Novel 10- and 20-membered tin- and silicon-containing rings: Synthesis, complexation behavior, and conversion into a lewis acidic polymer

Article abstract of DOI:10.1021/om020740b

Reaction of the dimethylsilylmethyl-substituted tetraorganotin derivative CH₂[CH₂Sn(Ph₂)CH₂Si(H)Me₂ ]₂ (1) and CH₂[CH₂Sn(Ph₂)CH₂Si(i-PrO)Me₂ ]₂ (3), respectively, with mercuric chloride afforded the novel silicon- and tin-containing 10- and 20-membered rings cyclo-CH₂[CH₂Sn(Cl₂)CH₂Si(Me₂ )]₂O (4) and cyclo-CH₂[CH₂Sn(Cl₂)CH₂Si(Me₂ )OSi(Me₂)CH₂Sn(Cl₂)CH₂]₂ CH₂ (5). Both compounds 4 and 5 can be converted into the soluble Lewis acidic polymer poly-[Si(Me₂)CH₂Sn(Cl₂)(CH₂)₃ Sn(Cl₂)CH₂Si(Me₂)O] (8). ¹¹⁹Sn NMR studies indicate that 4 acts as a bidentate Lewis acid toward chloride ions, exclusively forming the 1:1 complex [cyclo-CH₂[CH₂Sn(Cl₂)CH₂Si(Me₂ )]₂O·Cl]-[(Ph₃P)₂N]⁺ (7). The molecular structures as determined by single-crystal X-ray diffraction analysis of 4 and 7 are reported.

Full text of DOI:10.1021/om020740b

328
Organometallics 2003, 22, 328-336
Novel 10- a n d 20-Mem ber ed Tin - a n d Silicon -Con ta in in g
Rin gs: Syn th esis, Com p lexa tion Beh a vior , a n d
Con ver sion in to a Lew is Acid ic P olym er †,‡
Marcus Schulte, Giuseppina Gabriele, Markus Schu¨rmann, and
Klaus J urkschat*
Lehrstuhl fu¨r Anorganische Chemie II, Fachbereich Chemie der Universita¨t Dortmund,
D-44221 Dortmund, Germany
Andrew Duthie and Dainis Dakternieks*
Centre for Chiral and Molecular Technologies, Deakin University,
Geelong, Victoria 3217, Australia
Received September 9, 2002
Reaction of the dimethylsilylmethyl-substituted tetraorganotin derivative CH2[CH2Sn-
(Ph2)CH2Si(H)Me2]2 (1) and CH2[CH2Sn(Ph2)CH2Si(i-PrO)Me2]2 (3), respectively, with
mercuric chloride afforded the novel silicon- and tin-containing 10- and 20-membered rings
cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) and cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)OSi(Me2)CH2-
Sn(Cl2)CH2]2CH2 (5). Both compounds 4 and 5 can be converted into the soluble Lewis acidic
polymer poly-[Si(Me2)CH2Sn(Cl2)(CH2)3Sn(Cl2)CH2Si(Me2)O] (8). 119Sn NMR studies indicate
that 4 acts as a bidentate Lewis acid toward chloride ions, exclusively forming the 1:1 complex
[cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O‚Cl]-[(Ph3P)2N]+ (7). The molecular structures as de-
termined by single-crystal X-ray diffraction analysis of 4 and 7 are reported.
In tr od u ction
Our interest in this area has mainly focused on the
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such as B,2 Al,3a,b Ga,3c In,4 Si,5 Ge,6 Sn,7 and Hg.8
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† Dedicated to Prof. H.-P. Abicht on the occasion of his 60th birthday.
‡ This paper contains part of the Ph.D. thesis of M. Schulte,
Universita¨t Dortmund, 2000. Part of this work was first presented at
the Xth International Conference on the Coordination and Organo-
metallic Chemistry of Germanium, Tin, and Lead, J uly 8-12, 2001,
Bordeaux, France, Book of Abstracts IL9, and at the 222nd ACS
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10.1021/om020740b CCC: $25.00 © 2003 American Chemical Society
Publication on Web 12/14/2002

Tin- and Silicon-Containing Rings
Organometallics, Vol. 22, No. 2, 2003 329
cyclic organotin-based7d,e,k-r,v Lewis acids, and, more
recently, tin- as well as silicon-containing rings7s-u have
been included in these studies. An interesting aspect of
our investigations is the observation7ï,v that bis(phe-
nyldichlorostannyl)methane, CH2[Sn(Cl2)Ph]2,9 when
incorporated into a polyethylene matrix, exhibits a
remarkably high selectivity toward dihydrogen phos-
phate. However, the ion-sensitive electrode based on this
organotin compound showed a rather short lifetime, due
to leaching of the carrier from the membrane. One
possible strategy to overcome this shortcoming is the
incorporation of the Sn(Cl2)CH2Sn(Cl2) fragment into a
polymer. In earlier work we synthesized the eight-
membered rings cyclo-CH2[Sn(Cl2)CH2Si(Me2)]2O7u and
cyclo-CH2[Sn(Ph2)CH2Si(Me2)]2O7u but failed to achieve
their ring-opening polymerization. In continuation of
this earlier work we now report the synthesis of the 10-
and 20-membered rings cyclo-CH2[CH2Sn(Cl2)CH2Si-
(Me2)]2O and cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)OSi(Me2)-
CH2Sn(Cl2)CH2]2CH2, respectively, and explore their
potential to undergo ring-opening polymerization.
Ch a r t 1
81.9 (total integral approximately 15% of the major
signals). The 29Si NMR spectrum of the same sample
displayed signals at δ 12.3 (2J (29Si-117/119Sn) ) 36 Hz)
(signal c), 10.4 (2J (29Si-117/119Sn) ) 31 Hz) (signal d),
9.2, 8.6, 8.3, and -3.2. On the basis of coupling data,
the signals (a) and (c) are assigned to the 10-membered
ring cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) and the
signals (b) and (d) to the 20-membered ring cyclo-
CH2[CH2Sn(Cl2)CH2Si(Me2)OSi(Me2)CH2Sn(Cl2)CH2]2-
CH2 (5). No assignment was made for the other minor
intense signals.
Compounds 4 and 5 were isolated from the reaction
mixture in moderate yield by combination of fractional
crystallization and size exclusion chromatography. The
10-membered ring 4 is a colorless crystalline solid that
is soluble in dichloromethane, chloroform, diethyl ether,
and thf, but almost insoluble in n-hexane. The 20-
membered ring 5 is a colorless amorphous solid that is
soluble in acetone, less soluble in dichloromethane and
chloroform, and almost insoluble in diethyl ether and
n-hexane.
Resu lts a n d Discu ssion
The reaction of 1,3-bis(diphenylfluorostannyl)pro-
pane,10 CH2[CH2Sn(F)Ph2]2, and bis(diphenylfluorostan-
nyl)methane,7p CH2[Sn(F)Ph2]2, with 2 molar equiv of
the Grignard reagent Me2(H)SiCH2MgCl11 provided the
organosilylmethyl-substituted organotin compounds
CH2[CH2Sn(Ph2)CH2Si(H)Me2]2 (1) and CH2[Sn(Ph2)CH2-
Si(H)Me2]2 (2), respectively (eq 1). The reaction of
CH2[CH2Sn(F)Ph2]2 with 2 molar equiv of the Grignard
reagent Me2(i-PrO)SiCH2MgCl12 gave the corresponding
organotin derivative CH2[CH2Sn(Ph2)CH2Si(i-PrO)Me2]2
(3) (eq 1). Compounds 1-3 are colorless oils that were
obtained in almost quantitative yield.
Both the 10- and 20-membered rings 4 and 5 have
been characterized by standard analytical methods such
as elemental analysis, multinuclear NMR spectroscopy
(see Experimental Section), and single-crystal X-ray
analysis (compound 4, see below). The identity of the
10- and 20-membered ring structures in solution has
been further confirmed by molecular weight measure-
ments (see Experimental Section) and electrospray mass
spectrometry (ESMS). Thus, the negative ion electro-
spray mass spectrum of a solution of compound 4 in
acetonitrile exhibits the four major isotopic cluster
patterns shown in Chart 1, and the spectrum taken from
compound 5 under the same conditions shows an
isotopic cluster pattern centered at m/z ) 1199, which
corresponds to [5‚Cl]-.
Notably, the ESMS spectrum of the 10-membered ring
cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) also shows iso-
topic cluster patterns corresponding to ionized dimers
and trimers of 4, a possible hint at the ability of 4 to
undergo ring-opening polymerization (see below).
