Organotin compounds bearing mesogenic sidechains: Synthesis, X-ray structures and polymerisation chemistry

Article abstract of DOI:10.1016/j.jorganchem.2003.08.003

Organotin compounds R₃Sn(CH₂)_n+2OC ₆H₄C₆H₄Y (R₃=Ph ₃, Ph₂Bu; Y=H, CN; n =1-3) and RX₂Sn (CH₂)_n+2OC₆H₄C₆ H₄Y (R=Ph, Bu; Y=H, CN; X=Br, I; n=1-3) have been synthesised and characterised by ¹H-, ¹³C-, ¹¹⁹ Sn-NMR and M?ssbauer spectroscopies. X-ray crystallography reveals tetrahedral geometries for Ph₃Sn(CH₂)₄ OC₆H₄C₆H₅ and Ph₃ Sn(CH₂)₃OC₆H₄C₆ H₄CN, a six-coordinated, bromine-bridged dimeric structure for PhBr₂Sn(CH₂)₃OC₆ H₄C₆H₅ containing a mer-Br₃ C₂OSn coordination sphere about tin and a five-coordinated monomeric structure for PhBr₂Sn(CH₂)₃ OC₆H₄C₆H₄CN. In all cases there is strong alignment of mesogenic groups in the solid-state but only PhBr₂Sn(CH₂)₃OC₆ H₄C₆H₄CN shows any indication of liquid-crystal behaviour. Wurtz polymerisation of RBr₂ Sn(CH₂)₅OC₆H₄C₆ H₅ (R=Ph, Bu), both of which contain non-chelating ether functions, generated polystannanes (RR′Sn)_n with M_n 2.3×10⁵; M_w 3.0× 10⁵; M_w/M_n 1.30 and M_n 1.3×10⁵; M_w 2.5×10⁵; M_w/M_n 1.96, respectively, while no polymer was obtained from chelated PhBr₂Sn(CH₂)₃ OC₆H₄C₆H₅

Full text of DOI:10.1016/j.jorganchem.2003.08.003

Journal of Organometallic Chemistry 687 (2003) 46ꢂ56
/
www.elsevier.com/locate/jorganchem
Organotin compounds bearing mesogenic sidechains: synthesis, X-ray
structures and polymerisation chemistry
P.R. Deacon, N. Devylder, M.S. Hill 1, M.F. Mahon, K.C. Molloy *, G.J. Price
Department of Chemistry, University of Bath, Bath BA2 7AY, UK
Received 1 July 2003; received in revised form 5 August 2003; accepted 13 August 2003
Abstract
Organotin compounds R3Sn(CH2)nꢀ2OC6H4C6H4Y (R3ꢁ
(RꢁPh, Bu; YꢁH, CN; XꢁBr, I; nꢁ1ꢂ
3) have been synthesised and characterised by H-, 13C-, 119Sn-NMR and Mossbauer
spectroscopies. X-ray crystallography and
/
Ph3, Ph2Bu; Yꢁ
/
H, CN; nꢁ
/
1ꢂ3) and RX2Sn(CH2)nꢀ2OC6H4C6H4Y
/
1
/
/
/
/
/
¨
reveals
tetrahedral
geometries
for
Ph3Sn(CH2)4OC6H4C6H5
Ph3Sn(CH2)3OC6H4C6H4CN, a six-coordinated, bromine-bridged dimeric structure for PhBr2Sn(CH2)3OC6H4C6H5 containing a
mer-Br3C2OSn coordination sphere about tin and a five-coordinated monomeric structure for PhBr2Sn(CH2)3OC6H4C6H4CN. In
all cases there is strong alignment of mesogenic groups in the solid-state but only PhBr2Sn(CH2)3OC6H4C6H4CN shows any
indication of liquid-crystal behaviour. Wurtz polymerisation of RBr2Sn(CH2)5OC6H4C6H5 (Rꢁ
non-chelating ether functions, generated polystannanes (RR?Sn)n with Mn 2.3ꢃ
105; Mw 3.0ꢃ105; Mw/Mn 1.30 and Mn 1.3ꢃ
Mw 2.5ꢃ
105; Mw/Mn 1.96, respectively, while no polymer was obtained from chelated PhBr2Sn(CH2)3OC6H4C6H5
# 2003 Elsevier B.V. All rights reserved.
/
Ph, Bu), both of which contain
/
/
/
105;
/
Keywords: Tin; Mesogen; X-ray; Mossbauer; Polymer
¨
1. Introduction
Central to the interest in these Group 14 homopoly-
mers are their optical and electronic properties, which
The synthesis and materials properties of catenated
show optical sꢂ
/
s* bandgaps in the range 300ꢂ
/
430 nm
Group 14 polymers (R2M)n (Mꢁ
to be a fertile area of chemical investigation [1ꢂ
the MꢂM bond energy decreases down the group so also
/Si, Ge, Sn) continues
as a result of delocalisation of s-electrons along the Mn
backbone. The larger, more diffuse Sn atomic orbitals
enhance s-delocalisation and hence these polymers
/
5]. As
/
show bandgaps ꢀ390 nm [1,2,4], some 70 nm or more
/
does the ease of polymer formation, achievable chain
length and polymer photostability tends to decrease,
making the poly-(diorganostannanes) the Cinderellas of
the triad. Synthetic methods for achieving relatively high
molecular weight (R2Sn)n have evolved from conven-
red-shifted from their better known poly-(diorganosi-
lane) analogues [11]. There have been several attempts
to reduce further the bandgap in poly-(diorganostan-
nanes), focussing on one of two approaches. Firstly, the
use of aromatic substituents on tin affords some sꢂ
delocalisation from the polymer backbone to the side-
chain and the bandgap for H[(o-Et-
p-nBuOC6H3)2Sn]nH (2.3 eV; 550 nm), some 30ꢂ
40
nm red-shifted with respect to the poly-dialkylstannanes
(R2Sn)n (RꢁnHex, nOct), is the lowest yet reported
/
p
tional Wurtz reduction (R2SnCl2ꢂ
dehydrogenative coupling of R2SnH2 monomers pro-
moted by a variety of transition metal catalysts [2,6ꢂ8].
Electrochemical methods [9] and reduction using SmI2
have also been reported in recent years [10].
/
Na) [3] to milder
/
/
/
[12]. Secondly, the conformation of the polymer back-
bone can also influence the bandgap, which reduces as
the contribution of planar, zigzag sections of the Mn
* Corresponding author. Tel.: ꢀ
386-231.
E-mail address: chskcm@bath.ac.uk (K.C. Molloy).
/
44-1225-386-382; fax: ꢀ44-1225-
/
chain increases [13ꢂ15]. This conformational ordering
/
1
can be induced by appropriate alignment of the side-
chain substituents, and was first noticed in the case of
Present address: Department of Chemistry, Imperial College,
South Kensington, London SW7 2AZ, UK.
0022-328X/03/$ - see front matter # 2003 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2003.08.003

P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ
/56
47
[(nHex)2Si]n [15] which shows a thermochromic shift in
the sꢂs* transition from 374 nm in an ordered film to
317 nm when the same film is heated to 100 8C [15].
Similar effects have been noted in the case of poly-
stannanes [1,2,16].
from the excess alkene is easily achieved by column
chromatography (SiO2, eluent gradient 60-80 petroleum
/
etherꢂ
Products 5ꢂ
colourless crystalline solids melting in the range 65ꢂ
/CH2Cl2).
/
9 were produced in 53ꢂ90% yield as
/
/
Our interest in the synthesis of poly-(diorganostan-
nanes) [3] has prompted us to explore the possibility of
forming polymers in which mesogenic substituents on
tin are used to influence the tertiary structure of the
polymer. The deployment of liquid-crystal sidechains is
not new in polymer chemistry and numerous examples
exist which reflect the important applications of such
117 8C, save for 9 which was a waxy solid; all
compounds were soluble in common organic solvents.
Cleavage of the Snꢂ
afforded the mixed diorganotin dihalides RR?SnX2 10ꢂ
14 in 43ꢂ88% yield. In the case of 14, the SnꢂPh bonds
were cleaved in preference to the SnꢂBu bonds, in line
with established protocols [20,21].
