrow range is in correspondence with the narrow range of carbon oxygen bonds, described above, indicating a symmetrical bonding of the acetate groups. The shorter ones [2.080 (2) - 2.097 (2) Å] arise from the µ3-oxygen atoms within the drum. They can be subdivided into those that are trans to the organic ligand and significantly shorter [2.080 (2) - 2.085 (2) Å, mean value: 2.083 (3) Å] and those that are somewhat longer arising from the corresponding cis-oriented oxygen atoms [2.0882 (2) - 2.0969 (2) Å, mean value: 2.092 (4) Å]. This strengthening although less marked is similar to the static trans-strengthening observed in the case of alkyl tin halides (Buslaev et al., 1989), Reuter & Puff, 1992).
Intermolecular interactions of the cylindrical hexamers are limited to van-der-Waals ones because the accessibility of the polar tin-oxygen core is restricted (Fig. 4). As a result of these weak interactions, molecules are arranged in planar hexagonal nets (Fig. 5a) with two different orientations of the drum (Fig. 5b). Between these nets large apolar channels with large cavities exist (Fig. 6a) which partially are fulfilled by the solvent molecules (Fig. 6b).
For an overview on the synthesis of organotin carboxylates, see: Mehrotra & Bohra (1983). For an overview on compositions and structure types of organotin carboxylates, see: Tiekink (1991). For structural details on hexameric, "drum"-like monoorganooxotin acetates, see: Day et al. (1988), Kuan et al. (2002), Beckmann et al. (2004). For "ladder" type monoorganooxotin carboxylates, see: Day et al. (1988). For the static trans strengthening in alkyl tin(IV) halides, see: Buslaev et al. (1989); Reuter & Puff (1992).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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: SHELXTL (Sheldrick, 2008).[Sn6(C4H9)6(C2H3O2)6O6]·C7H8 | F(000) = 3128 |
Mr = 1597.21 | Dx = 1.810 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 9091 reflections |
a = 23.4154 (8) Å | θ = 2.6–30.0° |
b = 15.5832 (6) Å | µ = 2.58 mm−1 |
c = 16.1012 (6) Å | T = 150 K |
β = 93.926 (2)° | Block, colourless |
V = 5861.3 (4) Å3 | 0.30 × 0.22 × 0.10 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 6788 independent reflections |
Radiation source: fine-focus sealed tube | 5890 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.035 |
φ and ω scans | θmax = 28.0°, θmin = 2.5° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −30→28 |
Tmin = 0.509, Tmax = 0.783 | k = −20→19 |
76854 measured reflections | l = −20→21 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.020 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.046 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0188P)2 + 9.9195P] where P = (Fo2 + 2Fc2)/3 |
6788 reflections | (Δ/σ)max = 0.002 |
325 parameters | Δρmax = 0.65 e Å−3 |
6 restraints | Δρmin = −0.61 e Å−3 |
[Sn6(C4H9)6(C2H3O2)6O6]·C7H8 | V = 5861.3 (4) Å3 |
Mr = 1597.21 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 23.4154 (8) Å | µ = 2.58 mm−1 |
b = 15.5832 (6) Å | T = 150 K |
c = 16.1012 (6) Å | 0.30 × 0.22 × 0.10 mm |
β = 93.926 (2)° |
Bruker APEXII CCD diffractometer | 6788 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 5890 reflections with I > 2σ(I) |