Although no detailed studies concerning the mecha-
nism for the formation of compounds 4 and 5 have been
performed, the following reaction sequence appears
plausible. In the first step, mercuric chloride cleaves the
tin-phenyl bonds to give the diorganotin dichloro
Treatment of CH2[CH2Sn(Ph2)CH2Si(H)Me2]2 (1) with
4 molar equiv of mercuric chloride in acetone gave a
crude reaction product, the 119Sn NMR spectrum (CDCl3)
of which showed two major signals at δ 115.9 (signal a)
and 110.2 (signal b) with an integral ratio of about 1:1
and four minor resonances at δ 118.2, 114.8, 107.5, and
(8) (a) Tschinkl, M.; Schier, A.; Riede, J .; Gabba¨ı, F. P. Organome-
tallics 1999, 18, 1747. (b) Tschinkl, M.; Schier, A.; Riede, J .; Gabba¨ı,
F. P. Organometallics 1999, 18, 2040. (c) Wuest, J . D.; Zacharie, B.
Organometallics 1985, 4, 410. (d) Beauchamp, A. L.; Olivier, M. J .;
Wuest, J . D.; Zacharie, B. J . Am. Chem. Soc. 1986, 108, 73. (e)
Beauchamp, A. L.; Olivier, M. J .; Wuest, J . D.; Zacharie, B. Organo-
metallics 1987, 6, 153. (f) Wuest, J . D.; Zacharie, B. J . Am. Chem. Soc.
1987, 109, 4714. (g) Vaugeois, J .; Simard, M.; Wuest, J . D. Organo-
metallics 1998, 17, 1215.
(9) Dakternieks, D.; J urkschat, K.; Wu, H.; Tiekink, E. R. T.
Organometallics 1993, 12, 2788.
(10) Mehring, M.; Schu¨rmann, M.; Paulus, I.; Horn, D.; J urkschat,
K.; Orita, A.; Otera, J .; Dakternieks, D.; Duthie, A. J . Organomet.
Chem. 1999, 574, 176.
(11) J arvie, A. W. P.; Rowley, R. J . J . Organomet. Chem. 1972, 34,
C7.
(12) Dow Corning Corp., US Patent, 1959.

330 Organometallics, Vol. 22, No. 2, 2003
Schulte et al.
Sch em e 1
to give the diorganotin dichloro derivative CH2[CH2Sn-
(Cl2)CH2Si(i-PrO)Me2]2 (3a ), which subsequently un-
dergoes diorganotin dichloride-catalyzed hydrolysis of
the isopropoxysilyl groups and condensation of the
resulting silanol functionalities to give cyclo-CH2[CH2-
Sn(Cl2)CH2Si(Me2)]2O (4). In addition to the signals
assigned to compound 4, the 29Si and 119Sn NMR spectra
(CH2Cl2) of the crude reaction mixture according to eq
2 showed further resonances in the regions δ 10-7 and
111-105, which are likely to belong to the 20-membered
ring 5 and higher oligomers. No attempts were made
to isolate the 20-membered ring 5 from this reaction
mixture.
Furthermore, the previously reported eight-membered
ring cyclo-CH2[Sn(Cl2)CH2SiMe2]2O (6)7u has also been
prepared by reaction of compound 2 with 4 molar equiv
of mercuric chloride (eq 3).
derivative CH2[CH2Sn(Cl2)CH2Si(H)Me2]2 (1a ) and phe-
nylmercury chloride, PhHgCl. Half of the latter reacts
with the silane fuctionalities of 1a to give PhHgH, which
decomposes into benzene and mercury, and CH2[CH2-
Sn(Cl2)CH2Si(Cl)Me2]2 (1b), which, in the presence of
water and remaining PhHgCl, hydrolyzes and condenses
to form the siloxane bridge-containing compounds 4 and
5. This view is supported by the observation (i) that only
HgCl2 and not PhHgCl cleaves two phenyl groups from
a diphenyldiorganostannane and that no tin-phenyl
bond was left in the reaction shown in Scheme 1, (ii)
that PhHgCl is able to cleave the Si-H bond in a
triorganosilane, and (iii) that formation of mercury was
indicated by the gray color of the reaction mixture, and
(iv) that only half of the amount of PhHgCl to be
expected from the first reaction step has been isolated.
Alternatively and similar to the synthesis of the eight-
membered ring cyclo-CH2[Sn(Cl2)CH2SiMe2]2O (6),7u the
10-membered ring cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O
(4) has also been prepared by reaction of the dimethyl-
isopropoxysilylmethyl-substituted tetraorganostannane
derivative 3 with mercuric chloride (eq 2).
The reactions shown in eqs 1-3 and Scheme 1
illustrate the generality of both dimethylsilylmethyl-
and dimethylisopropoxysilylmethyl-substituted organo-
tin derivatives to serve as synthons for convenient one-
pot syntheses of siloxane as well as organotin moiety-
containing rings.
Molecu la r Str u ctu r e of cyclo-CH2[CH2Sn (Cl2)-
CH2Si(Me2)]2O (4). The molecular structure of com-
pound 4 is illustrated in Figure 1. Unit cell data,
refinement details, and selected interatomic parameters
are listed in Tables 1-3.
The unit cell of cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O
(4) contains two centrosymmetric dimers with the
dimerization realized by unsymmetrical intermolecular
Sn(1)-Cl(2)‚‚‚Sn(1a)/Sn(1)‚‚‚Cl(2a)-Sn(1a) bridges. The
coordination geometry at Sn(1) can be best described
as bicapped tetrahedron ([4+2] coordination); that is,
in addition to the Sn(1)-C(1), Sn(1)-C(9), Sn(1)-Cl-
(1), and Sn(1)-Cl(2) bonds with lengths of 2.137(4),
2.105(4), 2.351(1), and 2.381(1) Å being in the typical
range for such bonds there are intramolecular Sn(1)‚‚‚
O(1) and intermolecular Sn(1)‚‚‚Cl(2a) contacts of 3.312-
(2) and 3.441(1) Å, respectively. The two latter distances
are shorter than the sums of the van der Waals radii13
(13) Huheey, J . E.; Keiter, E. A.; Keiter, R. L. In Inorganic
Chemistry-Principles of Structure and Reactivity, 4th ed.; Harper
Collins College Publishers: New York, 1993.
In this reaction no mercury is formed and the first
reaction step involves cleavage of the tin-phenyl bonds

Tin- and Silicon-Containing Rings
Organometallics, Vol. 22, No. 2, 2003 331
Ta ble 2. Selected In ter a tom ic Bon d Dista n ces (Å)
for 4 a n d 7
4
7
Sn(1)-C(9)
Sn(1)-C(1)
Sn(1)-Cl(1)
Sn(1)-Cl(2)
Sn(1)-O(1)
Sn(1)-Cl(2a)
Sn(1)-Cl(5)
Sn(2)-C(4)
Sn(2)-C(3)
Sn(2)-Cl(3)
Sn(2)-Cl(4)
Sn(2)-Cl(5)
Si(1)-O(1)
Si(2)-O(1)
2.105(4)
2.137(4)
2.351(1)
2.381(1)
3.312(2)
3.441(1)
2.120(4)
2.118(5)
2.453(2)
2.362(2)
3.428(3)
2.812(1)
2.108(4)
2.132(4)
2.359(1)
2.505(1)
2.686(1)
1.627(3)
1.622(3)
2.105(4)
2.138(4)
2.355(1)
2.341(1)
1.646(3)
1.642(3)
Ta ble 3. Selected Bon d An gles (d eg) for 4 a n d 7
4
7
C(9)-Sn(1)-C(1)
C(9)-Sn(1)-Cl(1)
C(1)-Sn(1)-Cl(1)
C(9)-Sn(1)-Cl(2)
C(1)-Sn(1)-Cl(2)
Cl(1)-Sn(1)-Cl(2)
C(9)-Sn(1)-O(1)
C(1)-Sn(1)-O(1)
Cl(1)-Sn(1)-O(1)
Cl(2)-Sn(1)-O(1)
C(9)-Sn(1)-Cl(2a)
C(1)-Sn(1)-Cl(2a)
Cl(1)-Sn(1)-Cl(2a)
Cl(2)-Sn(1)-Cl(2a)
O(1)-Sn(1)-Cl(2a)
C(9)-Sn(1)-Cl(5)
C(1)-Sn(1)-Cl(5)
Cl(1)-Sn(1)-Cl(5)
Cl(2)-Sn(1)-Cl(5)
Cl(5)-Sn(1)-O(1)
C(4)-Sn(2)-C(3)
C(4)-Sn(2)-Cl(3)
C(3)-Sn(2)-Cl(3)
C(4)-Sn(2)-Cl(4)
C(3)-Sn(2)-Cl(4)
Cl(3)-Sn(2)-Cl(4)
C(4)-Sn(2)-Cl(5)
C(3)-Sn(2)-Cl(5)
Cl(3)-Sn(2)-Cl(5)
Cl(4)-Sn(2)-Cl(5)
Sn(1)-Cl(5)-Sn(2)
Si(1)-O(1)-Si(2)
Si(1)-C(4)-Sn(2)
Si(2)-C(9)-Sn(1)
134.4(2)
103.5(1)
106.4(1)
106.0(1)
102.4(1)
99.05(5)
57.5(1)
138.2(2)
95.1(1)
93.5(2)
108.5(1)
111.6(2)
94.20(7)
54.5(1)
84.4(2)
111.02(7)
149.64(8)
78.9(1)
114.35(6)
144.96(5)
78.1(1)
F igu r e 1. General view (SHELXTL) of a dimer of mol-
ecules of 4 showing 30% probability displacement ellipsoids
and the atom-numbering scheme (symmetry transforma-
tions used to generate equivalent atoms: -x, -y + 1, -z
+ 1).