/
Ph bonds with halogen (Br2, I2)
/
/
/
/
materials in opto-electronic devices [17ꢂ
initial step in this direction, we now report the synthesis
and structural chemistry of R3Sn(CH2)nꢀ2OC6H4-
/
19]. As an
All compounds 1ꢂ14 gave satisfactory microanalyses;
/
1H- and 13C-NMR confirm the composition of the
products but are otherwise unexceptional (see Section
3).
C6H3Y (R3ꢁ
RX2Sn(CH2)nOC6H4C6H3Y (Rꢁ
XꢁBr, I; nꢁ1ꢂ3), along with preliminary observations
/
Ph3, Ph2Bu; Yꢁ
/
H, CN; nꢁ
/
1ꢂ/3) and
/
Ph, Bu; Yꢁ
/H, CN;
/
/
/
2.2. Structural studies
on the attempted polymerisation via Wurtz coupling of
these latter monomers. The liquid-crystal properties of
these compounds have been briefly explored.
The structures of the two unsymmetrical tetraorga-
notins 6, 8 are unexceptional (Figs. 1 and 3). The
geometry about each tin is tetrahedral, with bond angles
at tin in the range 105ꢂ
/
1138. This is consistent with their
singlet Mossbauer spectra and 119Sn-NMR chemical
2. Results and discussion
¨
shifts (ꢄ
/
101.2, ꢄ100.4 ppm, respectively) [22,23]. In
/
2.1. Synthesis
the lattice of 6, there is a head-to-tail alignment of
molecules such that the biphenyloxybutyl- ligands run
parallel to each other (Fig. 2). The greater polarity of 8
resulting from the incorporation of the nitrile group at
the extremity of the 4-cyanobiphenyloxypropyl-ligand
has a marked effect on the lattice packing, and a more
extensive alignment of mesogenic molecules is observed
in a distinctive herringbone arrangement (Fig. 4).
We have synthesised a series of tetraorganotin com-
pounds 5ꢂ/9 in which one of the organic groups [4-
YC6H4C6H4O(CH2)nꢀ2: Yꢁ
/
H, nꢁ1ꢂ3; YꢁCN, nꢁ
/
/
/
/
1] has the potential to induce liquid-crystal (LC)
ordering of molecules. The synthetic methodology is
shown in Scheme 1 and involves the hydrostannation of
a [4-biphenyloxy]-1-alkene 1-4 using a 2:1 ratio of alkene
to triorganotin hydride. In 1:1 stoichiometry significant
amounts of hexaorganoditin are produced, reducing the
PhBr2Sn(CH2)3OC6H4C6H4 (10) adopts a dimeric
structure (Fig. 5) in which the two halves of the dimer
are linked by weak intermolecular Br(1)Á Á ÁSn(1?) bridges
˚
overall yield of the desired R3SnR?. Separation of 5ꢂ
/
9
[4.318(1) A; ꢀ
/
Sn(1)ꢂ
/
Br(1)ꢂSn(1?): 93.13(2)8]. Chela-
/
Scheme 1.

48
P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ56
/
Fig. 1. The structure of 6 showing the labelling scheme; thermal ellipsoids are at the 30% level. Selected geometric data: Sn(1)ꢂ
/
C(1) 2.140(12), Sn(1)ꢂ
/
˚
C(7) 2.142(11), Sn(1)ꢂ
/
C(13) 2.143(13), Sn(1)ꢂ
/
C(19) 2.147(13) A; C(1)ꢂ
/
Sn(1)ꢂ
/
C(13) 105.8(5), C(1)ꢂ
/
Sn(1)ꢂ
/
C(7) 107.2(5), C(13)ꢂSn(1)ꢂC(7)
/
/
108.1(5), C(1)ꢂSn(1)ꢂC(19) 112.3(5), C(13)ꢂ
/
/
/
Sn(1)ꢂ
/
C(19) 110.9(5), C(7)ꢂSn(1)ꢂ
/
/C(19) 112.3(5)8.
the first crystallographically authenticated example of a
Br3C2O coordination sphere about tin. The chelating
O:0/Sn interaction is relatively weak, though such
bonds are easily influenced by both coordination
number and the Lewis acidity of the tin. In general,
for di-organontin species with CNꢁ
/
6 the dative O:0
/
˚
Sn bond is longer (e.g. 2.540ꢂ2.667 A) [24,25] than when
/
˚
5 (e.g. 2.382ꢂ2.448 A) [26], though in cases where
the acidity of tin is increased by the presence of
CNꢁ
/
/
additional electronegative atoms, chelation is enhanced
˚
Sn: 2.442 A
e.g. Cl3(H2O)Sn(CH2)3O(CH2)3OMe, O:0
/
[24]. In the lattice, columns of dimers of 10 are separated
from each other by columns of mesogenic biphenylox-
ypropyl-groups (Fig. 6).
Remarkably, when the substituent most remote from
Fig. 2. The unit cell of 6 viewed along b showing the alignment of the
biphenylether units.
tin on the biphenyl group is changed from Yꢁ
/
H (10) to
YꢁCN (12) (Scheme 1), the dimeric nature of the
complex changes to that of a monomer (Fig. 7). The
decreased Lewis acidity at tin in 12 is also manifested in
/
˚
tion by the ether oxygen [O(1)Á Á ÁSn(1): 2.734(4) A]
completes an octahedral coordination sphere about the
metal in which the three halogens are in a mer-
arrangement while the two carbon atoms are mutually
trans- to each other. To the best of our knowledge this is
an extremely weak O:0
/
Sn interaction [O(1)Á Á ÁSn(1):
2.918(7) A], though the approach of O(1) trans to Br1)
[ꢀO(1)ꢂSn(1)ꢂBr(1): 169.0(1)8] is such that the co-
˚
/
/
/
Fig. 3. The structure of 8 showing the labelling scheme; thermal ellipsoids are at the 30% level. Selected geometric data: Sn(1)ꢂ
/
C(1) 2.144(3), Sn(1)ꢂ
/
˚
C(7) 2.146(3), Sn(1)ꢂ
/
C(13) 2.133(3), Sn(1)ꢂ
/
C(19) 2.146(3) A; C(13)ꢂ
/
Sn(1)ꢂ/C(1) 106.19(12), C(13)ꢂ/Sn(1)ꢂ/C(7) 109.64(11), C(1)ꢂSn(1)ꢂC(7)
/
/
110.29(11), C(13)ꢂSn(1)ꢂ
/
/
C(19) 111.37(12), C(1)ꢂ
/
Sn(1)ꢂC(19) 110.49(13), C(7)ꢂ
/
/
Sn(1)ꢂC(19) 108.84(13)8.
/

P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ
/56
49
structure of 12 in the solid-state. There is no reason to
believe that dissolution would disrupt the intramolecu-
lar chelation by the phenyoxypropyl group in either
compound, while the weak BrÁ Á ÁSn bridges in 10 would
be susceptible to rupture in solution. The weakness of
the BrÁ Á ÁSn bridging interactions is also manifested in
the Mossbauer q.s. data, which are virtually identical for
¨
the two species (3.14, 3.17 mmsꢄ1, respectively), despite
the absence of such dimer formation in 12. Both of 11
and 14 appear to be tetrahedral in solution from their
downfield 119Sn-NMR chemical shifts (3.5, 88.6 ppm),
while 13 also fits into this category as it has d(19Sn) of
ꢄ/157.2 ppm, which is comparable with that of Me2SnI2
(ꢄ157 ppm) [27]. In each case this rules out intramo-
/
lecular chelation by the phenyloxypentyl moiety, which
is not unreasonable as it would require formation of a
seven-membered ring. This lack of intramolecular
chelation is also reflected in the solid state, where both
Fig. 4. The unit cell of 8 viewed along b showing the alignment of the
biphenylether units and the herringbone packing.