Tmin = 0.509, Tmax = 0.783 | Rint = 0.035 |
76854 measured reflections |
R[F2 > 2σ(F2)] = 0.020 | 6 restraints |
wR(F2) = 0.046 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.65 e Å−3 |
6788 reflections | Δρmin = −0.61 e Å−3 |
325 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Sn1 | 0.218624 (6) | 0.777418 (9) | 0.142503 (8) | 0.01627 (4) | |
Sn2 | 0.343645 (6) | 0.788062 (10) | 0.073955 (8) | 0.01612 (4) | |
Sn3 | 0.238831 (6) | 0.599363 (9) | 0.049412 (8) | 0.01573 (4) | |
O1 | 0.26833 (6) | 0.86006 (10) | 0.07422 (8) | 0.0175 (3) | |
O2 | 0.28513 (6) | 0.69761 (10) | 0.11156 (8) | 0.0172 (3) | |
O3 | 0.17758 (6) | 0.69645 (10) | 0.05325 (9) | 0.0171 (3) | |
O4 | 0.27161 (7) | 0.81598 (10) | 0.25130 (9) | 0.0228 (4) | |
O5 | 0.35980 (7) | 0.81837 (10) | 0.20439 (9) | 0.0223 (4) | |
C4 | 0.32520 (11) | 0.82347 (14) | 0.26131 (13) | 0.0208 (5) | |
C5 | 0.35026 (11) | 0.84157 (18) | 0.34786 (14) | 0.0309 (6) | |
H5A | 0.3916 | 0.8310 | 0.3507 | 0.064 (3)* | |
H5B | 0.3324 | 0.8040 | 0.3874 | 0.064 (3)* | |
H5C | 0.3432 | 0.9016 | 0.3620 | 0.064 (3)* | |
O6 | 0.39045 (7) | 0.90787 (10) | 0.06712 (9) | 0.0212 (3) | |
O7 | 0.33111 (7) | 0.98846 (10) | −0.01633 (9) | 0.0204 (3) | |
C6 | 0.37742 (10) | 0.97521 (15) | 0.02701 (13) | 0.0194 (5) | |
C7 | 0.42114 (11) | 1.04577 (16) | 0.03037 (15) | 0.0276 (5) | |
H7A | 0.4479 | 1.0365 | −0.0130 | 0.064 (3)* | |
H7B | 0.4422 | 1.0458 | 0.0851 | 0.064 (3)* | |
H7C | 0.4019 | 1.1011 | 0.0212 | 0.064 (3)* | |
O8 | 0.21456 (7) | 0.55655 (10) | 0.17029 (9) | 0.0223 (3) | |
O9 | 0.19702 (7) | 0.68149 (10) | 0.23257 (9) | 0.0229 (4) | |
C8 | 0.20029 (10) | 0.60108 (15) | 0.23140 (13) | 0.0202 (5) | |
C9 | 0.18485 (12) | 0.55366 (17) | 0.30800 (14) | 0.0303 (6) | |
H9A | 0.1954 | 0.5884 | 0.3574 | 0.064 (3)* | |
H9B | 0.2055 | 0.4990 | 0.3118 | 0.064 (3)* | |
H9C | 0.1435 | 0.5427 | 0.3047 | 0.064 (3)* | |
C11 | 0.14968 (11) | 0.86040 (16) | 0.16782 (16) | 0.0282 (6) | |
H11A | 0.1221 | 0.8613 | 0.1184 | 0.053 (3)* | |
H11B | 0.1297 | 0.8360 | 0.2146 | 0.053 (3)* | |
C12 | 0.16665 (11) | 0.95254 (16) | 0.18958 (15) | 0.0273 (5) | |
H12A | 0.1903 | 0.9527 | 0.2429 | 0.053 (3)* | |
H12B | 0.1905 | 0.9751 | 0.1461 | 0.053 (3)* | |
C13 | 0.11608 (13) | 1.01168 (18) | 0.1972 (2) | 0.0445 (8) | |
H13A | 0.0944 | 0.9926 | 0.2445 | 0.053 (3)* | |
H13B | 0.0903 | 1.0072 | 0.1459 | 0.053 (3)* | |
C14 | 0.13350 (16) | 1.10523 (19) | 0.2104 (2) | 0.0563 (10) | |
H14A | 0.1584 | 1.1103 | 0.2616 | 0.053 (3)* | |
H14B | 0.0992 | 1.1404 | 0.2151 | 0.053 (3)* | |
H14C | 0.1541 | 1.1250 | 0.1630 | 0.053 (3)* | |
C21 | 0.41783 (11) | 0.70950 (17) | 0.07025 (15) | 0.0288 (6) | |
H21A | 0.4323 | 0.6962 | 0.1281 | 0.110 (5)* | |
H21B | 0.4067 | 0.6546 | 0.0427 | 0.110 (5)* | |
C22 | 0.46616 (13) | 0.7496 (2) | 0.0248 (2) | 0.0513 (9) | |
H22A | 0.4788 | 0.8029 | 0.0540 | 0.110 (5)* | |
H22B | 0.4513 | 0.7655 | −0.0322 | 0.110 (5)* | |
C23 | 0.51778 (14) | 0.6905 (2) | 0.0190 (3) | 0.0629 (10) | |
H23A | 0.5495 | 0.7237 | −0.0030 | 0.110 (5)* | |
H23B | 0.5306 | 0.6707 | 0.0756 | 0.110 (5)* | |
C24 | 0.50580 (17) | 0.6140 (3) | −0.0354 (3) | 0.0911 (16) | |
