Synthesis of symmetrical, substituted (alkane-,-diyl)(bis[3,3′-allyl dithioethers]) monomers for photoplastic polymer networks

Article abstract of DOI:10.1071/CH12278

Novel symmetrical (alkane-α,ω-diyl)(bis[3,3′-allyl dithioethers]) compounds and their ether analogues, have been synthesised from (alkane-α,ω-diyl)bis([2-{chloromethyl}allyl]sulfane) precursors, for use in crosslinked polymers which exhibit photoplastic behaviour. Facile synthesis and purification of these monomers was achieved if the alkane-α,ω-diyl moiety had at least one oxygen atom in this linker. The number of sulfur atoms in these monomers was varied from four to two to zero to produce monomers which can be used to evaluate their importance on the photoplasticity behaviour.

Full text of DOI:10.1071/CH12278

RESEARCH FRONT
CSIRO PUBLISHING
Aust. J. Chem. 2012, 65, 1165–1176
Full Paper
http://dx.doi.org/10.1071/CH12278
Synthesis of Symmetrical, Substituted (alkane-a,v-diyl)
(bis[3,39-allyl dithioethers]) Monomers for Photoplastic
Polymer Networks
A
A C
,
A
Cornelis M. Moorhoff, Wayne D. Cook,
Tara Schiller,
B
A B
,
Carl Braybrook, and San H. Thang
A
Department of Materials Engineering, Monash University, Clayton,
Vic. 3800, Australia.
B
Materials Science and Engineering, CSIRO, Clayton, Vic. 3168, Australia.
C
Corresponding author. Email: wayne.cook@monash.edu
Novel symmetrical (alkane-a,v-diyl)(bis[3,30-allyl dithioethers]) compounds and their ether analogues, have been
synthesised from (alkane-a,v-diyl)bis([2-{chloromethyl}allyl]sulfane) precursors, for use in crosslinked polymers which
exhibit photoplastic behaviour. Facile synthesis and purification of these monomers was achieved if the alkane-a,v-diyl
moiety had at least one oxygen atom in this linker. The number of sulfur atoms in these monomers was varied from four to
two to zero to produce monomers which can be used to evaluate their importance on the photoplasticity behaviour.
Manuscript received: 12 June 2012.
Manuscript accepted: 20 July 2012.
Published online: 8 August 2012.
Introduction
such as 3-mercapto-2-mercaptomethyl-1-propene (3,
Scheme 1).[1] To illustrate this, when a mixture of 3-mercapto-
2-mercaptomethyl-1-propene (3, 1 equiv.) and epichlorohydrin
(4, 2 equiv.) was added to a suspension of NaH (2 equiv.)
in tetrahydrofuran (METHOD 2), the bisepoxide, 2,20-
(2-methylenepropane-1,3-diyl)bis(sulfanediyl)bis(methylene)
dioxirane (5) was obtained in a modest yield of 50 % after
purification, whereas using potassium carbonate as a base, in
either refluxing acetone or butanone, none of compound 5 could
be isolated (Scheme 2).[1]
Although the method using NaH as a non-nucleophilic base
worked very well for the preparation of 5, this method did not
work for vinyloxyethyl thioethers due to a very sluggish reaction
leading to an incomplete alkylation and secondary reaction
products. In this case we used 2-chloroethyl vinyl ether (6) with
sodium methoxide as a base (Scheme 1) in a modification of the
method employed by Evans and Rizzardo[6,7] and Scott and
In a recent communication[1] we described the synthesis of
novel symmetrical 3,30-allyl dithioethers 1 (R ¼ R0) (Scheme 1).