11 and 13 show reduced Mossbauer q.s. values (2.73,
¨
2.57 mmsꢄ1, respectively), typical of four-coordinate
tin. The q.s. exhibited by 14 (3.35 mm sꢄ1) could,
however, indicate some ordering of molecules in the
solid-state. Et2SnBr2 has a q.s. of 3.54 mm sꢄ1 [28] and
whose X-ray structure reveals a linear array of mole-
ordination sphere about tin is best described as trigonal
bipyramidal. In the lattice, despite the monomeric
nature of 12 the molecules organise themselves into
parallel head-to-tail stacks such that the pairs of Br2Sn
moieties are to the interior, sheathed by columns of
highly aligned mesogenic 4?-cyanobiphenyloxypropyl
ligands (Fig. 8).
In the light of the above structures, the spectroscopic
data for the remaining compounds synthesised can be
analysed with some confidence. The remaining R3SnR?
compounds 5, 7, 9 are tetrahedral at tin, as evidenced by
˚
cules linked by pairs of BrÁ Á ÁSn bridges [3.777(4) A] [29].
Of the compounds investigated, only 12 showed the
possibility of an intermediate phase transition, in addi-
tion to the melting point, in a DSC analysis. That the
compounds lacking a terminal ꢂCN did not form liquid
/
crystals is not surprising given the additional polarity
that is often needed to enhance intermolecular interac-
tions. In comparing 12 with 8, the lack of mesogenic
behaviour in the latter may be due to the larger triphenyl
headgroup preventing a sufficiently close approach of
the cyanobiphenyl tails. Further work is needed to fully
characterise potentially mesogenic behaviour in these
compounds as well as the nature of any mesophase.
singlet Mossbauer spectra (i.s.ꢁ
/
1.27ꢂ
and 119Sn chemical shifts corresponding to four-coordi-
nate tin (dꢁ 100.1, ꢄ100.4, ꢄ72.3 ppm, respec-
tively). The NMR data for 10 (ꢄ53.3 ppm) and 12
(ꢄ47.6 ppm) clearly represent a common structural
motif in solution, and this will be the same as the
/
1.31 mm sꢄ1
)
¨
/
ꢄ
/
/
/
/
/
Fig. 5. The dimeric structure of 10 showing the labelling scheme; thermal ellipsoids are at the 30% level. Selected geometric data: Sn(1)ꢂ
/
C(1)
C(7)
˚
2.105(6), Sn(1)ꢂ
137.4(2), C(1)ꢂSn(1)ꢂ
C(7)ꢂSn(1)ꢂBr(1) 99.9(2), C(7)ꢂ
Sn(1)ꢂBr(1?) 87.11(9), Br(2)ꢂSn(1)ꢂ
/
C(7) 2.120(6), Sn(1)ꢂ
O(1) 83.4(2), C(1)ꢂ
Sn(1)ꢂBr(2) 105.6(2), C(7)ꢂ
Br(1) 100.56(3), Br(1)ꢂSn(1)ꢂ
/
Br(1) 2.5449(9), Sn(1)ꢂ
Sn(1)ꢂBr(1) 100.7(2), C(1)ꢂ
Sn(1)ꢂBr(1?) 60.8(2), Br(1)ꢂ
Br(1?) 86.86(3), Br(2)ꢂSn(1)ꢂ
/
Br(2) 2.4906(9), Sn(1)ꢂ
Sn(1)ꢂBr(2) 106.7(2), C(1)ꢂ
Sn(1)ꢂO1 172.33(9), Br(2)ꢂ
Br(1?) 165.75(3)8.
/
O(1) 2.734(4), Sn(1)ꢂ
Sn(1)ꢂBr(1?) 83.6(2), C(7)ꢂ
Sn(1)ꢂO(1) 84.38(9), O(1)ꢂ
/
Br(1?) 4.318(1) A; C(1)ꢂ
/
Sn(1)ꢂ
/
/
/
/
/
/
/
/
/
/Sn(1)ꢂ/O(1) 72.9(2),
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/

50
P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ56
/
this additional chelation will presumably add steric
hindrance and hence may explain the lack of reaction.
In contrast, both 11 and 14 incorporate pentylether
groups which do not participate in intramolecular
chelation to the tin. It would appear that a coordination
number for tin of four in solution is a requirement for
the reaction to proceed. GPC of the extremely light-
sensitive polystannanes in toluene yielded a higher
average molecular weight material (polystyrene equiva-
lent) from 11 (Mn 2.3ꢃ
polydispersity (Mw/Mn 1.30) than polymer derived from
14 (Mn 1.3 ꢃ
105; Mw 2.5ꢃ105; Mw/Mn 1.96). In
/
105; Mw 3.0ꢃ
/
105) and lower
/
/
addition, a higher proportion of low molecular weight
material (cyclic oligomers Sn5,6 of mass up to ca. 1000
amu) was noted from reaction of 14 (polymer: cyclics
ca. 1:4) than in the case of 11 (ca. 1:1). By analogy with
the reaction in silicon based chains, low molar mass
material results from a back-biting reaction at the
surface so that again the steric influence of Ph or Bu
groups at tin may influence the relative efficiency of the
chain propagation versus cyclisation. It was recently
shown [31] that the molecular weight and bimodality of
the polymer fraction is heavily influenced by the
optimum chain length for a stable backbone conforma-
tion to form, so that again steric factors as well as the
electronic influence of the metal substituent on the s
conjugation may play a part. However, it should be
stressed that these are preliminary conclusions and
further work on a range of systems is needed to fully
elucidate these effects.
Fig. 6. Unit cell of 10.
2.3. Polymerisation reactions
Solutions of diorganotin dihalides 10, 11 and 14 in
toluene were treated, in the dark, with Na/15-crown-5 to
effect Wurtz coupling, using a protocol which we have
found capable of generating poly(organostannes) of
very high molecular weight [3]. The key to controlling
the Wurtz coupling is the reaction time, since degrada-
tion of the polymer takes place with time. Under these
conditions, both 11 and 14 gave brown, polymeric
(RR?Sn)n, while no high molecular weight material
was generated by 10. The failure of 10 to polymerise
under Wurtz conditions is possibly due to its structure,
which in solution is five-coordinate at tin as a result of
the chelating propylether functionality. Since Wurtz-
type polymerisation occurs at the surface of sodium [30],
Disappointingly, the uv spectra of the polymers
generated from 11 and 14 showed intense (o Â
/
20,000
dm3 molꢄ1 cmꢄ1) lmax at 255 nm due to the mesogen,
Fig. 7. The structure of 12 showing the labelling scheme; thermal ellipsoids are at the 30% level. Selected geometric data: Sn(1)ꢂ
/
C(1) 2.126(10),
Sn(1)ꢂBr(1) 107.8(3),
Sn(1)ꢂO(1) 66.7(3), Br(1)ꢂ
˚
Sn(1)ꢂ
C(1)ꢂSn(1)ꢂ
Sn(1)ꢂBr(2) 97.72(6), Br(1)ꢂ
/
C(7) 2.136(11), Sn(1)ꢂ
Br(2) 103.6(3), C(1)ꢂ
Sn(1)ꢂ
/
Br(1) 2.515(2), Sn(1)ꢂ
Sn(1)ꢂO(1) 81.3(3), C(7)ꢂ
O(1) 169.0(1), Br(2)ꢂSn(1)ꢂ
/
Br(2) 2.509(2), Sn(1)ꢂ
Sn(1)ꢂBr(1) 102.3(3), C(7)ꢂ
O(1) 85.9(2)8.