73.3(1)
177.59(4)
78.76(4)
67.99(5)
Ta ble 1. Cr ysta llogr a p h ic Da ta for 4 a n d 7
86.9(1)
85.8(1)
4
7
177.66(5)
84.00(5)
71.15(6)
138.0(2)
110.1(1)
111.7(1)
94.0(1)
89.4(1)
90.45(5)
87.4(1)
formula
fw, g/mol
cryst syst
cryst size, mm
space group
a, Å
C9H22Cl4OSi2Sn2
581.63
monoclinic
C
45H52Cl5NOP2Si2Sn2
1155.63
monoclinic
124.0(2)
108.4(1)
108.0(1)
107.0(1)
106.7(1)
100.19(5)
0.30 × 0.15 × 0.15 0.30 × 0.25 × 0.25
P21/c
P21/c
9.202(1)
18.570(1)
12.760(1)
109.197(1)
2059.2(3)
4
1.876
1.864(2)
3.050
9.645(1)
17.596(1)
30.846(1)
96.270(1)
5203.7(6)
4
1.475
1.486(9)
1.357
b, Å
c, Å
â, deg
V, Å3
90.7(1)
Z
F
F
87.40(5)
177.74(4)
109.62(4)
150.0(2)
118.5(2)
114.8(2)
calcd, Mg/m3
meas, Mg/m3
µ, mm-1
138.0(2)
119.7(2)
117.0(2)
F(000)
1120
2320
θ range, deg
4.39 to 25.69
-11 e h e 11
-22 e k e 22
-13 e l e 13
27 698
4.09 to 26.37
-11 e h e 11
-21 e k e 21
-38 e l e 38
63 868
index ranges
der Waals radii of these atoms to both tin atoms occur
with one being longer (3.559(2) Å) and three being
shorter (3.061(2), 3.074(2), 3.184(2) Å) than the Sn(1)‚
‚‚O(1) distance in cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O
(4). Although a number of organotin compounds exhibit-
ing intramolecular Sn‚‚‚O distances between 2.38(4) and
3.067(2) Å have been reported,14 cyclo-CH2[Sn(Cl2)CH2-
Si(Me2)]2O (6)7u and cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O
(4) are the only ones reported so far with the oxygen
donor site bound to silicon. Associated with this in-
tramolecular Sn(1)‚‚‚O(1) distance in the 10-membered
ring 4 is the Si(1)-O(1)-Si(2) angle of 138.0(2)°, which
no. of reflns collcd
completeness to θmax 92.9
no. of indep reflns/
Rint
94.2
10008/0.059
3639/0.029
no. of reflns obsd
with (I > 2σ(I))
no. of refined
params
2976
168
4312
529
GooF (F2)
1.035
0.780
R1(F) (I > 2σ(I))
wR2(F2) (all data)
(∆/ σ)max
0.0283 0.0770
0.0363 0.0732
0.001
0.419/-0.873
0.001
0.503/-0.511
largest diff peak/
hole, e/Å3
(14) (a) Willem, R.; Delmotte, A.; Borger, I. D.; Biesemans, M.;
Gielen, M.; Kayser, F.; Tiekink, E. R. T. J . Organomet. Chem. 1994,
480, 255. (b) Kayser, F.; Biesemans, M.; Delmotte, A.; Verbruggen, I.;
Borger, I. D.; Gielen, M.; Willem, R.; Tiekink, E. R. T. Organometallics
1994, 13, 4026. (c) Kolb, U.; Dra¨ger, M.; J ousseaume, B. Organome-
tallics 1991, 10, 2737. (d) Kolb, U.; Beuter, M.; Dra¨ger, M. Inorg. Chem.
1994, 33, 4522.
of tin (2.20 Å) and oxygen (1.50 Å) and of tin and
chlorine (1.70 Å), respectively. In the related eight-
membered ring cyclo-CH2[Sn(Cl2)CH2Si(Me2)]2O (6),7u
which crystallizes with two different conformers, in-
tramolecular Sn‚‚‚O distances below the sum of the van

332 Organometallics, Vol. 22, No. 2, 2003
Schulte et al.
is rather small when compared with the corresponding
angles of 144.7(2)-169.3(1)° found in eight-, 10-, and
12-membered metallasiloxanes showing no such in-
tramolecular contacts15a or with the eight-membered
ring 6 (Si-O-Si 144.9(1)°, 145.5(2)°).7u The same angle
might also be indicative for weak or medium ring strain
present in 4. In comparison, the highly strained cyclo-
(Me2SiO)3 and the practically strain-free cyclo-(Me2SiO)4
reveal gas-phase Si-O-Si angles of 131.6(4)° and 144-
(1)°, respectively.15b Similar to compound 6,7u the Si-
(1)-O(1) and Si(2)-O(1) bond distances in compound 4
of 1.646(3) and 1.642(3) Å, respectively, are close to
standard Si-O bond lengths16 and are not affected by
the intramolecular Sn‚‚‚O coordination, a hint at the
ionic character of the latter.
The Sn(2) atom exhibits a distorted tetrahedral con-
figuration (mean angle 109.04°). The intramolecular Sn-
(2)‚‚‚O(1) distance amounts to 3.836(3) Å and exceeds
the sum of the van der Waals radii of oxygen and tin.
The Sn-Cl bond lengths are 2.341(1) Å for Sn(2)-Cl(4)
and 2.355(1) Å for Sn(2)-Cl(3) and are comparable with
Sn-Cl distances reported for diorganotin dichlorides.17
The nonequivalence in the solid state of the two tin
atoms in compound 4 as established by single-crystal
X-ray diffraction analysis is reflected by observation of
two 119Sn CP MAS resonances at δ 98 and 158. Upon
dissolution in CD2Cl2, the nonequivalence is lost on the
119Sn NMR time scale; that is, only a single resonance
is observed at room temperature (δ 120.9) as well as at
-85 °C (δ 118.8). These chemical shifts are slightly low-
frequency shifted with respect to CH2[CH2Sn(Cl2)CH2-
SiMe3]2 (δ 119Sn 132.818) and indicate that the weak
intramolecular Sn‚‚‚O coordination in compound 4
persists in solution.
resonance during the course of the titration indicates
rapid intermolecular exchange of chlorides between 4
and 7.
The negative ion ESMS spectrum of a mixture of 4
and [(Ph3P)2N]+Cl- confirms the results obtained from
119Sn NMR spectroscopy; that is, only the isotopic
cluster patterns shown in Chart 1 were found, with no
indication for the existence of a 1:2 complex [4‚2Cl]2-‚2-
[(Ph3P)2N]+.
The pentachlorodistannate derivative 7 was isolated
as a colorless crystalline solid.