H24A | 0.4739 | 0.5814 | −0.0149 | 0.110 (5)* | |
H24B | 0.5399 | 0.5775 | −0.0343 | 0.110 (5)* | |
H24C | 0.4958 | 0.6329 | −0.0926 | 0.110 (5)* | |
C31 | 0.30603 (10) | 0.50768 (13) | 0.04935 (14) | 0.0229 (5) | 0.90 |
H31A | 0.3264 | 0.5160 | −0.0019 | 0.050 (3)* | 0.90 |
H31B | 0.3336 | 0.5200 | 0.0973 | 0.050 (3)* | 0.90 |
C32 | 0.28870 (13) | 0.41416 (12) | 0.05386 (19) | 0.0290 (7) | 0.90 |
H32A | 0.2640 | 0.3994 | 0.0035 | 0.050 (3)* | 0.90 |
H32B | 0.2660 | 0.4056 | 0.1029 | 0.050 (3)* | 0.90 |
C33 | 0.33987 (14) | 0.35436 (16) | 0.0603 (2) | 0.0412 (9) | 0.90 |
H33A | 0.3609 | 0.3601 | 0.0093 | 0.050 (3)* | 0.90 |
H33B | 0.3660 | 0.3722 | 0.1081 | 0.050 (3)* | 0.90 |
C34 | 0.32403 (17) | 0.26092 (18) | 0.0712 (2) | 0.0549 (10) | 0.90 |
H34A | 0.3020 | 0.2548 | 0.1205 | 0.050 (3)* | 0.90 |
H34B | 0.3590 | 0.2263 | 0.0783 | 0.050 (3)* | 0.90 |
H34C | 0.3009 | 0.2412 | 0.0218 | 0.050 (3)* | 0.90 |
C35 | 0.30603 (10) | 0.50768 (13) | 0.04935 (14) | 0.0229 (5) | 0.10 |
H35A | 0.3353 | 0.5282 | 0.0125 | 0.050 (3)* | 0.10 |
H35B | 0.3244 | 0.5028 | 0.1064 | 0.050 (3)* | 0.10 |
C36 | 0.2853 (11) | 0.4198 (7) | 0.0203 (18) | 0.0290 (7) | 0.10 |
H36A | 0.2532 | 0.4033 | 0.0540 | 0.050 (3)* | 0.10 |
H36B | 0.2695 | 0.4254 | −0.0381 | 0.050 (3)* | 0.10 |
C37 | 0.3279 (15) | 0.346 (2) | 0.0239 (18) | 0.0412 (9) | 0.10 |
H37A | 0.3591 | 0.3610 | −0.0122 | 0.050 (3)* | 0.10 |
H37B | 0.3084 | 0.2947 | 0.0002 | 0.050 (3)* | 0.10 |
C38 | 0.3546 (15) | 0.324 (2) | 0.1096 (16) | 0.0549 (10) | 0.10 |
H38A | 0.3673 | 0.3767 | 0.1386 | 0.050 (3)* | 0.10 |
H38B | 0.3875 | 0.2862 | 0.1040 | 0.050 (3)* | 0.10 |
H38C | 0.3263 | 0.2948 | 0.1416 | 0.050 (3)* | 0.10 |
C41 | 0.5000 | −0.0820 (4) | 0.2500 | 0.100 (2) | |
H41A | 0.4606 | −0.1030 | 0.2518 | 0.150* | 0.50 |
H41B | 0.5231 | −0.1030 | 0.2989 | 0.150* | 0.50 |
H41C | 0.5163 | −0.1030 | 0.1993 | 0.150* | 0.50 |
C42 | 0.5000 | 0.0141 (4) | 0.2500 | 0.0587 (14) | |
C43 | 0.54010 (18) | 0.0576 (4) | 0.2095 (3) | 0.0852 (15) | |
H43 | 0.5679 | 0.0270 | 0.1809 | 0.102* | |
C44 | 0.5404 (3) | 0.1462 (5) | 0.2097 (5) | 0.152 (4) | |
H44 | 0.5686 | 0.1767 | 0.1820 | 0.182* | |
C45 | 0.5000 | 0.1894 (7) | 0.2500 | 0.192 (8) | |
H45 | 0.5000 | 0.2504 | 0.2500 | 0.230* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Sn1 | 0.01857 (9) | 0.01607 (9) | 0.01429 (7) | 0.00037 (6) | 0.00206 (6) | −0.00086 (5) |
Sn2 | 0.01640 (9) | 0.01663 (9) | 0.01515 (7) | 0.00063 (6) | −0.00022 (5) | 0.00075 (5) |
Sn3 | 0.01802 (9) | 0.01440 (8) | 0.01468 (7) | 0.00077 (6) | 0.00034 (5) | 0.00074 (5) |
O1 | 0.0203 (8) | 0.0183 (8) | 0.0139 (7) | 0.0016 (7) | 0.0006 (6) | 0.0007 (6) |
O2 | 0.0191 (9) | 0.0152 (8) | 0.0174 (7) | −0.0001 (6) | 0.0011 (6) | 0.0006 (6) |
O3 | 0.0183 (8) | 0.0176 (8) | 0.0153 (7) | 0.0017 (7) | 0.0011 (6) | −0.0001 (6) |
O4 | 0.0257 (10) | 0.0258 (9) | 0.0170 (8) | −0.0023 (7) | 0.0014 (6) | −0.0034 (6) |
O5 | 0.0232 (9) | 0.0251 (9) | 0.0182 (8) | −0.0016 (7) | −0.0017 (6) | −0.0006 (6) |
C4 | 0.0278 (15) | 0.0144 (12) | 0.0197 (11) | 0.0004 (10) | −0.0025 (9) | 0.0003 (8) |
C5 | 0.0328 (15) | 0.0413 (16) | 0.0180 (11) | −0.0001 (13) | −0.0033 (10) | −0.0061 (10) |