/
O(1) 2.918(7) A; C(1)ꢂ
/
Sn(1)ꢂ
/
C(7) 132.7(5), C(1)ꢂ
/
/
/
/
/
/
/
/
/
Sn(1)ꢂBr(2) 107.6(4), C(7)ꢂ
/
/
/
/
/
/
/
/
/

P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ
/56
51
potassium iodide were dissolved in a mixture of
ethanolꢂwater (4:1) (440 ml). 3-Bromopropene (9 ml,
/
100 mmol) was added to the resulting solution which
was then refluxed for 5 h. Removal of solvent in vacuo
resulted in a pure white solid. This was dissolved in
CH2Cl2 and filtered through a Celite column to remove
KBr. Removal of solvent yielded (1) as a colourless
crystalline solid (18.3 g, 87%) m.p. 68 8C. Anal. Found
(Calc. for C15H14O): C, 85.5 (85.7); H, 6.72 (6.67)%. 1H-
NMR: 4.52 (d, 2H, CH2); 5.27 (d, 1H, trans-CH); 5.40
(d, 1H, cis-CH); 6.04 (m, 1H, ꢁ
C6H4O); 7.20ꢂ
7.60(m, 7H, Haryl). 13C-NMR: 68.8
(CH2); 115.0 (o-C6H4O); 115.6 (ꢁCH); 117.6 (ꢁCH2);
/CH); 6.95 (d, 2H, o-
/
/
/
126.6 (p-C6H5); 126.7 (m-C6H4O); 128.0 (o-C6H5);
128.7 (m-C6H5); 133.8 (i-C6H5); 140.7 (i-C6H4); 158.1
(i-C6H4O). IR (Nujol): 2955, 2855, 1606, 1522, 1379,
1290, 1271, 1254, 1120, 989, 925, 833, 763, 696.
Fig. 8. The unit cell of 12 viewed along b.
tailing off at l ꢀ310 nm. No absorbances due to
/
3.2. Synthesis of 4-(4-biphenylphenoxy)-1-butene (2)
polymeric material at l ꢀ380 nm were observable.
/
This compound was synthesised via a similar method
to 1, employing 4-hydroxybiphenyl (12.61 g, 74 mmol),
potassium hydroxide (4.16 g, 74 mmol) and 4-bromo-1-
3. Experimental
butene (10.0 g, 74 mmol) in ethanolꢂwater (4:1) (400
/
Infrared spectra (cmꢄ1) were recorded between NaCl
plates using a Nicolet 510P FT-IR spectrometer, while
ml). A similar work-up procedure yielded 2 as colourless
crystals (13.5 g, 81%). m.p. 77 8C. Anal. Found (Calc.
for C16H16O): C, 85.4 (85.7); H, 7.15 (7.14)%. 1H-NMR:
elemental analyses were performed using an CarloꢂErba
/
Strumentazione E.A. model 1106 microanalyser operat-
1
2.54 (m, 2H, CH2CHꢁ
2H, ꢁCH2); 5.90 (m, 1H, ꢁ
7.26ꢂ
7.55 (m, 7H, Haryl). 13C-NMR: 33.7 (CH2CHꢁ
67.3 (CH2O); 114.9 (o-C6H4O); 115.6 (CHꢁCH2); 117.0
(ꢁCH2); 126.6 (m-C6H4O); 126.7 (p-C6H5Ar); 128.1 (o-
/
); 4.00 (t, 2H, CH2O); 5.13 (m,
CH); 6.95 (d, 2H, o-C6H4O);
);
ing at 500 8C. H- and 13C-NMR spectra were recorded
/
/
on a JEOL JNM-GX270 FT spectrometer and 119Sn-
NMR spectra were recorded on A JEOL JNM-EX400
FT spectrometer, all using saturated CDCl3 solutions
unless indicated otherwise; chemical shifts are in ppm
with respect to either Me4Si or Me4Sn, coupling
constants in Hz. Differential scanning calorimetery
(DSC) was carried out on a TA instruments 2910
calorimeter using aluminium pans with an empty pan
of equal mass used as the reference. Calibration was
achieved by comparison with authentic liquid crystalline
materials (M24 from Merck Ltd.). Details of our
/
/
/
/
C6H5Ar); 128.7 (m-C6H5Ar); 133.8 (i-C6H5Ar); 140.8
(i-C6H4Ph); 158.5 (i-C6H4O). IR (Nujol): 2924, 2853,
1608, 1522, 1489, 1377, 1288, 1269, 1245, 1033, 833, 760,
688.
3.3. Synthesis of 5-(4-biphenylphenoxy)-1-pentene (3)
This compound was synthesised via a similar method
employing 4-hydroxybiphenyl (6.16 g, 36 mmol), potas-
sium hydroxide (2.00 g, 36 mmol) and 5-bromopentene
Mossbauer spectrometer and related procedures are
¨
given elsewhere [32]; data are in mm sꢄ1. Dry solvents
were obtained by distillation under inert atmosphere
from the following drying agents: sodium-benzophe-
none (toluene, ether, THF), calcium hydride (CH2Cl2),
sodium (hexane). Standard Schlenk techniques were
used throughout. Starting materials were commercially
obtained and used without further purification.
Ph3SnBu was prepared from Ph3SnCl and BuMgCl
(5.36 g, 36 mmol) in ethanolꢂwater (4:1) (200 ml). A
/
similar work-up procedure yielded (3) as colourless
crystals (6.3g. 74%) m.p. 60 8C. Anal. Found (Calc.
for C17H18O): C, 85.2 (85.7); H, 7.55 (7.56)%. 1H-NMR:
1.86 (m, 2H, CH2); 2.22 (m, 2H, ꢁ
CH2O); 5.00 (d, 1H, trans-ꢁCH); 5.05 (d, 1H, cis-ꢁ
5.83 (m, 1H, ꢁCH); 6.92 (d, 2H, o-C6H4O); 7.20ꢂ
(m, 7H,Haryl). 13C-NMR: 28.3 (CH2); 30.1 (CH2); 67.2
(CH2O); 114.8 (o-C6H4O); 114.9 (HCꢁ); 117.5 (ꢁCH2);
/
CHCH2; 3.94 (t, 2H,
CH);
7.60
/
/
/
/
following literature methodology [d(119Sn): ꢄ
100.1
/
ppm] [33].
/
/
126.5 (m-C6H4O); 126.6 (p-C6H5); 128.0 (o-C6H4);
128.6 (m-C6H5); 133.5 (i-C6H5); 140.8 (i-C6H4); 158.6
(i-C6H4O). IR (Nujol): 2924, 2855, 1643, 1608, 1522,
1489, 1377, 1286, 1271, 1201, 1074, 1039, 1022, 908, 827,
758, 71 l, 688.
3.1. Synthesis of 3-(4-biphenyloxy)-1-propene (1)
4-Hydroxybiphenyl (17.0 g, 100 mmol), potassium
hydroxide (5.61 g, 100 mmol) and a few crystals of

52
P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ56
/
3.4. Synthesis of 3-(4?-cyano-4-biphenylphenoxy)-1-
propene (4)
4H, CH2CH2CH2CH2); 3.95 (t, 2H, CH2O); 6.90 (d, 2H,
o-C6H4O); 7.27ꢂ
7.60 (m, 22H, Haryl). 13C-NMR: 10.6
/
(CH2Sn); 23.2 (CH2CH2Sn); 33.6 (CH2(CH2)2Sn); 67.2
(CH2O); 114.7 (o-C6H4O); 126.6 (m-C6H4O); 128.1 (o-
C6H5); 128.5 (m-C6H5Sn); 128.7 (o-C6H5); 128.9 (p-
C6H5Sn); 133.5 (i-C6H5); 137.0 (o-C6H5Sn); 137.2 (p-
C6H5); 138.8 (i-C6H5Sn); 140.9 (i-C6H4); 158.6 (i-
This compound was prepared in an analogous fashion
from 4?-hydroxy-4-biphenylcarbonitrile (4.00 g, 21
mmol), potassium hydroxide (1.10 g, 21 mmol) and
allyl bromide (3.00 g, 2.4 mmol) in isopropyl alcohol
(100 ml). Recrystallisation from ethanol yielded 4 as
yellow cubic crystals (4.00 g, 80%) m.p. 71 8C. The
identical procedure performed in ethanol gave no
reaction. Anal. Found (Calc. for C16H13NO): C, 81.3
C6H4O). 119Sn-NMR:
ꢄ
/
101.2. 119mSn Mossbauer
¨
(mm sꢄ1): i.s.ꢁ
2926, 2856, 1520, 1423, 1377, 1286, 1251, 1074, 997, 836,
753, 731, 700, 659.