The molecular structure of compound 7 is shown in
Figure 2. Unit cell data, refinement details, and selected
interatomic parameters are listed in Tables 1-3. The
lattice of 7 comprises discrete [cyclo-CH2[CH2Sn(Cl2)CH2-
Si(Me2)]2O‚Cl]- anions and [(Ph3P)2N]+ cations showing
no significant interionic contacts. Both tin atoms in the
anionic part of 7 exhibit a distorted trigonal bipyramidal
14d
geometry (∑ϑeq - ∑ϑax
) 75.5° for Sn(1) and 85.9°
No single crystals suitable for X-ray diffraction analy-
sis could be obtained so far for the 20-membered ring
cyclo-CH 2[CH 2Sn (Cl2)CH 2Si(Me2)OSi(Me2)CH 2Sn -
(Cl2)CH2]2CH2 (5). Its 119Sn CP MAS NMR spectrum
displays two resonances at δ 58 and 119, indicating two
different tin sites with, at least for the former one, a
coordination number higher than four. In CDCl3 solu-
tion, however, the tin atoms are again equivalent on the
119Sn NMR time scale, and a single resonance is
observed at δ 110.2.
Com p lexa tion Beh a vior in Solu tion of cyclo-CH2-
[CH2Sn (Cl2)CH2Si(Me2)]2O (4) towar d Ch lor ide Ion s.
The 119Sn NMR chemical shifts in CDCl3 of 4 to which
various amounts of [(Ph3P)2N]+Cl- had been added (eq
4) indicate quantitative formation of the 1:1 complex
with the chloride ion, [cyclo-CH2[CH2Sn(Cl2)CH2Si-
(Me2)]2O‚Cl]-[(Ph3P)2N]+ (7).
for Sn(2)) with the axial positions being occupied by Cl-
(1), Cl(5) for Sn(1) and Cl(4), Cl(5) for Sn(2). The
remaining chlorine atoms Cl(2) for Sn(1) and Cl(3) for
Sn(2) and the carbon atoms C(1), C(9) for Sn(1) and C(3),
C(4) for Sn(2) define the equatorial planes from which
the Sn(1) and Sn(2) atoms are displaced in direction of
Cl(1) and Cl(4) by 0.162(3) and 0.052(2) Å, respectively.
The bigger distortion from the ideal trigonal bipyrami-
dal configuration for Sn(1) is the result of an additional
intramolecular O(1)‚‚‚Sn(1) contact of 3.428(3) Å being
shorter than the sum of the van der Waals radii13 of
oxygen and tin and making Sn(1) a typical example for
a [5+1] coordination. The Sn-Cl(equatorial) bond lengths
(Sn(1)-Cl(2) 2.362(2), Sn(2)-Cl(3) 2.359(1) Å) are shorter
than the Sn-Cl(axial) ones (Sn(1)-Cl(1) 2.453(2), Sn-
(2)-Cl(4) 2.505(1) Å). The Sn(1)-Cl(5)-Sn(2) bridge is
unsymmetric with Sn(1)-Cl(5) 2.812(1) Å and Sn(2)-
Cl(5) 2.686(1) Å. A similar asymmetry was reported for
the Sn-Cl-Sn bridge in the chloride complex of
1,1,5,5,9,9-hexachloro-1,5,9-tristannacyclododecane.7d The
Si(1)-O(1)-Si(2) bond angle of 150.0(2)° is bigger than
that observed for compound 4 and in line with a longer
intramolecular O(1)‚‚‚Sn(1) distance mentioned above.
Interestingly, even though adduct formation appears
to be almost quantitative, the observation of a single
(15) (a) Beckmann, J .; J urkschat, K. Coord. Chem. Rev. 2001, 215,
267. (b) Oberhammer, H.; Zeil, W.; Fogarasi, G. J . Mol. Struct. 1973,
18, 309.
(16) (a) Barrow, M. J .; Ebsworth, E. A. V.; Harding, M. M. Acta
Crystallogr. Sect. B 1979, 35, 2093. (b) Tomlins, P. E.; Lydon, J . E.;
Akrigg, D.; Sheldrick, B. Acta Crystallogr. Sect. C 1985, 41, 292. (c)
Karle, I. L.; Karle, J . M.; Nielsen, C. J . Acta Crystallogr. Sect. C 1986,
42, 64.
(17) Kolb, U.; Dra¨ger, M.; J ousseaume, B. Organometallics 1991,
10, 2737.
(18) Dakternieks, D.; J urkschat, K.; Schollmeyer, D.; Wu, H. Or-
ganometallics 1994, 13, 4121.
In CDCl3 solution of 7, both tin atoms are pentaco-
ordinated as evidenced by (i) the 119Sn NMR chemical
shift of δ -55.7 ppm being low-frequency shifted with
respect to tetracoordinated compound 4 (δ 117.8) and
(ii) the observation of increased 1J (117/119Sn-13C) and
2J (117/119Sn-1H) couplings of 407/426, 125/130 Hz for

Tin- and Silicon-Containing Rings
Organometallics, Vol. 22, No. 2, 2003 333
Sch em e 2
F igu r e 2. General view (SHELXTL) of the anion in 7
showing 30% probability displacement ellipsoids and the
atom-numbering scheme. The cation (Ph3P)2N+ is omitted
for clarity.
SiCH2Sn and 635/669, 77/81 Hz for CH2CH2Sn, respec-
tively, in comparison with the corresponding couplings
measured for compound 4 (261/273, 101/106 Hz for
SiCH2Sn; 482/504, 67 Hz for CH2CH2Sn). At room
temperature, the chloride bridge in 7 is symmetric on
1
manner.19a Elemental analysis as well as H, 13C, 29Si,
and 119Sn NMR spectroscopy (see Experimental Section)
confirmed the purity of the polymer 8. However, obtain-
ing information on the molecular weight distribution
using MALDI-MS and gel-permeation chromatography
failed. The negative ion ESMS spectrum (see Supporting
Information) of a solution of compound 8 in acetonitrile
showed a large number of overlapping cluster patterns
between m/z ) 1000 and 2500, corresponding to nega-
tive charge uptakes of 0.6 to 0.25 per monomeric unit.
No molecular weight distribution could be estimated
from this spectrum.
1
the H, 13C, 29Si, and 119Sn NMR time scales; that is,
the methyl groups and methylene groups as well as the
silicon and tin atoms are equivalent. The equivalence
1
of the methyl groups in the H and 13C NMR spectra
indicates the chloride complex 7 to be kinetically labile.
The 20-membered ring 5 was insufficiently soluble in
CDCl3 to allow a similar 119Sn NMR investigation.
Con clu sion . Diorganohydridosilylmethyl- as well as
diorganoisopropoxysilyl-functionalized spacer-bridged
ditin compounds of the general type Me2(R)SiCH2(Ph2)-
Sn(CH2)nSn(Ph2)CH2Si(R)Me2 (R ) H, i-PrO; n ) 1, 3)
are easily accessible synthons for the convenient one-
pot synthesis of both silicon- and tin-containing rings
cyclo-(CH2)n[Sn(Cl2)CH2Si(Me2)]2O (n ) 1, 3). Appar-
ently, the ability to undergo acid-catalyzed ring-opening
polymerization is higher for n ) 3 than for n ) 1. The
reason for this is not quite clear but might be related
to the greater intramolecular Sn‚‚‚O distance (weaker
bond) in the 10-membered ring 4, facilitating protona-
tion of the oxygen atom in the latter. Along the polym-
erization pathways, oligomers such as the 20-membered
ring cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)OSi(Me2)CH2Sn-
(Cl2)CH2]2CH2 appear as intermediates and can be
isolated.
The complexation behavior in solution of cyclo-
CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) toward fluoride ions
has also been studied, but none of the compounds
identified by NMR spectroscopy were isolated (see
Supporting Information).
Rin g-Op en in g P olym er iza tion of cyclo-CH2[CH2-
Sn (Cl2)CH2Si(Me2)]2O (4) a n d of cyclo-CH2[CH2Sn -
(Cl2)CH2Si(Me2)OSi(Me2)CH2Sn (Cl2)CH2]2CH2 (5).
No oligo- or polymerization was observed after three
weeks at room temperature of the 10-membered ring 4
which had been dissolved in toluene. However, upon
standing for several days in CH2Cl2 solution at ambient
temperature and as monitored by 29Si NMR spectros-
copy, the 10-membered ring 4 is converted almost
quantitatively into the 20-membered ring 5, the latter
being poorly soluble in this solvent, and precipitates
analytically pure from the solution. In the more polar
solvent acetone, the 20-membered ring 5 is more soluble,
and a solution of compound 4 in this solvent is converted
into a mixture of higher oligomers after several hours
already. By heating at reflux and addition of catalytic
amounts of p-toluenesulfonic acid, solutions of both the
10- and 20-membered rings 4 and 5, respectively, are
quantitatively converted into solutions of the polymer
poly-[Si(Me2)CH2Sn(Cl2)(CH2)3Sn(Cl2)CH2Si(Me2)O] (8)
(Scheme 2).