These compounds can function either as homopolymerizable
monomers or can be copolymerized with other monomers
(such as tri- or tetramercaptans) to form three-dimensional
polymer networks with photoplastic behaviour.[2–4] Photo-
plasticity is the phenomenon whereby a solid crosslinked
polymer can deform permanently on application of a load only
when the polymer is irradiated. These polymers have important
applications, e.g. for the re-adaptation of a dental filling material
to the dental cavity to compensate for curing shrinkage.[5]
We have previously noted[1] the importance of the choice of
base for the preparation of compounds 1. We developed
methods whereby NaH can be used to furnish 1, by either
starting from a dichloride (METHOD 1) such as 3-chloro-2-
chloromethyl-1-propene (2) or from a dimercaptan (METHOD 2)
METHOD 2
METHOD 1
2ꢂ NaH
2ꢂ HS
Cl
R
X
R
2ꢂ
HS
3ꢀ
3
Rꢀ
2
R
2ꢂ NaH
S
S
ꢁ
SH
Cl
ꢁ
THF, 0ꢃC
1
THF, r.t.
2
1
3
Syringe one
METHOD 3
MeOH, 55ꢃC
Synchronised
addition
2ꢂ NaOMe
Syringe two
Scheme 1. Preparation of symmetrical 3,30allyl dithioethers 1.
Journal compilation Ó CSIRO 2012
www.publish.csiro.au/journals/ajc

1166
C. M. Moorhoff et al.
co-workers.[8,9] Thus, when a mixture of dimercaptan 3
(1 equiv.) and 6 (2 equiv.) in methanol and sodium methoxide
(2 equiv.) in methanol was added together synchronously
(METHOD 3, Scheme 1), 8-methylidene-3,13-dioxa-6,10-
dithiapentadeca-1,14-diene (previously named 2-methylene-
propane-1,3-di[thioethyl vinyl ether] and abbreviated as
MDTVE, 7) (Scheme 2) was obtained in 78 % yield.
causing, once more, a b-scission and the formation of a new
sulfanyl radical. Thus, network strands are broken and then
reformed in new arrangements, continuously, and any stress that
had been imposed on the strands can be relieved. In the end, the
course of radical combination and loss of the photoinitiator
depletes the concentration of radicals and that leads to the
termination of the chain rearrangements thus restricting the
extent of stress relaxation or shape change.
Our studies of the photoplastic behaviour of polymer net-
works of MDTVE 7 cured with PETMP 8,[2,3] has led us to
investigate polymer networks based on monomers having two
3,30-allyl dithioether functionalities and even three 3,30-allyl
dithioether functionalities in the molecule. In this paper we
disclose how we have applied the synthetic methods we have
learned in our previous work,[1] and extended these syntheses for
the preparation of novel (alkane-a,v-diyl)bis([2-{2-(vinyloxy)
ethylthiamethyl}allyl]sulfane) (abbreviated to: [alkane-a,v-
diyl]bis[3,30-allyl dithioethers]) and analogous monomers 14
(Scheme 4) for the preparation of photoplastic polymer
The distinctive photoplastic behaviour of a cured, thiol-ene
network,[2,3] in this case represented as the reaction product
of MDTVE
7 (2 equiv.) and pentaerythritol tetrakis(3-
mercaptopropionate)(PETMP)8(1 equiv.)–showninScheme3
as polymer network 9 schematically represented as 10 – is due to
the (2-methylenepropane-1,3-diyl)bis(sulfandiyl) moiety 12 of
the polymer strands 11. These sub-units 12 have methylene
groups which can be attacked by photogenerated carbon radi-
cals, Rꢀ, at the least hindered carbon, C1 of the alkene, to form a
bond with simultaneous b-cleavage to regenerate another alkene
and a sulfanyl radical (Scheme 3). This sulfanyl radical is then
able to attack another alkene in a neighbouring polymer strand,
O
METHOD 2
S
HS
SH
S
S
2ꢂ Cl
ꢁ
O
O
O
O
4
3
5
METHOD 3
S
Cl
2ꢂ
O
ꢁ
3
6
7 MDTVE
O
O
O
HS
SH
SH
O
O
O
O
HS
O
8 PETMP
Scheme 2. Monomer compounds for photoplastic polymer networks.