/
1.26; q.s.ꢁ
/
0.0; Gꢁ0.96. IR (Nujol):
/
1
(81.7); H, 5.80 (5.53); N, 5.95 (5.95)%. H-NMR: 4.58
(d, 2H, CH2O); 5.32 (dd, 1H, trans-ꢁ
cis-CH); 6.08 (m, 1H, CH ꢁCH2); 7.01 (d, 2H, o-
C6N4O); 7.50ꢂ
7.70 (m, 6H, Haryl). 13C-NMR: 68.8
(CH2O); 110.0 (CN); 115.3 (HCꢁ, o-C6N4O); 117.8 (ꢁ
/
CH); 5.44 (dd, 1H,
/
3.7. Synthesis of triphenyl[5-(4-biphenyloxy)pentyl]tin
(7)
/
/
/
CH2); 119.0 (i-C6H4CN); 127.0 (m-C6N4O); 128.2 (o-
C6H4CN); 131.5 (i-C6H4C6N4O); 132.5 (m-C6H4CN);
145.1 (i-C6H4CN); 159.1 (i-C6N4O). IR (Nujol): 2924,
2222, 1604, 1518, 1466, 1377, 1290, 1248, 1178, 1116,
995, 841, 852, 823, 563, 534.
Preparation and isolation as for 5 using triphenyltin
hydride (2.91 g, 8.3 mmol) and 3 (4.18 g, 16.6 mmol)
yielded 7 as a colourless crystalline solid (4.20 g, 84%)
m.p. 86 8C. Anal. Found (Calc. for C35H34OSn): C, 70.5
(71.3); H, 5.88 (5.78)%. 1H-NMR [d(ppm), CDCl3]: 1.54
(m, 4H, CH2CH2Sn); 1.78 (m, 4H, CH2CH2CH2O); 3.78
(t, 2H, CH2O); 6.88 (d, 2H, o-C6H4O); 7.28-7.60 (m,
22H, Haryl). 13C-NMR [d(ppm), CDCl3]: 10.9 (CH2Sn,
3.5. Synthesis of triphenyl[3-(4-biphenyloxy)propyl]tin
(5)
1Jꢁ
367, 395 Hz); 26.4 (CH2CH2Sn); 28.7
/
Triphenyltin hydride (1.67 g, 4.8 mmol) and 1 (2.00 g,
9.5 mmol) were heated as a melt with ca. 50 mg AIBN to
140 8C under nitrogen for 1 h; the mixture solidified to a
grey mass on cooling. Column chromatography on SiO2
(CH2(CH2)2Sn); 30.6 (CH2CH2O); 67.8 (CH2O); 114.7
(o-C6H4O); 126.6 (m-C6H4O); 126.7 (p-C6H5); 128.0 (o-
C6H5); 128.5 (m-C6H5Sn); 128.7 (m-C6H5); 128.8 (p-
C6H5Sn); 133.5 (i-C6H5); 137.0 (o-C6H5Sn); 138.9 (i-
C6H5Sn); 140.8 (i-C6H4); 158.6 (i-C6H4O); 119Sn-NMR
employing a gradient of 60-80 petroleum etherꢂCH2Cl2
/
as elutant yielded 5 as a colourless crystalline solid (2.4
[d(ppm), CDCl3]:ꢄ
/
100.4. 119mSn Mossbauer (mmsꢄ1):
¨
g, 90%) m.p. 74 8C. Anal. Found (Calc. for C33H30OSn):
C, 70.1 (70.6); H, 5.35 (5.35)%. H-NMR: 1.63 (t, 2H,
CH2Sn); 2.20 (m, 2H, CH2CH2CH2); 3.96 (t, 2H,
I.S.ꢁ1.27; Q.S.ꢁ0.0; Gꢁ0.99. IR (KBr): 3061, 2936,
/
/
/
1
2869, 1605, 1520, 1487, 1473, 1427, 1286, 1269, 1248,
1198, 1074, 1041, 761, 731, 698, 447.
CH2O); 6.82 (d, 2H, o-C6H4O); 7.25ꢂ
/
7.65 (m, 22H,
aryl). 13C-NMR: 6.9 (CH2Sn); 26.3(CH2CH2Sn); 70.6
H
(CH2O); 114.7 (o-C6H4O); 126.6 (m-C6H4O); 128.0 (o-
C6H5); 128.5 (m-C6H5Sn); 128.7 (m-C6H5); 128.9 (p-
C6H5Sn); 133.6 (i-C6H5); 137.0 (o-C6H5Sn); 137.4 (p-
C6H5); 138.6 (i-C6H5Sn); 140.8 (i-C6H4); 158.5 (i-
3.8. Synthesis of triphenyl[4-(4?-cyano-4-biphenyloxy)
propyl]tin (8)
C6H4O); 119Sn-NMR:
ꢄ
/
100.1. 1l9mSn Mossbauer
Preparation and isolation as for 5 using triphenyltin
hydride (0.75 g, 2.13 mmol) and 4 (1.00 g, 4.25 mmol)
yielded 8 as a colourless crystalline solid (0.80 g, 66%)
m.p. 117 8C. Anal. Found (Calc. for C34H29NOSn): C,
¨
(mmsꢄ1): i.s.ꢁ
/
1.26; q.s.ꢁ
/
0.0; Gꢁ0.98. IR (KBr):
/
3059, 2915, 2853, 1605, 1585, 1520, 1491, 1464, 1427,
1387, 1290, 1269, 1248, 1190, 1176, 1147, 1072, 1022,
1012, 997, 893, 835, 758, 729, 694, 501, 457, 447.
1
69.3 (69.7); H, 4.79 (4.95); N, 2.42 (2.39)%. H-NMR:
1.70 (t, 2H, CH2Sn); 2.26 (m, 2H, CH2CH2O); 3.97 (t,
3.6. Synthesis of triphenyl[4-(4-biphenyloxy)butyl]tin
(6)
2H, CH2O); 6.85 (d, 2H,o-C6H4O); 7.34ꢂ
H
/
7.68 (m, 22H,
aryl). 13C-NMR: 6.8 (CH2Sn); 26.2 (CH2CH2Sn); 70.6
(CH2O); 110.0 (CN); 115.1 (o-C6H4O); 119.1 (i-
C6H4CN); 127.1 (m-C6H4O); 128.2 (o-C6H4CN); 128.5
(m-C6H5Sn); 128.9 (p-C6H5Sn); 131.3 (i-C6H4); 132.5
(m-C6H4CN); 137.0 (o-C6H5Sn); 138.5 (i-C6H5Sn);
Prepared as for 5 using triphenyltin hydride (3.15 g,
9.0 mmol) and (2) (4.10 g, 18.0 mmol).Column chro-
matography on SiO2 employing a gradient of 60-80
petroleum etherꢂ
/
CH2Cl2 as elutant yielded 6 as a
145.3 (i-C6H4); 159.5 (i-C6H4O). 119Sn-NMR:
100.4. 119mSn Mossbauer (mm sꢄ1): i.s.ꢁ
1.22; q.s.ꢁ
0.98. IR (Nujol): 2924, 2222, 1576, 1240, 1155,
1076, 972, 823, 727, 700.
ꢄ
/
colourless crystalline solid (3.00 g, 58%) m.p. 65 8C.
Anal. Found (Calc. for C34H32OSn): C, 70.7 (71.0); H,
1
5.64 (5.57)%. H-NMR: 1.56 (t, 2H, CH2Sn); 1.87 (m,
/
/
¨
0.0; Gꢁ
/

P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ
/56
53
3.9. Synthesis of diphenylbutyltin iodide
126.6 (m-C6H4O); 126.7 (p-C6H5); 128.1 (o-C6H5);
128.2 (m-C6H5Sn); 128.4 (m-C6H5); 128.7 (p-C6H5Sn);
133.5 (i-C6H5); 136.7 (o-C6H5Sn); 140.2 (i-C6H5Sn);
Iodine (6.24g, 48.0 mmol) in chloroform (600 ml) was
added dropwise over 2.5 h to a stirred solution of
Ph3BuSn (10.0 g, 24.6 mmol) in chloroform (100 ml) at
0 8C. Stirring was continued for 24 h giving a very pale
pink solution. This was evaporated to yield a brown oil
which upon distillation on a Kugelruhr appparatus gave
Ph2BuSnI as a colourless oil (9.4 g, 84%) b.p. 165 8C/
0.06 mmHg. Anal. Found (Calc. for C16H19ISn): C, 41.8
140.8 (i-C6H4); 158.6 (i-C6H4O). 119Sn: ꢄ
/
72.3. 119mSn
0.0; Gꢁ1.20.