Exp er im en ta l Section
Gen er a l Meth od s. All reactions were carried out under an
atmosphere of dry argon. The solvents were purified by
distillation from appropriate drying agents under argon.
Mercuric chloride and bis(triphenylphosphoranylidene)am-
monium chloride were commercial products. Bis(diphenyl-
fluorostannyl)methane,7p bis(diphenylfluorostannyl)propane,10
(chloromethyl)dimethylsilane,13 and (chloromethyl)dimeth-
ylisopropoxysilane19b were synthesized according to litera-
ture methods. The density of the crystals was measured using
Compound 8 is a waxlike solid, which melts in the
range 93-105 °C. It is soluble in CH2Cl2, CHCl3, thf,
acetone and acetonitrile but almost insoluble in n-
hexane. The polymerization of the six-membered ring
cyclo-Cl2Sn[CH2Si(Me2)]2O was achieved in a similar
(19) (a) Mironov, V. F.; Shiryaev, V. I.; Stepina, EÄ . M.; Makhalkina,
L. V.; Lapina, A. I.; Bochkarev, V. N.; Nechaeva, A. I. J . Gen. Chem.
USSR 1976, 46, 1039. (b) Andrianov, K. A.; Golubenko, A. J . Gen.
Chem. USSR 1975, 45, 2614.

334 Organometallics, Vol. 22, No. 2, 2003
Schulte et al.
a Micromeritics Accu Pyc 1330. Elemental analyses were
performed on a LECO-CHNS-932 analyzer. Molecular weights
were measured osmometrically using a Knauer osmometer.
NMR Sp ectr oscop y. NMR spectra in solution were re-
corded on Bruker DRX400 and Bruker DPX 300 FT NMR
spectrometers with broadband decoupling of 13C at 100.63
MHz, 19F at 282.41 MHz, 29Si at 79.49 MHz, 31P at 161.98 MHz,
and 119Sn at 149.21 MHz using an internal deuterium lock.
1H, 13C, 19F, 29Si, 31P, and 119Sn NMR chemical shifts δ are
given in ppm and referenced to external Me4Si (1H,13C, 29Si),
CFCl3 (19F), 85% aqueous H3PO4 (31P), and Me4Sn (119Sn),
respectively. Temperatures were maintained using a Bruker
control system. The NMR spectra were recorded at room
temperature if not otherwise stated. The complexes for NMR
investigations were generally prepared in situ, and the con-
centration of the compounds 4 and 5 was about 0.1 M. 119Sn-
{1H} MAS NMR spectra were recorded on a Bruker MSL 400
spectrometer using cross polarization and high-power proton
decoupling (contact time 3.5 ms, MAS speeds 4500, 6000, 8000
Hz). Tetracyclohexyltin was used as a second reference (δ
-97.35 ppm against SnMe4).
Cr ysta llogr a p h y. Crystals of cyclo-CH2[CH2Sn(Cl2)CH2Si-
(Me2)]2O (4) and [cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O‚Cl]--
[(Ph3P)2N]+ (7) were grown from hexane and CH2Cl2/hexane
solutions, respectively, by slow evaporation of the solvents.
Intensity data for the colorless crystals were collected on a
Nonius KappaCCD diffractometer with graphite-monochro-
mated Mo KR radiation. The data collection covered almost
the whole sphere of reciprocal space with 360 frames via
ω-rotation (∆∆/ω ) 1°) at two times 10 s for 4 and two times
5 s for 7 per frame. The crystal-to-detector distance was 2.7
cm (4) and 2.8 cm (7) with a detector-θ-offset of 5°. Crystal
decay was monitored by repeating the initial frames at the
end of data collection. Analyzing the duplicate reflections there
was no indication for any decay. The structures were solved
by direct methods using SHELXS9720 and successive difference
Fourier syntheses. Refinement involved applying full-matrix
least-squares methods using SHELXL97.21
The H atoms were placed in geometrically calculated
positions using a riding model and refined with a common
isotropic temperature factor for different C-H types (C-Hprim.
0.96 Å, C-Hsec. 0.97 Å, Uiso 0.104(4) Å2 (4), 0.112(4) Å2 (7),
Caryl-H 0.93 Å (7), Uiso 0.083(4) Å2 (7)).
Atomic scattering factors for neutral atoms and real and
imaginary dispersion terms were taken from the literature.22
The figures were created by SHELXTL.23 Crystallographic
data are given in Table 1, selected bond distances (Å) in Table
2, and bond angles (deg) in Table 3.
Electr osp r a y Ma ss Sp ectr om etr y. Electrospray mass
spectra were obtained with a Platform II single quadrupole
mass spectrometer (Micromass, Altrincham, UK) using an
acetonitrile mobile phase. Approximately 1 mg of each com-
pound was placed in 1 mL of acetonitrile and sonicated for 10
min. The solutions were injected directly into the spectrometer
via a Rheodyne injector equipped with a 100 µL loop. A
Harvard 22 syringe pump delivered the solutions to the
vaporization nozzle of the electrospray ion source at a flow rate
of 20 µL min-1. Nitrogen was used as both a drying gas and
for nebulization with flow rates of approximately 200 and 15
mL min-1, respectively. Pressure in the mass analyzer region
was usually about 3 × 10-5 mbar. Typically 10 signal-averaged
spectra were collected.
g, 18.0 mmol) in thf (60 mL) was added dropwise at 0 °C a
0.545 M solution of Me2(H)SiCH2MgCl (66.0 mL, 36.0 mmol)
in thf that was prepared from Me2(H)SiCH2Cl (4.87 g, 45.0
mmol) and magnesium turnings (1.46 g, 60.0 mmol). The
reaction mixture was stirred at room temperature for 16 h
before removing the solvent in vacuo. Hexane (100 mL) was
added to the residue, and after stirring thoroughly the mixture
was filtered, the procedure being repeated two times. The
solvent was removed in vacuo to give 12.95 g (17.6 mmol, 98%)
of CH2[CH2Sn(Ph2)CH2Si(H)Me2]2 (1) as a colorless oil. 1H
NMR (C6D6): δ 0.14 (d, 12H, 1J (13C-1H) ) 120 Hz, 2J (29Si-
3
1
1H) ) 6 Hz, J (1H-1H) ) 4 Hz, CH3), 0.21 (d, 4H, J (13C-1H)
2
3
) 120 Hz, J (29Si-1H) ) 7 Hz, J (1H-1H) ) 4 Hz, SiCH2Sn),
1.51 (t, 4H, 1J (13C-1H) ) 112 Hz, 2J (117/119Sn-1H) ) 52 Hz,
3J (1H-1H) ) 8 Hz, CH2CH2Sn), 2.17 (quint, 2H, 1J (13C-1H) )
117 Hz, J (117/119Sn-1H) ) 65/68 Hz, J (1H-1H) ) 8 Hz, CH2-
3
3
CH2Sn), 4.48 (m, 2H, J (29Si-1H) ) 183 Hz, J (1H-1H) 4 Hz,
SiH), 7.30 (m, 12H, Hm/Hp), 7.61 (dd, 8H, 3J (117/119Sn-1H) )
46 Hz, 3J (1H-1H) ) 8 Hz, 4J (1H-1H) ) 2 Hz, Ho). 13C{1H} NMR
(C6D6): δ -8.49 (s, 1J (117/119Sn-13C) ) 231/243 Hz, 1J (29Si-
13C) ) 48 Hz, CH2Si), -0.94 (s, 1J (29Si-13C) ) 51 Hz,
3J (117/119Sn-13C) ) 17 Hz, CH3), 17.03 (s, 1J (117/119Sn-13C) )
353/370 Hz, 3J (117/119Sn-13C) ) 65 Hz, CH2CH2Sn), 24.74 (s,
2J (117/119Sn-13C) ) 21 Hz, CH2CH2Sn), 128.65 (s, 3J (117/119Sn-
13C) ) 46 Hz, Cm), 128.86 (s, 4J (117/119Sn-13C) ) 10 Hz, Cp),
137.00 (s, 2J (117/119Sn-13C) ) 35 Hz, Co), 140.52 (s, 1J (117/119Sn-
13C) ) 442/462 Hz, Ci). 29Si{1H} NMR (C6D6): δ -13.1 (s,
1
3
1J (13CH3-29Si) ) 51 Hz, J (13CH2-29Si) ) 49 Hz, J (117/119Sn-
1
2
29Si) ) 26 Hz). 119Sn{1H} NMR (C6D6): δ -64.0 (s, 1J (13Ci-
119Sn) ) 462 Hz, J (CH213CH2-119Sn) ) 370 Hz, J (Si13CH2-
1
1
119Sn) ) 244 Hz, J (13Co-119Sn) ) 36 Hz, J (29Si-119Sn) ) 26
Hz, 3J (13Cm-119Sn) ) 47 Hz). Anal. Calcd for C33H44Si2Sn2
(734.30): C, 54.0; H, 6.0. Found: C, 54.1; H, 6.2.