O6 | 0.0219 (9) | 0.0190 (9) | 0.0224 (8) | −0.0017 (7) | −0.0022 (6) | 0.0021 (6) |
O7 | 0.0201 (9) | 0.0190 (9) | 0.0215 (8) | −0.0008 (7) | −0.0026 (6) | 0.0011 (6) |
C6 | 0.0226 (13) | 0.0199 (13) | 0.0160 (10) | −0.0010 (10) | 0.0050 (9) | −0.0032 (8) |
C7 | 0.0275 (14) | 0.0239 (14) | 0.0308 (13) | −0.0069 (11) | −0.0017 (10) | 0.0029 (10) |
O8 | 0.0306 (9) | 0.0197 (9) | 0.0168 (7) | −0.0008 (7) | 0.0029 (6) | 0.0020 (6) |
O9 | 0.0318 (10) | 0.0205 (9) | 0.0170 (8) | −0.0015 (7) | 0.0063 (6) | 0.0001 (6) |
C8 | 0.0182 (12) | 0.0245 (14) | 0.0178 (11) | −0.0024 (10) | 0.0013 (8) | 0.0020 (9) |
C9 | 0.0407 (16) | 0.0284 (14) | 0.0227 (12) | −0.0011 (12) | 0.0077 (10) | 0.0058 (10) |
C11 | 0.0246 (14) | 0.0245 (14) | 0.0358 (14) | 0.0031 (11) | 0.0037 (10) | −0.0072 (10) |
C12 | 0.0314 (15) | 0.0227 (13) | 0.0275 (12) | 0.0040 (11) | −0.0004 (10) | −0.0052 (10) |
C13 | 0.0445 (19) | 0.0307 (17) | 0.0562 (19) | 0.0132 (14) | −0.0109 (14) | −0.0158 (13) |
C14 | 0.079 (3) | 0.0328 (18) | 0.054 (2) | 0.0212 (17) | −0.0220 (18) | −0.0145 (14) |
C21 | 0.0253 (14) | 0.0320 (15) | 0.0292 (13) | 0.0101 (11) | 0.0033 (10) | 0.0035 (10) |
C22 | 0.0278 (17) | 0.0427 (19) | 0.086 (2) | 0.0041 (14) | 0.0221 (16) | −0.0081 (17) |
C23 | 0.0265 (18) | 0.061 (2) | 0.103 (3) | 0.0036 (16) | 0.0147 (18) | −0.023 (2) |
C24 | 0.043 (2) | 0.077 (3) | 0.155 (5) | 0.006 (2) | 0.027 (3) | −0.050 (3) |
C31 | 0.0211 (13) | 0.0236 (13) | 0.0239 (11) | 0.0047 (10) | 0.0001 (9) | 0.0029 (9) |
C32 | 0.0305 (16) | 0.0216 (15) | 0.0356 (17) | 0.0049 (12) | 0.0078 (14) | 0.0064 (12) |
C33 | 0.038 (2) | 0.0326 (18) | 0.055 (2) | 0.0124 (16) | 0.0152 (18) | 0.0107 (18) |
C34 | 0.076 (3) | 0.033 (2) | 0.059 (2) | 0.0217 (19) | 0.030 (2) | 0.0140 (16) |
C35 | 0.0211 (13) | 0.0236 (13) | 0.0239 (11) | 0.0047 (10) | 0.0001 (9) | 0.0029 (9) |
C36 | 0.0305 (16) | 0.0216 (15) | 0.0356 (17) | 0.0049 (12) | 0.0078 (14) | 0.0064 (12) |
C37 | 0.038 (2) | 0.0326 (18) | 0.055 (2) | 0.0124 (16) | 0.0152 (18) | 0.0107 (18) |
C38 | 0.076 (3) | 0.033 (2) | 0.059 (2) | 0.0217 (19) | 0.030 (2) | 0.0140 (16) |
C41 | 0.057 (4) | 0.095 (6) | 0.143 (7) | 0.000 | −0.031 (4) | 0.000 |
C42 | 0.041 (3) | 0.085 (4) | 0.046 (3) | 0.000 | −0.018 (2) | 0.000 |
C43 | 0.050 (3) | 0.138 (5) | 0.064 (3) | −0.024 (3) | −0.0227 (19) | 0.014 (3) |
C44 | 0.103 (6) | 0.153 (8) | 0.184 (7) | −0.064 (5) | −0.090 (5) | 0.086 (6) |
C45 | 0.141 (12) | 0.086 (8) | 0.32 (2) | 0.000 | −0.161 (13) | 0.000 |
Sn1—O1 | 2.0969 (15) | C14—H14A | 0.9800 |
Sn1—O2 | 2.0800 (15) | C14—H14B | 0.9800 |
Sn1—O3 | 2.0957 (15) | C14—H14C | 0.9800 |
Sn1—O4 | 2.1614 (15) | C21—C22 | 1.523 (4) |
Sn1—O9 | 2.1665 (15) | C21—H21A | 0.9900 |
Sn1—C11 | 2.129 (2) | C21—H21B | 0.9900 |
Sn2—O1 | 2.0903 (15) | C22—C23 | 1.527 (4) |
Sn2—O2 | 2.0843 (15) | C22—H22A | 0.9900 |
Sn2—O3i | 2.0882 (14) | C22—H22B | 0.9900 |
Sn2—O5 | 2.1606 (15) | C23—C24 | 1.494 (5) |
Sn2—O6 | 2.1715 (15) | C23—H23A | 0.9900 |
Sn2—C21 | 2.129 (2) | C23—H23B | 0.9900 |
Sn3—O1i | 2.0845 (14) | C24—H24A | 0.9800 |
Sn3—O2 | 2.0909 (15) | C24—H24B | 0.9800 |
Sn3—O3 | 2.0885 (15) | C24—H24C | 0.9800 |
Sn3—O7i | 2.1724 (15) | C31—C32 | 1.516 (2) |