Mossbauer (mm sꢄ1): i.s.ꢁ
/
1.31; q.s.ꢁ
/
/
¨
3.12. Synthesis of phenyl[3-(4-biphenyloxy)propyl]tin
dibromide (10)
A solution of bromine (0.74 g, 9.26 mmol) in chloro-
form (50 ml) was added dropwise at 0 8C to a solution of
5 (1.29 g, 2.3 mmol) in chloroform (50 ml). The resulting
colourless solution was stirred for 24 h at which point
the solvent was removed under vacuum to yield a yellow
oil. Prolonged pumping to remove bromobenzene
produced an oil which solidified on standing. Recrys-
1
(42.1); H, 4.09 (4.16)%. H-NMR: 0.98 (t, 3H, CH3);
1.84 (m, 4H,
1.48 (m, 2H, CH2CH2Sn); 1.65ꢂ
/
CH2CH2CH2Sn); 7.42ꢂ
/
7.74 (m, 15H, C6H5). 13C-
NMR: 13.5 (CH3); 17.0 (CH2Sn); 26.5 (CH2(CH2)2Sn);
28.8 (CH2CH2Sn); 128.8 (m-C6H5); 129.6 (p-C6H5);
136.0 (o-C6H5). 119Sn-NMR: ꢄ
/
53.0. 119mSn Mossbauer
(mm sꢄ1): i.s.ꢁ
/
1.41; q.s.ꢁ
/
2.46; Gꢁ1.05.
/
tallisation from petrolꢂchloroform yielded 10 as colour-
/
less crystals (1.10 g, 78%) m.p. 72 8C. Anal. Found
(Calc. for C21H20Br2OSn): C, 45.4 (44.5); H, 3.53
1
(3.53)%. H-NMR: 2.20 (m, 2H, CH2Sn); 2.36 (m, 2H,
3.10. Synthesis of diphenylbutyltin hydride
A solution of diphenylbutyltin iodide (8.68 g, 19.0
mmol) in diethyl ether (40 ml) was added slowly to a
suspension of LiAlH4 (0.72 g, 19.0 mmol) in diethyl
ether (30 ml) under nitrogen. The resulting suspension
was refluxed for 3 h and stirred at ambient temperature
for a further 18 h. Careful hydrolysis with a hydro-
quinone solution in water (0.1 g in 3 ml) resulted in a
grey suspension which was filtered and the filtrate
subsequently dried over magnesium sulphate. Filtration
and evaporation of the solvent yielded diphenylbutyltin
hydride as a yellow oil (4.25 g, 68%). Anal. Found (Calc.
for C16H20Sn): C, 58.7 (58.1); H, 5.21 (6.05)%. 1H-
CH2CH2CH2); 4.05 (t, 2H, CH2O); 6.63 (d, 2H, o-
C6H4O); 7.15ꢂ
7.55 (m, 12H, Haryl). 13C-NMR: 23.1
/
(CH2Sn); 25.7 (CH2CH2Sn); 69.6 (CH2O); 115.9(o-
C6H4O); 126.7 (m-C6H4O); 126.8 (p-C6H5); 127.8 (o-
C6H5); 128.7 (m-C6H5); 129.1 (p-C6H5Sn); 130.8 (m-
C6H5Sn); 134.7 (o-C6H5Sn); 135.0 (i-C6H5); 140.0 (i-
C6H5Sn); 140.4 (i-C6H4Ph); 156.9 (i-C6H4O). 119Sn-
NMR: -53.3. 119mSn Mossbauer (mm sꢄ1): i.s.ꢁ
/
1.53;
0.82. IR (KBr): 3054, 2948, 2907, 1601,
1485, 1471, 1431, 1408,
¨
q.s.ꢁ
/
3.14; Gꢁ
/
1585,
1520,
1381,1230,1197,1176, 1153, 1068, 999, 991, 908, 837,
765, 729, 729, 692, 446.
NMR: 0.90 (t, 3H,CH3); 1.38ꢂ
CH2CH2Sn); 1.68ꢂ1.81 (m, 4H, CH2CH2CH2Sn);
7.38ꢂ7.46 (m, 6H, m,p-C6H5Sn); 7.59ꢂ7.61 (m, 4H, o-
C6H5Sn). 13C-NMR: 13.5 (CH3); 17.4 (CH2Sn, 1Jꢁ
410,
/1.46 (m, 2H,
/
/
/
3.13. Synthesis of phenyl[5-(4-biphenyloxy)pentyl]tin
/
dibromide (11)
428 Hz); 26.7 (CH2(CH2)2Sn); 28.8 (CH2CH2Sn); 128.9
(m-C6H5Sn); 130.0 (p-C6H5Sn); 135.7 (o-C6H5Sn);
This compound was prepared via a similar method as
outlined above for 10 from bromine (3.32 g, 41.6 mmol)
in chloroform (250 ml) and 7 (6.12 g, 10.4 mmol).
Recrystallisation from 40-60 petrol yielded 11 as colour-
less crystals (5.40 g, 88%) m.p. 47 8C. Anal. Found
138.9 (i-C6H5Sn); 119Sn-NMR: 15.9. 119mSn Mossbauer
¨
(mm sꢄ1): i.s.ꢁ
film): 1832 [n(Snꢂ
/
1.30; q.s.ꢁ
/
0.00; Gꢁ1.26. IR (liquid
/
/H)].
3.11. Synthesis of diphenylbutyl[5-(4-biphenyloxy)
pentyl]tin (9)
(Calc. for C23H24Br2OSn): C, 46.0 (46.4); H, 4.00
1
(4.04)%. H-NMR: 1.61ꢂ
/
2.09 (m, 8H, (CH2)4Sn); 3.95
7.66(m,
aryl); 13C-NMR: 25.3 (CH2Sn); 26.1
(CH2CH2Sn); 28.6 (CH2(CH2)2Sn); 29.
(t, 2H, CH2O); 6.91 (d, 2H, o-C6H4O); 7.24ꢂ
/
Preparation and isolation as for 5 using diphenylbu-
tyltin hydride (4.24 g, 12.8 mmol) and 3 (6.10 g, 25.6
mmol) yielded 9 as an oil which solidified to a colourless
waxy solid on standing (3.8 g, 53%). Anal. Found (Calc.
12H,
H
3
(CH2(CH2)3Sn); 67.4 (CH2O); 114.7 (o-C6H4O); 126.6
(m-C6H4O); 128.0 (p-C6H5); 128.7 (o-C6H5); 129.4 m-
C6H5); 131.3(m-C6H5Sn); 133.6 (i-C6H5Ar); 134.5 (o-
C6H5Sn); 134.8 (p-C6H5Sn); 139.0 (i-C6H5Sn); 140.7 (i-
C6H4); 158.4 (i-C6H4O). 119Sn-NMR: 3.50. 119mSn
1
for C33H39OSn): C, 69.2 (69.6); H, 6.41 (6.68)%. H-
NMR: 0.87 (t, 3H, CH3); 1.25ꢂ1.80 (m, 14H, 7 CH2);
/
3.90 (t, 2H, CH2O); 6.90 (d, 2H, o-C6H4O); 7.24ꢂ7.54
/
(m, 17H, Haryl). 13C-NMR: 10.2 (CH2Sn); 10.5 (CH2Sn);
13.6 (CH3); 26.5 (CH2CH2Sn); 27.3 (CH2(CH2)2Sn);
Mossbauer (mm sꢄ1): i.s.ꢁ
/
1.41; q.s.ꢁ
/
2.73; Gꢁ0.93.
/
¨
IR (KBr): 2930, 2905, 2860, 1607, 1520, 1487, 1469,
1431, 1290, 1274, 1246, 1190, 1138, 1068, 995, 835, 765,
729, 692, 681.