2
2
Syn th esis of Bis{[(d im eth ylsilyl)m eth yl]d ip h en ylsta n -
n yl}m eth a n e, CH2[Sn (P h 2)CH2Si(H)Me2]2 (2). To a suspen-
sion of bis(diphenylfluorostannyl)methane (10.00 g, 16.7 mmol)
in thf (70 mL) was added dropwise at 0 °C a 0.493 M solution
of Me2(H)SiCH2MgCl (70.0 mL, 33.5 mmol) in thf that was
prepared from Me2(H)SiCH2Cl (3.80 g, 35.0 mmol) and mag-
nesium turnings (1.22 g, 50.0 mmol). The reaction mixture was
stirred at room temperature for 15 h before removing the
solvent in vacuo. Hexane (100 mL) was added to the residue,
and after stirring thoroughly the mixture was filtered, the
procedure being repeated two times. The solvent was removed
in vacuo to give 11.34 g (16.1 mmol, 96%) of CH2[Sn(Ph2)CH2-
1
Si(H)Me2]2 (2) as a colorless oil. H NMR (CDCl3): δ 0.00 (d,
1
2
3
12H, J (13C-1H) ) 121 Hz, J (29Si-1H) ) 7 Hz, J (1H-1H) )
4 Hz, CH3), 0.08 (d, 4H, 1J (13C-1H) ) 119 Hz, 2J (117/119Sn-
1H) ) 71/75 Hz, 3J (1H-1H) ) 4 Hz, SiCH2Sn), 0.72 (s, 2H,
1J (13C-1H) ) 126 Hz, 2J (117/119Sn-1H) ) 59/62 Hz, SnCH2Sn),
4.11 (m, 2H, J (29Si-1H) ) 182 Hz, J (1H-1H) ) 4 Hz, SiH),
1
3
7.31 (m, 12H, Hm/Hp), 7.43 (m, 8H, J (117/119Sn-1H) ) 47 Hz,
3
Ho). 13C{1H} NMR (CDCl3): δ -14.73 (s, 1J (117/119Sn-13C) )
269/281 Hz, SnCH2Sn), -7.02 (s, J (117/119Sn-13C) ) 253/264
1
Hz, J (29Si-13C) ) 47 Hz, SiCH2Sn), -1.20 (s, J (29Si-13C) )
50 Hz, 3J (117/119Sn-13C) ) 19 Hz, CH3), 128.17 (s, 3J (117/119Sn-
13C) ) 49 Hz, Cm), 128.53 (s, 4J (117/119Sn-13C) ) 11 Hz, Cp),
136.48 (s, 2J (117/119Sn-13C) ) 38 Hz, Co), 140.94 (s, 1J (117/119Sn-
13C) ) 465/487 Hz, 3J (117/119Sn-13C) ) 11 Hz, Ci). 29Si{1H} NMR
(CDCl3): δ -13.8 (s, 1J (13CH3/13CH2-29Si) ) 49 Hz, 2J (117/119Sn-
1
1
29Si) ) 26 Hz). 119Sn{1H} NMR (CDCl3): δ -37.6 (s, 1J (13Ci-Ph
-
119Sn) ) 492 Hz, 1J (Sn13CH2-119Sn) ) 280 Hz, 1J (Si13CH2-
119Sn) ) 262 Hz, 2J (117Sn-119Sn) ) 243 Hz, 2J (29Si-119Sn) )
25 Hz). Anal. Calcd for C31H40Sn2Si2 (706.25): C, 52.7; H, 5.7.
Found: C, 52.7; H, 5.8.
Syn th esis of 1,3-Bis{[(d im eth ylsilyl)m eth yl]d ip h en yl-
sta n n yl}p r op a n e, CH2[CH2Sn (P h 2)CH2Si(H)Me2]2 (1). To
a suspension of 1,3-bis(diphenylfluorostannyl)propane (11.26
Syn t h esis of 1,1,5,5-Tet r a ch lor o-7,7,9,9-t et r a m et h -
yl-7,9-d isila -1,5-d ist a n n a -8-oxa cyclod eca n e, cyclo-CH 2-
[CH2Sn (Cl2)CH2Si(Me2)]2O (4), a n d 1,1,5,5,11,11,15,15-
Oct a ch lor o-7,7,9,9,17,17,19,19-oct a m e t h yl-8,18-d ioxa -
7,9,17,19-tetr a sila -1,5,11,15-tetr a sta n n a cycloeicosa n e, cy-
cl o-C H 2[C H 2S n (C l2)C H 2S i(Me 2)O S i(Me 2)C H 2S n (C l2)-
(20) Sheldrick, G. M. Acta Crystallogr., Sect. A 1990, 467.
(21) Sheldrick, G. M. SHELXL97; University of Go¨ttingen, 1997.
(22) International Tables for Crystallography; Kluwer Academic
Publishers: Dordrecht, 1992; Vol. C.
(23) Sheldrick, G. M. SHELXTL, release 5.1; Siemens Analytical
X-ray Instruments Inc.: Madison, WI, 1997.

Tin- and Silicon-Containing Rings
Organometallics, Vol. 22, No. 2, 2003 335
CH2]2CH2 (5). Meth od A. To a solution of 1,3-bis{[(dimethyl-
silyl)methyl]diphenylstannyl}propane (1) (5.00 g, 6.81 mmol)
in acetone (40 mL) at 0 °C was added dropwise a solution of
HgCl2 (7.39 g, 27.2 mmol) in acetone (40 mL). The resulting
suspension was stirred overnight at room temperature before
removing the PhHgCl by filtration. After removing the solvent
in vacuo the residue was suspended in 30 mL of CH2Cl2 and
the suspension was filtered. The filtrate was allowed to stand
overnight at 5 °C, giving 0.54 g (0.46 mmol, 14%) of cyclo-
CH2[CH2Sn(Cl2)CH2Si(Me2)OSi(Me2)CH2Sn(Cl2)CH2]2CH2 (5)
as a colorless solid, mp 181-184 °C. After filtration from
compound 5 the solvent was removed in vacuo and the residue
was suspended in 50 mL of hot hexane. The suspension was
filtered, the filtrate collected, and the procedure repeated with
another 50 mL of hot hexane. The combined filtrates were
allowed to stand overnight at 5 °C, giving 0.59 g (1.01 mmol,
15%) of cyclo-CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) as a colorless
crystalline solid, mp 96-98 °C. The filtrate was dissolved in
10 mL of CH2Cl2 and another 0.77 g (1.13 mmol, 17%) of cyclo-
CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) isolated by size exclusion
chromatography (100 g Sephadex LH20, CH2Cl2).
(t, 4H, 1J (13C-1H) ) 135 Hz, 2J (117/119Sn-1H) ) 54 Hz, 3J (1H-
1H) ) 8 Hz, CH2CH2Sn), 2.08 (m, 2H, 3J (1H-1H) ) 8 Hz, CH2-
1
3
CH2Sn), 4.03 (sept, 2H, J (13C-1H) ) 129 Hz, J (1H-1H) ) 6
3
Hz, CH(CH3)2), 7.40 (m, 12H, Hm,p), 7.57 (m, 8H, J (117/119Sn-
1H) ) 45 Hz, Ho). 13C{1H} NMR (CDCl3): δ -4.84 (s,
1
1J (117/119Sn-13C) ) 227/239 Hz, J (29Si-13C) ) 58 Hz, SiCH2-
1
3
Sn), 1.18 (s, J (29Si-13C) ) 58 Hz, J (117/119Sn-13C) ) 10 Hz,
SiCH3), 17.26 (s, J (117/119Sn-13C) ) 360/375 Hz, J (117/119Sn-
1
3
13C) ) 68 Hz, CH2CH2Sn), 24.32 (s, J (117/119Sn-13C) ) 20 Hz,
2
CH2CH2Sn), 25.77 (s, J (29Si-13C) ) 21 Hz, CH(CH3)2), 64.66
3
(s, OCH), 128.05 (s, J (117/119Sn-13C) ) 46 Hz, Cm), 128.28 (s,
3
4J (117/119Sn-13C) ) 10 Hz, Cp), 136.67 (s, 2J (117/119Sn-13C) )
36 Hz, Co), 140.77 (s, J (117/119Sn-13C) ) 439/458 Hz, Ci). 29Si-
1
{1H} NMR (CDCl3): δ 14.9 (s, J (13CH2/13CH3-29Si) ) 58 Hz,
1
2J (117/119Sn-29Si) ) 19 Hz). 119Sn{1H} NMR (CDCl3): δ -65.4
(s, 1J (13Ci-119Sn) ) 459 Hz, 1J (CH213CH2-119Sn) ) 376 Hz,
1J (Si13CH2-119Sn) ) 239 Hz, 3J (13Cm-119Sn) ) 47 Hz, 4J (117Sn-
119Sn) ) 71 Hz).