Sn3—O8 | 2.1697 (14) | C31—H31A | 0.9900 |
Sn3—C31 | 2.125 (2) | C31—H31B | 0.9900 |
O1—Sn3i | 2.0845 (14) | C32—C33 | 1.516 (2) |
O3—Sn2i | 2.0882 (14) | C32—H32A | 0.9900 |
O4—C4 | 1.260 (3) | C32—H32B | 0.9900 |
O5—C4 | 1.267 (3) | C33—C34 | 1.516 (2) |
C4—C5 | 1.501 (3) | C33—H33A | 0.9900 |
C5—H5A | 0.9800 | C33—H33B | 0.9900 |
C5—H5B | 0.9800 | C34—H34A | 0.9800 |
C5—H5C | 0.9800 | C34—H34B | 0.9800 |
O6—C6 | 1.259 (3) | C34—H34C | 0.9800 |
O7—C6 | 1.266 (3) | C36—C37 | 1.516 (2) |
O7—Sn3i | 2.1724 (15) | C36—H36A | 0.9900 |
C6—C7 | 1.501 (3) | C36—H36B | 0.9900 |
C7—H7A | 0.9800 | C37—C38 | 1.516 (2) |
C7—H7B | 0.9800 | C37—H37A | 0.9900 |
C7—H7C | 0.9800 | C37—H37B | 0.9900 |
O8—C8 | 1.267 (3) | C38—H38A | 0.9800 |
O9—C8 | 1.256 (3) | C38—H38B | 0.9800 |
C8—C9 | 1.503 (3) | C38—H38C | 0.9800 |
C9—H9A | 0.9800 | C41—C42 | 1.498 (8) |
C9—H9B | 0.9800 | C41—H41A | 0.9800 |
C9—H9C | 0.9800 | C41—H41B | 0.9800 |
C11—C12 | 1.524 (3) | C41—H41C | 0.9800 |
C11—H11A | 0.9900 | C42—C43ii | 1.360 (5) |
C11—H11B | 0.9900 | C42—C43 | 1.360 (5) |
C12—C13 | 1.512 (4) | C43—C44 | 1.381 (9) |
C12—H12A | 0.9900 | C43—H43 | 0.9500 |
C12—H12B | 0.9900 | C44—C45 | 1.362 (10) |
C13—C14 | 1.525 (4) | C44—H44 | 0.9500 |
C13—H13A | 0.9900 | C45—C44ii | 1.362 (10) |
C13—H13B | 0.9900 | C45—H45 | 0.9500 |
O2—Sn1—O3 | 77.96 (6) | C13—C12—C11 | 113.6 (2) |
O2—Sn1—O1 | 77.88 (6) | C13—C12—H12A | 108.9 |
O3—Sn1—O1 | 104.78 (6) | C11—C12—H12A | 108.9 |
O2—Sn1—C11 | 177.18 (8) | C13—C12—H12B | 108.9 |
O3—Sn1—C11 | 100.30 (8) | C11—C12—H12B | 108.9 |
O1—Sn1—C11 | 100.53 (8) | H12A—C12—H12B | 107.7 |
O2—Sn1—O4 | 87.87 (6) | C12—C13—C14 | 113.0 (3) |
O3—Sn1—O4 | 159.07 (6) | C12—C13—H13A | 109.0 |
O1—Sn1—O4 | 86.89 (6) | C14—C13—H13A | 109.0 |
C11—Sn1—O4 | 94.39 (8) | C12—C13—H13B | 109.0 |
O2—Sn1—O9 | 87.75 (6) | C14—C13—H13B | 109.0 |
O3—Sn1—O9 | 85.78 (6) | H13A—C13—H13B | 107.8 |
O1—Sn1—O9 | 159.73 (6) | C13—C14—H14A | 109.5 |
C11—Sn1—O9 | 94.36 (8) | C13—C14—H14B | 109.5 |
O4—Sn1—O9 | 78.27 (6) | H14A—C14—H14B | 109.5 |
O2—Sn2—O3i | 104.24 (6) | C13—C14—H14C | 109.5 |
O2—Sn2—O1 | 77.93 (6) | H14A—C14—H14C | 109.5 |
O3i—Sn2—O1 | 78.22 (5) | H14B—C14—H14C | 109.5 |
O2—Sn2—C21 | 99.96 (8) | C22—C21—Sn2 | 114.34 (19) |
O3i—Sn2—C21 | 100.30 (8) | C22—C21—H21A | 108.7 |
O1—Sn2—C21 | 176.96 (8) | Sn2—C21—H21A | 108.7 |
O2—Sn2—O5 | 86.58 (6) | C22—C21—H21B | 108.7 |
O3i—Sn2—O5 | 160.42 (6) | Sn2—C21—H21B | 108.7 |
O1—Sn2—O5 | 88.41 (6) | H21A—C21—H21B | 107.6 |
C21—Sn2—O5 | 93.67 (8) | C21—C22—C23 | 113.6 (3) |
O2—Sn2—O6 | 160.09 (6) | C21—C22—H22A | 108.9 |
O3i—Sn2—O6 | 86.44 (6) | C23—C22—H22A | 108.9 |
O1—Sn2—O6 | 88.13 (6) | C21—C22—H22B | 108.9 |
C21—Sn2—O6 | 94.44 (8) | C23—C22—H22B | 108.9 |
O5—Sn2—O6 | 78.81 (6) | H22A—C22—H22B | 107.7 |
O1i—Sn3—O3 | 78.34 (6) | C24—C23—C22 | 113.5 (3) |
O1i—Sn3—O2 | 103.89 (6) | C24—C23—H23A | 108.9 |
O3—Sn3—O2 | 77.88 (6) | C22—C23—H23A | 108.9 |
O1i—Sn3—C31 | 102.40 (7) | C24—C23—H23B | 108.9 |
O3—Sn3—C31 | 175.48 (7) | C22—C23—H23B | 108.9 |
O2—Sn3—C31 | 97.63 (7) | H23A—C23—H23B | 107.7 |
O1i—Sn3—O8 | 160.23 (6) | C23—C24—H24A | 109.5 |
O3—Sn3—O8 | 88.49 (6) | C23—C24—H24B | 109.5 |