S
O
S
S
O
O
O
O
S
S
S
S
O
O
O
O
O
O
S
S
O
S
3D network: 10
9
n
S
S
ꢄ
ꢄ
11
3ꢀ
3
Rꢅ
Rꢅ
Rꢀ
Rꢀ
Rꢀ
Rꢅ
•S
2
S
S
S
S
S
•
1
R
R
•R
12
Scheme 3. Identification of a 3D photoplastic polymer network.

(Alkane-a,v-diyl)(bis[3,30-allyl dithioethers]) Monomer
1167
networks. Early in our investigations, we suspected that a three-
dimensional network 10 having the essential 3,30-allyl
dithioether unit 12 too close to the cross-linkage, may actually
diminish the rate and final extent of photoplasticity (Scheme 3).
This could occur because, during the sulfanyl-radical attack and
subsequent b-cleavage, the resulting new sulfanyl-radical arm
may be too short and unable to attack another allylic dithio ether
group in the nearest neighbouring polymer strand. To enable
investigation of this hypothesis, we have designed monomers
for the synthesis of photoplastic polymer networks where we
modify the strands in 11 by increasing their length and by
replacing the single 3,30-allyl dithioether units 12 in the polymer
strands with two or three 3,30-allyl dithioether ether units, such
as in polymer strand 13 (Scheme 4). To synthesise monomers
with two 3,30-allyl dithioether units, we specifically designed it
with symmetry to have synthetic control.
Results and Discussion
The most direct route to synthesise monomers of the type 14 was
to use either METHOD 1 or METHOD 2 as depicted in
Scheme 5. Condensation of excess allylic dimercaptan 3 with
dihalide 15 (METHOD 2) in the presence of two molar
equivalents of NaH should form the bis(allylic)dimercaptan 16
(Y ¼ S), which would then be transformed, with one further
reaction, into two final products 14 (Y ¼ S, Z ¼ O or S)
(Scheme 5).[1] However, the lengthier route, METHOD 1,
reacting the allylic dichloride 2 with dimercaptan 17 was more
attractive because with this superior approach we should be able
to synthesise all four desired products 14 from 18 (Y ¼ O or
S).[1] For example, with in situ generated sodium ethyl xan-
thogenate, compound 18 (Y ¼ O or S) should be transformed,
into the bis(allylxanthates) 19 and then further reacted with
ethylene diamine to release the bis(allylmercaptan) 16 (Y ¼ O
or S). Then the reaction of 2-chloroethyl vinyl ether (6) with 16,
using sodium methoxide as base (METHOD 3, Scheme 5),
should furnish the desired photoplastic monomers 14 (Z ¼ S,
Y ¼ O or S) (Scheme 5). Alternatively, the dichloride 18 (Y ¼ O
or S) should also react with 2-vinyloxyethanol (20) in the
presence of a suitable base to obtain the monomers 14 (Z ¼ O,
Y ¼ O or S) (Scheme 5) yielding a monomer with no allylic
Z
Y
Y
Z
12
13, Y ꢄ O or S and Z ꢄ O or S
O
O
Z
Y
Y
Z
14, Y ꢄ O or S and Z ꢄ O or S
Scheme 4. (Alkane-a,v-diyl)bis([2-{2-(vinyloxy)ethylthiamethyl}allyl]
sulfane) monomers.
O
O
Z
Y
Y
Z
14, Z ꢄ O, Y ꢄ O or S
2ꢂ Base
O
HO
20
METHOD 1
2ꢂ Base
2ꢂ
Cl
Cl
HY
YH
ꢁ
Cl
Y
Y
Cl
17, Y ꢄ O or S
2
18, Y ꢄ O or S
2ꢂ
NaSC[ꢄS]OEt
S
S
EtO
S
Y
Y
S
OEt
19, Y ꢄ O or S
NH2
H2N
METHOD 2
2ꢂ HS
2ꢂ Base
ꢁ
SH
X
X
HS
Y
Y
SH
3
15, X ꢄ Cl
16, Y ꢄ O or S
2ꢂ Base
METHOD 3
O
Cl
Y
6
O
O
Z
Y
Z
14, Z ꢄ S, Y ꢄ O or S
Scheme 5. Synthetic outline for (alkane-a,v-diyl)bis([2-{2-(vinyloxy)ethylthiamethyl}allyl]sulfane) monomers 14.