A solution of HgCl2 (9.54 g, 35.1 mmol) in acetone (60 mL)
was added dropwise at 0 °C over a period of 1 h to a solution
of 1,3-bis{[(dimethylisopropoxysilyl)methyl]diphenylstannyl}-
propane (3) (7.47 g, 8.78 mmol) in acetone (60 mL). The
reaction mixture was stirred for 14 h at room temperature
before removing the PhHgCl by filtration. The solvent was
removed in vacuo and the residue extracted two times with
100 mL of hot n-hexane. The combined extracts were kept
overnight at -25 °C, giving a precipitate. The latter was
filtered and dried to give 2.10 g (3.61 mmol, 41%) of cyclo-
CH2[CH2Sn(Cl2)CH2Si(Me2)]2O (4) as a colorless crystalline
solid.
Sp ectr oscop ic Da ta for 4. 1H NMR (CDCl3): δ 0.31 (s,
1
2
12H, J (13C-1H) ) 119 Hz, J (29Si-1H) ) 7 Hz, CH3), 1.06 (s,
4H, 1J (13C-1H) ) 125 Hz, 2J (117/119Sn-1H) ) 101/106 Hz,
2J (29Si-1H) ) 6 Hz, SiCH2Sn), 1.97 (t, 4H, J (13C-1H) ) 134
1
Hz, J (117/119Sn-1H) ) 67 Hz, J (1H-1H) ) 7 Hz, CH2CH2Sn),
2
3
2.49 (quint, 2H, J (13C-1H) ) 133 Hz, J (117/119Sn-1H) ) 160/
168 Hz, 3J (1H-1H) ) 7 Hz, CH2CH2Sn). 13C{1H} NMR
(CDCl3): δ 2.98 (s, 1J (29Si-13C) ) 60 Hz, 3J (117/119Sn-13C) )
26 Hz, CH3), 14.62 (s, 1J (117/119Sn-13C) ) 261/273 Hz, 1J (29Si-
13C) ) 54 Hz, SiCH2Sn), 20.51 (s, 2J (117/119Sn-13C) ) 29 Hz,
CH2CH2Sn),31.14 (s, 1J (117/119Sn-13C))482/504 Hz, 3J (117/119Sn-
13C) ) 53 Hz, CH2CH2Sn). 29Si{1H} NMR (CDCl3): δ 12.2 (s,
1
3
Syn th esis of 1,1,3,3-Tetr a ch lor o-5,5,7,7-tetr a m eth yl-
1,7-d ista n n a -3,5-d isila -4-oxa cycloocta n e, cyclo-CH2[Sn -
(Cl2)CH2Si(Me2)]2O (6). To a solution of bis{[(dimethylsilyl)-
methyl]diphenylstannyl}methane (2) (11.00 g, 15.6 mmol) in
acetone (80 mL) at 0 °C was added dropwise a solution of HgCl2
(16.92 g, 62.3 mmol) in acetone (80 mL). The resulting
suspension was stirred at room temperature for 14 h before
removing the PhHgCl by filtration. After removing the solvent
in vacuo the residue was suspended in 100 mL of hot hexane.
The suspension was filtered, the filtrate collected, and the
procedure repeated with another 100 mL of hot hexane. The
combined filtrates were allowed to stand overnight at 5 °C,
giving 2.93 g (5.30 mmol, 34%) of cyclo-O[Si(Me2)CH2Sn(Cl2)]2-
CH2 (6) as a colorless crystalline solid, mp 107-109 °C. 1H
1J (13CH2-29Si) ) 55 Hz, J (13CH3-29Si) ) 60 Hz, J (117/119Sn-
1
2
29Si))36 Hz). 119Sn{1H}NMR (CDCl3): δ117.8 (s, 1J (CH213CH2-
119Sn) ) 499 Hz, J (Si13CH2-119Sn) ) 278 Hz). 119Sn{1H} CP-
1
MAS NMR: δ 98, 158. Anal. Calcd for C9H22Cl4OSi2Sn2
(581.68): C, 18.6; H, 3.8; Cl, 24.4. Found: C, 18.9; H, 3.9; Cl,
24.0. Mol wt: (VPO, C6H6): 673 (calcd 582).
1
Sp ectr oscop ic Da ta for 5. H NMR (acetone-d6): δ 0.31
1
2
(s, 24H, J (13C-1H) ) 119 Hz, J (29Si-1H) ) 7 Hz, CH3), 1.15
(s, 8H, 1J (13C-1H) ) 124 Hz, 2J (117/119Sn-1H) ) 100/104 Hz,
2J (29Si-1H) ) 6 Hz, SiCH2Sn), 2.03 (t, 8H, J (13C-1H) ) 137
1
Hz, J (117/119Sn-1H) ) 67 Hz, J (1H-1H) ) 8 Hz, CH2CH2Sn),
2.35 (quint, 4H, 3J (117/119Sn-1H) ) 90/95 Hz, 3J (1H-1H) ) 8
Hz, CH2CH2Sn). 13C{1H} NMR (acetone-d6): δ 3.27 (s, 1J (29Si-
13C) ) 60 Hz, 3J (117/119Sn-13C) ) 20 Hz, CH3), 16.71 (s,
2
3
1
2
NMR (CDCl3): δ 0.31 (s, 12H, J (13C-1H) ) 120 Hz, J (29Si-
1H) ) 7 Hz, CH3), 1.21 (s, 4H, 1J (13C-1H) ) 127 Hz, 2J (117/119Sn-
1H) ) 115/121 Hz, SiCH2Sn), 1.70 (s, 2H, 1J (13C-1H) ) 137
Hz, 2J (117/119Sn-1H) ) 76/80 Hz, SnCH2Sn). 13C{1H} NMR
(CDCl3): δ 2.67 (s, 1J (29Si-13C) ) 61 Hz, 3J (117/119Sn-13C) )
22 Hz, CH3), 13.89 (s, 1J (117/119Sn-13C) ) 335/351 Hz, 1J (29Si-
1J (117/119Sn-13C) ) 343/360 Hz, J (29Si-13C) ) 55 Hz, SiCH2-
1
Sn), 22.01 (s, J (117/119Sn-13C) ) 35 Hz, CH2CH2Sn), 33.36 (s,
2
1J (117/119Sn-13C) ) 527/551 Hz, 3J (117/119Sn-13C) ) 120/125 Hz,
CH2CH2Sn). 29Si{1H} NMR (acetone-d6): δ 9.4 (s, 1J (13CH2-
1
13C) ) 55 Hz, SiCH2Sn), 16.91 (s, J (117/119Sn-13C) ) 370/387
1
2
29Si) ) 56 Hz, J (13CH3-29Si) ) 60 Hz, J (117/119Sn-29Si) ) 32
Hz). 119Sn{1H} NMR (acetone-d6): δ 43.9 (s, 4J (119Sn-117Sn)
) 328 Hz). 119Sn{1H} CP-MAS NMR: δ 58, 119. Anal. Calcd
for C18H44Cl8O2Si4Sn4 (1163.35): C, 18.6; H, 3.8. Found: C,
18.7; H, 3.9. Mol wt: (VPO, acetone): 1205 (calcd 1163).
Meth od B (for the synthesis of 4). To a suspension of 1,3-
bis(diphenylfluorostannyl)propane (8.83 g, 14.1 mmol) in thf
(50 mL) was added dropwise at 0 °C a solution of Me2(i-
PrO)SiCH2MgCl (28.2 mmol) in thf (70 mL), which had been
prepared from (chloromethyl)dimethylisopropoxysilane and
magnesium turnings. The reaction mixture was stirred at room
temperature for 15 h before removing the solvent in vacuo.