O2—Sn3—O8 | 87.42 (6) | H24A—C24—H24B | 109.5 |
C31—Sn3—O8 | 91.90 (7) | C23—C24—H24C | 109.5 |
O1i—Sn3—O7i | 86.96 (6) | H24A—C24—H24C | 109.5 |
O3—Sn3—O7i | 87.47 (6) | H24B—C24—H24C | 109.5 |
O2—Sn3—O7i | 159.40 (6) | C32—C31—Sn3 | 116.47 (17) |
C31—Sn3—O7i | 97.01 (7) | C32—C31—H31A | 108.2 |
O8—Sn3—O7i | 77.69 (6) | Sn3—C31—H31A | 108.2 |
Sn3i—O1—Sn2 | 100.00 (6) | C32—C31—H31B | 108.2 |
Sn3i—O1—Sn1 | 132.51 (7) | Sn3—C31—H31B | 108.2 |
Sn2—O1—Sn1 | 99.79 (6) | H31A—C31—H31B | 107.3 |
Sn1—O2—Sn2 | 100.55 (6) | C31—C32—C33 | 112.4 (3) |
Sn1—O2—Sn3 | 100.39 (6) | C31—C32—H32A | 109.1 |
Sn2—O2—Sn3 | 133.30 (7) | C33—C32—H32A | 109.1 |
Sn2i—O3—Sn3 | 99.94 (6) | C31—C32—H32B | 109.1 |
Sn2i—O3—Sn1 | 132.08 (7) | C33—C32—H32B | 109.1 |
Sn3—O3—Sn1 | 99.95 (6) | H32A—C32—H32B | 107.9 |
C4—O4—Sn1 | 129.87 (14) | C34—C33—C32 | 113.6 (3) |
C4—O5—Sn2 | 129.71 (15) | C34—C33—H33A | 108.9 |
O4—C4—O5 | 125.6 (2) | C32—C33—H33A | 108.9 |
O4—C4—C5 | 117.3 (2) | C34—C33—H33B | 108.9 |
O5—C4—C5 | 117.0 (2) | C32—C33—H33B | 108.9 |
C4—C5—H5A | 109.5 | H33A—C33—H33B | 107.7 |
C4—C5—H5B | 109.5 | C37—C36—H36A | 107.8 |
H5A—C5—H5B | 109.5 | C37—C36—H36B | 107.8 |
C4—C5—H5C | 109.5 | H36A—C36—H36B | 107.1 |
H5A—C5—H5C | 109.5 | C36—C37—C38 | 116 (3) |
H5B—C5—H5C | 109.5 | C36—C37—H37A | 108.3 |
C6—O6—Sn2 | 129.60 (15) | C38—C37—H37A | 108.3 |
C6—O7—Sn3i | 129.45 (14) | C36—C37—H37B | 108.3 |
O6—C6—O7 | 126.0 (2) | C38—C37—H37B | 108.3 |
O6—C6—C7 | 116.8 (2) | H37A—C37—H37B | 107.4 |
O7—C6—C7 | 117.2 (2) | C37—C38—H38A | 109.5 |
C6—C7—H7A | 109.5 | C37—C38—H38B | 109.5 |
C6—C7—H7B | 109.5 | H38A—C38—H38B | 109.5 |
H7A—C7—H7B | 109.5 | C37—C38—H38C | 109.5 |
C6—C7—H7C | 109.5 | H38A—C38—H38C | 109.5 |
H7A—C7—H7C | 109.5 | H38B—C38—H38C | 109.5 |
H7B—C7—H7C | 109.5 | C42—C41—H41A | 109.5 |
C8—O8—Sn3 | 128.85 (14) | C42—C41—H41B | 109.5 |
C8—O9—Sn1 | 131.40 (14) | H41A—C41—H41B | 109.5 |
O9—C8—O8 | 125.3 (2) | C42—C41—H41C | 109.5 |
O9—C8—C9 | 117.4 (2) | H41A—C41—H41C | 109.5 |
O8—C8—C9 | 117.3 (2) | H41B—C41—H41C | 109.5 |
C8—C9—H9A | 109.5 | C43ii—C42—C43 | 120.3 (7) |
C8—C9—H9B | 109.5 | C43ii—C42—C41 | 119.9 (3) |
H9A—C9—H9B | 109.5 | C43—C42—C41 | 119.9 (3) |
C8—C9—H9C | 109.5 | C42—C43—C44 | 120.0 (6) |
H9A—C9—H9C | 109.5 | C42—C43—H43 | 120.0 |
H9B—C9—H9C | 109.5 | C44—C43—H43 | 120.0 |
C12—C11—Sn1 | 115.28 (17) | C45—C44—C43 | 119.5 (9) |
C12—C11—H11A | 108.5 | C45—C44—H44 | 120.2 |
Sn1—C11—H11A | 108.5 | C43—C44—H44 | 120.2 |
C12—C11—H11B | 108.5 | C44ii—C45—C44 | 120.7 (12) |
Sn1—C11—H11B | 108.5 | C44ii—C45—H45 | 119.7 |
H11A—C11—H11B | 107.5 | C44—C45—H45 | 119.7 |
Sn2—O2—Sn3—O1i | −25.88 (11) | O1i—Sn1i—O3i—Sn2 | 24.53 (11) |
O2—Sn3—O1i—Sn1i | 24.87 (11) | Sn1i—O3i—Sn2—O2 | −24.89 (11) |
Sn3—O1i—Sn1i—O3i | −24.64 (11) | O3i—Sn2—O2—Sn3 | 25.96 (11) |
Symmetry codes: (i) −x+1/2, −y+3/2, −z; (ii) −x+1, y, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [Sn6(C4H9)6(C2H3O2)6O6]·C7H8 |
Mr | 1597.21 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 150 |
a, b, c (Å) | 23.4154 (8), 15.5832 (6), 16.1012 (6) |
β (°) | 93.926 (2) |
V (Å3) | 5861.3 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 2.58 |