1168
C. M. Moorhoff et al.
thioether units to act as a control in photoplasticity experiments.
The unit 12 of 13 whereby the heteroatoms Z or Y could be
oxygen, either near the cross-linkage (Z ¼ O, Y ¼ S) or distant to
that (Y ¼ O, Z ¼ S), allow differentiation between longer and
shorter sulfanyl radicals of photoplastic polymer systems 13
(Scheme 4).
is not very polar and resembles the polarity of a methylene unit.
A comparison of the Pauling electronegativities show that sulfur
(2.58) is much closer to carbon (2.55) or hydrogen (2.20) but not
oxygen (3.44).[10,11] for synthetic ease it is essential to have at
least one oxygen in the linker between the allylic groups so that
the desired product can be separated from its oligomers. In
addition, the short aliphatic linker in 21 and 22 (Scheme 6)
would limit the photoplasticity of the final polymer because the
radical strands would be too short to reach neighbouring allylic
dithioether groups (see Scheme 3). For example, the cured
polymer network 9, shows limited photoplasticity because the
network strands are too short.[3] Therefore, we focussed on
longer aliphatic linkers containing oxygen.
For example, allylic dichlorides 18 containing ether-based
linkers such as diethylene glycol and triethylene glycol were
found to be much easier to purify because each compound
showed significant differences in their TLC Rf-values. Thus,
the reaction of a 1 : 2 mixture of diethylene glycol, 3-chloro-2-
chloromethyl-1-propene (2), and excess NaH in tetrahydrofuran
at room temperature for 15 h produced the expected dichloride
23 (Scheme 7) which was purified by chromatography from
other impurities but the yield was only 8 % and the major
product was the triallyl dichloride 24 also in a low yield of
13 %. A little of the crown ether 25 was isolated. In contrast,
when the reaction was performed with triethylene glycol, under
In monomer 14 (Scheme 4), the selection of the linker group
between the two allylic groups is expected to be very important
to the photoplasticity of the final polymer because it affects the
length of polymer strand terminated by the sulfanyl radical. In
addition, this linker group cannot contain aromatic species
because this would lead to inflexible polymer strands. We
initiated this study using METHOD 1 (Scheme 5) by reacting
either 2-methylpropane-1,3-dimercaptan or propane-1,3-
dimercaptan with an excess of 2-chloro-2-chloromethyl-1-propene
(2) in the presence of NaH (2 equiv.) to furnish dichlorides 21
and 22, respectively, as oils (Scheme 6). However, analysis of
the 1H-NMR spectrum of each of the resulting reaction showed
that the compounds had impurities of higher oligomers. Purifi-
cation by distillation or crystallisation was not applicable. These
mixtures could not easily be purified by silica gel chromatogra-
phy as thin-layer chromatography (TLC) analysis revealed.
Mixtures of similar sulfur oligomers with no oxygen in their
structures are extremely difficult to separate because they have
very similar Rf values. The reason for this is that the sulfane unit
2ꢂ NaH
2ꢂ
ꢁ
HS
SH
Cl
Cl
Cl
S
S
Cl
THF
2
2
21, 56 %
2ꢂ NaH
2ꢂ
HS
SH
Cl
Cl
Cl
S
S
Cl
ꢁ
THF
22, 38 %
Scheme 6. Preparation of (alkane-a,v-diyl)bis([2-{chloromethyl}allyl]sulfane with only sulfur in the backbone.