28.7
(CH2CH2O);
28.9
(CH2CH2Sn);
(CH2CH2(CH2)2Sn); 67.9 (CH2O); 114.7 (o-C6H4O);
30.6

54
P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ56
/
3.14. Synthesis of phenyl[4-(4?-cyano-4-biphenyloxy)
propyl]tin dibromide (12)
67.5 (CH2O); 114.7 (o-C6H4O); 126.6 (m-C6H4O); 126.7
(p-C6H5); 128.1 (o-C6H5); 128.7 (m-C6H5); 133.7 (i-
C6H5); 140.8 (i-C6H4); 158.5 (i-C6H4O). 119Sn-NMR:
This compound was prepared in a manner analogous
to that of 10, using 8 (0.23 g, 0.4 mmol) and bromine
(0.13 g, 0.8 mmol) in dichloromethane (100 ml). After
removal of all volatiles in vacuo, the remaining solid was
88.6. 119mSn Mossbauer (mm sꢄ1): i.s.ꢁ
/
1.66; q.s.ꢁ
/
¨
0.94; IR (KBr): 2926, 1520, 1487, 1470, 1289,
3.35; Gꢁ
/
1251, 1176, 835, 763, 685, 601.
crystallised from 40ꢂ
/
60 petrolꢂCH2Cl2 (1:1) (0.15 g,
/
3.17. Polymerisations
65%) m.p. 96 8C, clearing point 142 8C. Anal. Found
(Calc. for C22H19Br2NOSn): C, 42.8 (44.6); H, 3.21
(3.21); N, 2.28 (2.37)%. 13C-NMR: 23.6 (CH2Sn); 25.7
(CH2CH2Sn); 69.4 (CH2O); 110.4 (CN); 116.0 (o-
The procedure used conditions optimised for the
Wurtz coupling of Bu2SnCl2 described elsewhere [3].
Typically, 0.5 g of either 10, 11 or 14 was dissolved in
toluene (10 ml) and treated with 15-crown-5 (0.1 ml) and
30% sodium dispersion in toluene (0.8 ml) in a nitrogen-
filled Schlenk tube, wrapped in foil to exclude light. The
resulting mixture was heated at 60 8C for 4 h, canula
filtered and the solvent removed in vacuo, again with
exclusion of ambient light. Any residual traces of
sodium were quenched by the addition of dry methanol
(5ml). The polymer was then isolated as a sticky brown
solid by solvent evaporation. Samples for GPC were
taken by dissolving the material in toluene and keeping
the solution in the dark and cooled until required for
analysis.
C6H4O); 119.0 (i-C6H4CN); 127.1ꢂ
158.1 (i-C6H4O). 119Sn-NMR: ꢄ47.6. 119mSn Moss-
bauer (mm sꢄ1): i.s.ꢁ
1.50; q.s.ꢁ
(KBr): n(CN) 2228.
/145.0 (m, aryl);
/
¨
/
/
3.17; Gꢁ0.98. IR
/
3.15. Synthesis of phenyl(5-(4-biphenyloxy)pentyl]tin
diiodide (13)
This compound was prepared via a similar method as
outlined above for 10 from iodine (2.16 g, 17.0 mmol) in
chloroform (250 ml) and 7 (2.50 g, 4.25 mmol).
Recrystallisation from 40-60 petrol yielded 13 as a pale
brown solid (1.40 g, 48%) m.p. 58 8C. Anal. Found
(Calc. for C23H24I2OSn): C, 40.0 (40.1); H, 3.49 (3.63)%.
1H-NMR: 1.63 (m, 2H, CH2(CH2)3Sn); 1.85 (m, 4H,
(CH2)2CH2Sn); 2.14 (t, 2H, CH2Sn); 3.97 (t, 2H,
3.18. X-ray crystallography
Experimental and crystallographic details are given in
Table 1. In each case data were collected at 293 K on an
CH2O); 6.94 (d, 2H, o-C6H4O); 7.21ꢂ
/
7.64 (m, 12H,
aryl). 13C-NMR: 25. 6 (CH2Sn); 26.8 (CH2CH2Sn);
H
Enraf Nonius CAD4 automatic diffractomer using Moꢂ
/
28.6 (CH2(CH2)2Sn); 28.8 (CH2(CH2)3Sn); 67.5
(CH2O); 114.7 (o-C6H4O); 26.6 (m-C6H4O); 126.7 (p-
C6H5); 128.1 (o-C6H5); 128.7 (m-C6H5); 129.1 (p-
C6H5Sn); 130.9 (m-C6H5Sn); 133.6 (i-C6H5); 134.5 (o-
C6H5Sn); 136.9 (i-C6H5Sn); 140.8 (i-C6H4); 158.6 (i-
˚
Ka radiation (lꢁ0.71069 A). Data were corrected for
/
Lp effects and, in the case of 10 and 12, absorption.
Refinement was based on F2; hydrogen atoms were
included at calculated positions.
The asymmetric unit of 12 was found to consist of one
molecule of the tin complex, and a disordered fragment
of solvent. The latter could not be fully modelled, but
best convergence was achieved by assigning the two
largest peaks in the electron density map to one full
chlorine atom and one half of a carbon atom respec-
tively. The disorder was compounded by the proximate
location of the solvent fragment to an inversion centre
implicit in the space group.
C6H4O). 119Sn-NMR:
ꢄ
/
157.2. 119mSn Mossbauer
¨
(mmsꢄ1): i.s.ꢁ
/
1.52; q.s.ꢁ
/
2.57; Gꢁ0.80. IR (KBr):
/
3063, 3026, 2944, 2867, 1605, 1518, 1487, 1471, 1429,
1290, 1267, 1244, 1190, 1176, 1142, 1055, 1038, 987, 839,
763, 723, 696, 688, 673, 439.
3.16. Synthesis of butyl[5-(4-biphenyloxy)pentyl]tin
dibromide (14)
Data
have
also
been
collected
on
This compound was prepared via a similar method as
ouflined above for 10 from bromine (2.08 g, 26.0 mmol)
in chloroform (250 ml) and 9 (3.70 g, 6.50 mmol).
Recrystallisation from hexane yielded 14 as a colourless
crystalline solid (1.60 g, 43%) m.p. 62 8C. Anal. Found
(Calc. for C21H28Br2OSn): C, 44.2 (43.9); H, 4.87
Ph3Sn(CH2)3OC6H4C6H5 (5).2 However, as a conse-
quence of poor sample quality, less than desirable
sample shape and a sharp fall-off in the crystal diffract-
ing power at u values beyond 158, relatively high esd
values and refinement factors were associated with this
structure determination. As a corollary of mediocre
(4.87)%. 1H-NMR: 0.87 (t, 3H, CH3); 1.10ꢂ
14H, 7 CH2); 3.93 (t, 2H, CH2O); 6.88 (d, 2H, o-
C6H4O); 7.16ꢂ
7.49 (m, 12H, Haryl). 13C-NMR: 13.5
(CH3); 25.4 (CH2Sn); 26.0 (CH3(CH2)2CH2Sn); 26.8
(CH2CH2Sn); 26.9 (CH3CH2CH2CH2Sn); 27.6
(CH3CH2); 28.6 (CH2(CH2)2Sn); 29.4 (CH2(CH2)3Sn);
/1.87 (m,
data, the intramolecular bond lengths in the C19ꢂ
/
C20ꢂ
/
/
2
C33H30OSn, Mꢁ
/
561.26, triclinic, aꢁ
99.23(2), bꢁ97.17(2), gꢁ
A , space group P1 (no. 2), Zꢁ4.