Crystal size (mm) | 0.30 × 0.22 × 0.10 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.509, 0.783 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 76854, 6788, 5890 |
Rint | 0.035 |
(sin θ/λ)max (Å−1) | 0.661 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.020, 0.046, 1.05 |
No. of reflections | 6788 |
No. of parameters | 325 |
No. of restraints | 6 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.65, −0.61 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2006), SHELXTL (Sheldrick, 2008).
Sn2—O2—Sn3—O1i | −25.88 (11) | O1i—Sn1i—O3i—Sn2 | 24.53 (11) |
O2—Sn3—O1i—Sn1i | 24.87 (11) | Sn1i—O3i—Sn2—O2 | −24.89 (11) |
Sn3—O1i—Sn1i—O3i | −24.64 (11) | O3i—Sn2—O2—Sn3 | 25.96 (11) |
Symmetry code: (i) −x+1/2, −y+3/2, −z. |
References
Beckmann, J., Dakternieks, D., Duthie, A., Thompson, L. & Tiekink, E. R. T. (2004). Acta Cryst. E60, m767–m768. Web of Science CSD CrossRef IUCr Journals Google Scholar
Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2009). APEX2 (including SAINT) and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Buslaev, Y. A., Kravchenko, E. A., Burtzev, M. Y. & Aslanov, L. A. (1989). Coord. Chem. Rev. 93, 185–204. CrossRef CAS Web of Science Google Scholar
Day, R. O., Chandrasekhar, V., Kumara Swamy, K. C., Burton, S. D. & Holmes, R. R. (1988). Inorg. Chem. 27, 2887–2893. CSD CrossRef CAS Web of Science Google Scholar
Kuan, F. S., Dakternieks, D. & Tiekink, E. R. T. (2002). Acta Cryst. E58, m301–m303. Web of Science CSD CrossRef IUCr Journals Google Scholar
Mehrotra, R. C. & Bohra, R. (1983). In Metal Carboxylates. London, New York: Academic Press. Google Scholar
Reuter, H. & Puff, H. (1992). J. Organomet. Chem. 424, 23–31. CSD CrossRef CAS Web of Science Google Scholar
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The synthesis of organotin(IV) carboxylates is well established since a long time (Mehrotra & Bohra, 1983) and many of their crystal structures have been investigated into detail (Tiekink, 1991). Thus, in the case of triorganotin moieties R3Sn the corresponding carboxylates are of general formula R3Sn(O2CR') with (O2CR') representing the carboxylate ion. Diorganotin oxides, R2SnO, most often insoluble in indifferent organic solvents, can be easily dissolved in a large number of carboxylic acids, R'COOH, giving rise to the formation of carboxylates with a lot of different compositions and a tremendous diversity of molecular structures. Applying the same conditions to monoorganotin sesquioxides, RSnO1,5, also insoluble in non-complexing organic solvents results in the formation of monoorganooxotin carboxylates with "ladder"-type structures of composition (RSn)6O4(O2CR')10 (Day et al.,1988) or, more frequently, to hexanuclear compounds [RSnO(O2CR')]6. In the latter case, the structure is dominated by a hexagonal prismatic or "drum"-like arrangement of the tin-oxygen core as was demonstrated in the case of acetates (R' = CH3) for R = iPr (Kuan et al., 2002), R = tmsm (Beckmann et al., 2004), and R = Me (Day et al.,1988). By dissolving n-butylstannonic acid of idealized formula nBuSnO(OH) in a mixture of toluene/acetic acid and removing the resulting water by use of a Dean-Stark apparatus we were able to obtain single crystals of the corresponding R = n-butyl hexamer as the 1:1 toluene solvate, [nBuSnO(OAc)]6 x C7H8.