Hexane (100 mL) was added to the residue, and after stirring
thoroughly the mixture was filtered, the procedure being
repeated two times. The solvent was removed in vacuo to give
11.48 g (13.5 mmol, 96%) of CH2[CH2Sn(Ph2)CH2Si(i-PrO)Me2]2
Hz, SnCH2Sn). 29Si{1H} NMR (CDCl3): δ 14.2 (s, 2J (117/119Sn-
29Si) ) 56/59 Hz). 119Sn{1H} NMR (CDCl3): δ 109.0 (s,
2J (117Sn-119Sn) ) 419 Hz). 119Sn{1H} CP-MAS NMR: δ 87,
114. Anal. Calcd for C7H18Cl4OSn2Si2 (553.62): C, 15.2; H, 3.3.
Found: C, 15.2; H, 3.3. Mass spectrum: m/e (%) 59 (11.83,
[CH3SiO]+), 117 (11.59, [C3H9Si2O]+), 131 (52.65, [C4H11OSi2]+),
539 (100.00, [M - CH3]+, 35Cl337Cl118Sn120Sn). Mol wt: (VPO,
CH2Cl2) 547 (calcd 554).
Syn t h esis of Bis(t r ip h en ylp h osp h or a n ylid en e)a m -
monium-1,1,5,5-tetrachloro-7,7,9,9-tetramethyl-7,9-disila-1,5-
d ista n n a -8-oxa cyclod eca n e ch lor id e, [cyclo-CH2[CH2Sn -
(Cl2)CH2Si(Me2)]2O‚Cl]-[(P h 3P )2N]+ (7). To a solution of
1,1,5,5-tetrachloro-7,7,9,9-tetramethyl-7,9-disila-1,5-distanna-
8-oxacyclodecane (4) (200 mg, 0.34 mmol) in CH2Cl2 (10 mL)
was added bis(triphenylphosphoranylidene)ammonium chlo-
ride (197 mg, 0.34 mmol). The mixture was stirred at room
temperature for 10 min and the solvent removed in vacuo to
give 397 mg (0.34 mmol, 100%) of [cyclo-CH2[CH2Sn(Cl2)CH2-
Si(Me2)]2O‚Cl]-[(Ph3P)2N]+ (7) as a colorless crystalline solid,
mp 176-178 °C. 1H NMR (CDCl3): δ 0.24 (s, 12H, 1J (13C-1H)
1
(3) as a colorless oil of sufficient purity. H NMR (CDCl3): δ
0.12 (s, 12H, 1J (13C-1H) ) 120 Hz, SiCH3), 0.36 (s, 4H, 1J (13C-
1H) ) 118 Hz, 2J (117/119Sn-1H) ) 73 Hz, SiCH2Sn), 1.17 (d,
12H, 1J (13C-1H) ) 127 Hz, 3J (1H-1H) ) 6 Hz, CH(CH3)2), 1.53

336 Organometallics, Vol. 22, No. 2, 2003
Schulte et al.
2
1
1
2
) 118 Hz, J (29Si-1H) ) 7 Hz, CH3), 1.19 (s, 4H, J (13C-1H)
SiCH2Sn), 1.89 (t, 4H, J (13C-1H) ) 150 Hz, J (117/119Sn-1H)
2
2
3
) 128 Hz, J (117/119Sn-1H) ) 125/130 Hz, J (29Si-1H) ) 6 Hz,
) 50/53 Hz, J (1H-1H) ) 8 Hz, CH2CH2Sn), 2.31 (quint, 2H,
SiCH2Sn), 2.01 (t, 4H, J (13C-1H) ) 120 Hz, J (117/119Sn-1H)
3J (117/119Sn-1H) ) 88/92 Hz, J (1H-1H) ) 8 Hz, CH2CH2Sn).
1
2
3
) 77/81 Hz, J (1H-1H) ) 6 Hz, CH2CH2Sn), 2.49 (quint, 2H,
13C{1H} NMR (acetone-d6): δ 3.27 (s, 1J (29Si-13C) ) 61 Hz,
3J (117/119Sn-13C) ) 15 Hz, CH3), 16.63 (s, 1J (117/119Sn-13C) )
346/362 Hz, 1J (29Si-13C) ) 54 Hz, SiCH2Sn), 21.87 (s,
3
1J (13C-1H) ) 130 Hz, J (117/119Sn-1H) ) 200/209 Hz, J (1H-
1H) ) 6 Hz, CH2CH2Sn), 7.40-7.67 (m, 30H, PhP). 13C{1H}
NMR (CDCl3): δ 3.26 (s, 1J (29Si-13C) ) 61 Hz, 3J (117/119Sn-
3
3
2J (117/119Sn-13C) ) 38 Hz, CH2CH2Sn), 32.96 (s, J (117/119Sn-
1
13C) ) 35 Hz, CH3), 20.84 (s, J (117/119Sn-13C) ) 38 Hz, CH2-
13C) ) 530/555 Hz, 3J (117/119Sn-13C) ) 124/129 Hz, CH2CH2-
Sn). 29Si{1H} NMR (acetone-d6): δ 7.7 (s, 1J (13CH2-29Si) ) 54
Hz, 1J (13CH3-29Si) ) 61 Hz, 2J (117/119Sn-29Si) ) 20 Hz). 119Sn-
2
CH2Sn), 23.77 (s, J (117/119Sn-13C) ) 407/426 Hz, J (29Si-13C)
1
1
) 59 Hz, SiCH2Sn), 38.12 (s, J (117/119Sn-13C) ) 635/669 Hz,
1
3J (117/119Sn-13C) ) 39 Hz, CH2CH2Sn), 126.78-133.82 (4
signals with 31P-couplings, PhP). 29Si{1H} NMR (CDCl3): δ 9.2
(s, 1J (13CH2-29Si) ) 65 Hz, 1J (13CH3-29Si) ) 60 Hz, 2J (117/119Sn-
{1H} NMR (acetone-d6): δ 42.1 (s, J (119Sn-117Sn) ) 346 Hz).
4
Anal. Calcd for 1/n(C9H22Cl4OSi2Sn2)n‚1/n(581.68)n: C, 18.6;
H, 3.8. Found: C, 18.9; H, 3.8.
29Si) ) 44 Hz). 31P{1H} NMR (CDCl3): δ 21.8 (s, J (13Ci-31P)
1
) 108 Hz). 119Sn{1H} NMR (CDCl3): δ -55.7 (s, 1J (CH213CH2-
Ack n ow led gm en t. We are grateful to the Deutsche
Forschungsgemeinschaft, the Fonds der Chemischen
Industrie, and the Australian Research Council for
financial support. A.D. thanks the Freundesgesellschaft
der Universita¨t Dortmund for supporting a three month
stay at Dortmund University.
119Sn) ) 671 Hz, J (Si13CH2-119Sn) ) 425 Hz, J (29Si-119Sn)
) 43 Hz). Anal. Calcd for C45H52Cl5NOP2Si2Sn2 (1155.72): C,
46.8; H, 4.5; N, 1.2; Cl, 15.3. Found: C, 47.2; H, 4.7; N, 1.2;
Cl, 14.9.
1
2
Syn t h esis of p oly-[Si(Me2)CH 2Sn (Cl2)(CH 2)3Sn (Cl2)-
CH2Si(Me2)O] (8). A solution of 1,1,5,5,11,11,15,15-octachloro-
7,7,9,9,17,17,19,19-octamethyl-8,18-dioxa-7,9,17,19-tetrasila-
1,5,11,15-tetrastannacycloeicosane (5) (0.15 g, 0.13 mmol) and
a trace amount of para-toluenesulfonic acid in 5 mL of acetone
was heated to reflux for 2 days. The solvent was removed in
vacuo, giving 0.15 g (100%) of poly-[OSi(Me2)CH2Sn(Cl2)(CH2)3-
Sn(Cl2)CH2Si(Me2)] (8) as a colorless waxy solid, mp 93-105°C.
Su p p or tin g In for m a tion Ava ila ble: Tables of all coor-
dinates, anisotropic displacement parameters, and geometric
data for compounds 4 and 7. The discussion of the complex-
ation behavior of compound 4 toward fluoride ions and the
ESMS spectrum of compound 8. This material is available free
of charge via the Internet at http://pubs.acs.org.
1H NMR (CDCl3): δ 0.29 (s, 12H, J (13C-1H) ) 119 Hz, CH3),
1
1.01 (s, 4H, 1J (13C-1H) ) 118 Hz, 2J (117/119Sn-1H) ) 88/92 Hz,
OM020740B