/
7.284(1), bꢁ
/18.423(4), cꢁ
/
˚
20.913(5) A, aꢁ
/
/
/
93.19(2)8, Uꢁ
/
2740.2(10)
3
˚
¯
/

P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ
/56
55
Table 1
Crystallographic data for 6, 8, 10 and 12
6
8
10
12
Empirical formula
Formula weight
Colour
C34H32OSn
1150.57
Colourless
C34H29NOSn
586.27
Colourless
C21H20Br2OSn
566.88
Colourless
C22.5H20Br2ClNOSn
634.36
Colourless
Crystal size (mm)
Crystal system
Space group
0.20ꢃ
Monoclinic
P21/c
/
0.20ꢃ
/0.30
0.25ꢃ
Triclinic
¯
P1 (no. 2)
/
0.25ꢃ
/
0.25
0.2ꢃ
Monoclinic
P21/n
/
0.2ꢃ
/0.15
0.2ꢃ
Triclinic
¯
P1 (no. 2)
/
0.2ꢃ0.25
/
Unit cell dimensions
˚
a (A)
˚
11.141(2)
10.778(2)
24.291(3)
7.413(1)
10.178(2)
19.924(3)
81.81(1)
89.46(1)
71.55(2)
1410.4(4)
2
9.854 (1)
7.630 (1)
27.932(3)
9.234(2)
10.259(2)
13.806(4)
108.79(2)
100.78(2)
94.30(2)
1203.4(5)
2
b (A)
˚
c (A)
a (8)
b (8)
g (8)
102.35(2)
94.97(1)
3
˚
V (A )
2849.3(8)
4
2092.2(4)
4
Z
m(Moꢂ
/
Ka) (mmꢄ1
)
0.920
4055
0.932
4821
5.047
3491
4.506
3771
Reflections collected
Independent reflections
Goodness-of-fit on F2
3947 [Rint
1.068
ꢁ/0.0621]
4433 [Rint
0.946
ꢁ/0.0117]
3280 [Rint
1.098
ꢁ/
0.0317]
3771 [Rint
1.083
ꢁ/0.0482]
R, Rw [I ꢀ
R, Rw (all data)
/
2s(I)]
0.0630, 0.1786
0.1508, 0.2889
0.0267, 0.0631
0.0429, 0.0738
0.0329, 0.0669
0.0873, 0.0862
0.0554, 0.1090
0.1378, 0.1511
C21ꢂ
/
O1 fragment of one of two molecules in the
References
asymmetric unit had to be restrained to ideal values in
the latter stages of refinement. While the geometry
about each tin in the asymmetric unit was, as expected,
tetrahedral, the distortions in the bond angles about
[1] T. Imori, T.D. Tilley, J. Chem. Soc. Chem. Commun. (1993) 1607.
[2] T. Imori, V. Lu, H. Cai, T.D. Tilley, J. Am. Chem. Soc. 117
(1995) 9931.
[3] N. Devylder, M. Hill, K.C. Molloy, G.J. Price, J. Chem. Soc.
Chem. Commun. (1996) 711.
Sn(2) (89.5ꢂ121.88) make meaningful structural com-
/
parisons with compounds (6) and (8) impossible. No
further comments are made on the structure of this
compound.
[4] V. Lu, T.D. Tilley, Macromolecules 29 (1996) 5763.
[5] K. Mochida, M. Hayakawa, T. Tsuchikawa, Y. Yokoyama, M.
Wakasa, H. Hayashi, Chem. Lett. (1998) 91.
[6] Y. Ding, J.Y. Corey, Abstracts of the ACS 36 (1995) 192.
[7] P. Braunstein, X. Morise, Chem. Rev. 100 (2000) 3541.
[8] N.R. Neale, T.D. Tilley, J. Am. Chem. Soc. 124 (2002) 3802.
[9] M. Okano, N. Matsumoto, M. Arakawa, T. Tsuruta, H.
Hamano, J. Chem. Soc. Chem. Commun. (1998) 1799.
[10] Y. Yokoyama, M. Hayakawa, T. Azemi, K. Mochida, J. Chem.
Soc. Chem. Commun. (1995) 2275.
Software used: SHELX-86 [34], SHELX-93 [35], DIFABS
[36], ORTEX [37].
4. Supplementary material
[11] R.D. Miller, J. Michl, Chem. Rev. 89 (1989) 1359.
[12] V.Y. Lu, T.D. Tilley, Macromolecules 33 (2000) 2403.
[13] E.K. Karikari, A.J. Greso, B.L. Farmer, R.D. Miller, J.F. Rabolt,
Macromolecules 26 (1993) 3937.
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
[14] F.C. Schilling, A.J. Lovinger, J.M. Zeigler, D.D. Davis, F.A.
Bovey, Macromolecules 22 (1989) 3055.
Data Centre, CCDC nos. 213854ꢂ213857 for com-
/
pounds 6, 8, 10 and 12, respectively. Copies of this
information may be obtained free of charge from The
Director, CCDC, 12 Union Road, Cambridge CB2 1EZ,
[15] R.D. Miller, D. Hofer, J. Rabolt, J. Am. Chem. Soc. 107 (1985)
2172.
[16] S.S. Bukalov, L.A. Leites, V. Lu, T.D. Tilley, Macromolecules 35
(2002) 1757.
UK (Fax: ꢀ44-1223-336033; e-mail: deposit@ccdc.ca-
/
[17] P.J. Collings, Liquid Crystals: Nature’s Delicate Phase of Matter,
2nd ed., Hilger, Bristol, 2002.
m.ac.uk or www: http://www.ccdc.cam.ac.uk).
[18] I.C. Khoo, Liquid Crystals: Physical Properties and Non-linear
Optical Phenomena, Wiley Interscience, New York, 1995.
[19] C.B. McArdle, Side-Chain Liquid Crystal Polymers, Blackie,
London, 1989.
Acknowledgements
[20] K.C. Molloy, P.C. Waterfield, J. Organomet. Chem. 424 (1992)
281.
We thank the EPSRC for financial support.

56
P.R. Deacon et al. / Journal of Organometallic Chemistry 687 (2003) 46ꢂ56
/
[21] J.L. Wardell, Formation and cleavage of the tinꢂ
/
carbon bond, in:
[28] R.H. Herber, J. Inorg. Nucl. Chem. 35 (1973) 67.
[29] N.W. Alcock, J.F. Sawyer, J. Chem. Soc. Dalton Trans. (1977)
1090.
P.G. Harrison (Ed.), Chemistry of Tin, Blackie, Glasgow, 1989, p.
145.
[22] A.G. Davies, in: E.W. Abel, F.G.A. Stone, G. Wilkinson (Eds.),
Comprehensive Organometallic Chemistry, vol. 2, Pergamon,
Oxford, 1995, p. 217.
[30] R.G. Jones, W. Ando, J. Chojnowski (Eds), Silicon-Based
Polymers: The Science and Technology of Their Synthesis and
Applications, Kluwer, Dordrecht, 2000.
[23] J. Holecek, M. Nadvornik, K. Handlir, A. Lycka, J. Organomet.
Chem. 241 (1983) 177.
[31] T.C.B. Mcleish, R.G. Jones, S.J. Holder, Macromolecules 35
(2002) 548.
[24] J. Susperregui, M. Bayle, J.M. Leger, G. Deleris, M. Biesemans,
R. Willem, M. Kemmer, M. Gielen, J. Organomet. Chem. 545
(1997) 559.
[32] K.C. Molloy, T.G. Purcell, K. Quill, I. Nowell, J. Organomet.
Chem. 267 (1984) 237.
[33] F.B. Kipping, J. Chem. Soc. (1928) 2370.
[34] G.M. Sheldrick, SHELX-86S, A Computer Program for Crystal
Structure Determination, University of Gottingen, Gottingen,
[25] M. Kemmer, M. Biesemans, M. Gielen, E.R.T. Tiekink, R.
Willem, J. Organomet. Chem. 634 (2001) 55.
[26] K. Jurkschat, J. Schilling, C. Mugge, A. Tzschach, J. Meunier-
Piret, M. van Meerscsche, M. Gielen, R. Willem, Organometallics
7 (1988) 38.
¨
¨
1986.
[35] G.M. Sheldrick, SHELX-93, A Computer Program for Crystal
Structure Refinement, University of Gottingen, Gottingen, 1993.
¨
¨
[27] E.V. van den Berghe, G.P. van der Kelen, J. Organomet. Chem.
26 (1971) 207.
[36] N. Walker, D. Stewart, Acta Crystallogr. Sect. A 39 (1983) 158.
[37] P. McArdle, J. Appl. Crystallogr. 28 (1995) 65.