The asymmetric unit of the title compound consists of a centrosymmetric hexamer (Fig. 1) with i at (1/4,3/4,0) and a toluene molecule of site symmetry 2. As usual for the constitution (Fig. 2) of the drum, the six-membered tin-oxygen rings forming the bases are not planar but adopt a flat chair-conformation with the torsion angles listed in Tab. 1. Both rings are rotated through 60° against each other so that each oxygen atom bonds to a tin atom of the adjacent ring. The six sides of the drum consist of tin oxygen trapezoids with small angles at tin [77.88 (6)° - 78.34 (6)°, mean value 78.0 (2)°] and larger ones at oxygen [99.79 (6)° - 100.55 (6)°, mean value 100.1 (3)°]. These four-membered rings are also non-planar but bent [18.19 (5)°-18.99 (4)°] along the O···O diagonals that are 2.625 (2) - 2.636 (2) Å long in contrast to the Sn··· Sn diagonals that are much more longer [3.1980 (2) - 3.2041 (2) Å]. Both tin atoms of these six four-membered tin oxygen rings are bridged by acetate groups with carbon oxygen distances that are almost equal [1.256 (3) - 1.267 (3) Å, mean value 1.263 (5) Å] indicating their symmetrical coordination mode (Fig. 3).
In summary, all tin atoms are octahedrally coordinated by the n-butyl ligand, three oxygen atoms of the drum and two oxygen atoms of two different acetate groups (Fig. 2). The distortions of the octahedra can be described by carbon-tin-oxygen axes that are slightly bent [175.48 (7)° - 177.18 (8)°], and bond angles of the organic groups to their cis-oriented neighboring oxygen atoms that are considerably widened [91.90 (7)° - 100.53 (8)°].
While the tin-carbon bonds are very similar [2.125 (2) to 2.129 (2) Å, mean value: 2.128 (2) Å] tin-oxygen bond lengths fall into two clearly different groups. The longer ones [2.162 (2) - 2.172 (2) Å, mean value: 2.167 (5) Å] are those to the bridging acetate groups. The narrow range is in correspondence with the narrow range of carbon oxygen bonds, described above, indicating a symmetrical bonding of the acetate groups. The shorter ones [2.080 (2) - 2.097 (2) Å] arise from the µ3-oxygen atoms within the drum. They can be subdivided into those that are trans to the organic ligand and significantly shorter [2.080 (2) - 2.085 (2) Å, mean value: 2.083 (3) Å] and those that are somewhat longer arising from the corresponding cis-oriented oxygen atoms [2.0882 (2) - 2.0969 (2) Å, mean value: 2.092 (4) Å]. This strengthening although less marked is similar to the static trans-strengthening observed in the case of alkyl tin halides (Buslaev et al., 1989), Reuter & Puff, 1992).
Intermolecular interactions of the cylindrical hexamers are limited to van-der-Waals ones because the accessibility of the polar tin-oxygen core is restricted (Fig. 4). As a result of these weak interactions, molecules are arranged in planar hexagonal nets (Fig. 5a) with two different orientations of the drum (Fig. 5b). Between these nets large apolar channels with large cavities exist (Fig. 6a) which partially are fulfilled by the solvent molecules (Fig. 6b).