2ꢂ NaH
O
O
6ꢂ 2
ꢁ
HO
OH
Cl
O
O
Cl
THF
O
23, 8 %
O
O
O
O
O
ꢁ
ꢁ
O
O
O
Cl
Cl
24, 13 %
25, 7 %
2ꢂ NaH
O
OH
ꢁ
6ꢂ 2
HO
O
THF
O
O
O
Cl
O
Cl
O
O
26, 62 %
O
O
O
O
Cl
O
O
Cl
ꢁ
27, 12 %
Scheme 7. Preparation of (alkane-a,v-diyl)bis([2-{chloromethyl}allyl]ethers based on diethylene glycol and triethylene
glycol.

(Alkane-a,v-diyl)(bis[3,30-allyl dithioethers]) Monomer
1169
exactly the same conditions, the outcome was dramatically
different and a yield of 62 % was obtained of the required
dichloride 26 along with 12 % of the triallyl dichloride 27, but
no cyclised product analogous to 25 was found (Scheme 7). All
products 23 to 27 were simple to separate by chromatography on
silica gel. For example, the dihalides 26 and 27 (Scheme 7), have
Rf values of 0.39 and 0.13 (using 1 : 1 EtOAc : hexane). We
cannot explain the considerable difference in yields between the
alkylation reactions of diethylene glycol and triethylene glycol
with excess 2, but it determined our choice of derivatives to be
based on triethylene glycol. The synthetic target molecules for
compound 14 are outlined in Scheme 8.
(1 equiv.), with NaOMe as base caused extensive methoxylation
of 26. Performing the reaction in anhydrous THF with slight
excess NaH (.2 equiv.), gave the desired monomer 14a
(Scheme 9) as a colourless oil however, the optimum conditions
for this reaction were rather narrow. For example, it was found
that when the addition of 26 and 20 to NaH was carried out over a
period of 5 min, this addition-rate was too slow and the alkyl-
ation reaction did not proceed to completion. However, fast
addition (approx. 1 s) of a mixture 20 and 26 to NaH did yield the
desired product 14a. Unfortunately, this very rapid addition
gave a strong exotherm that could not be controlled with larger
scale reactions (.2 g). Alternatively, when 2-vinyloxyethanol
(20) and bis(allyl) dichloride 26 were stirred in butanone for 15 h
at 708C under phase-transfer conditions using potassium car-
bonate as a base and benzyltriethylammonium chloride
(BTEAC) as the catalyst, the product 14a was obtained in a
43 % yield and this procedure could be repeated on a large scale
(Scheme 9).
In the synthesis of bis(allyl) di(vinyloxyethyl) monomer 14a,
the alkylation of bis(allyl) dichloride 26 and 2-vinyloxyethanol
(20) was quite troublesome. Attempted alkylation of
2-vinyloxyethanol (20, 2 equiv.) and bis(allyl) dichloride 26
Using similar phase-transfer conditions, the product 14b, a
colourless oil, was obtained in a 52 % yield (Scheme 10) from
2-vinyloxyethanol (20) and bis(allyl) dichloride 28[1]; the
contaminating semi-alkylated product 29 was removed with
difficulty by chromatography.
O
O
O
O
O
S
O
O
O
O
O
S
O
O
O
O
14a
To synthesise 14c, the dichloride 26 was treated with soluble
sodium ethyl xanthogenate in ethanol to give the bis(xanthate)
30 (Scheme 11). Compound 30 then reacted with ethylene
diamine to give the dimercaptan 31 as a colourless oil. After
purification it was found to have little, if any, sulfurous smell,
apparently due to the increase in chain length and decrease of its
volatility, as explained in detail in the literature.[12] The dimer-
captan 31 and chloride 6 was added synchronously with a
solution of sodium methoxide to give 14c as a colourless liquid
in an unoptimised yield of 43 %.
14b
O
O
O
O
O
S
S
S
S
S
O
S
O
O
O
14c
O
14d
Scheme 8. Synthetic target molecules for 3D photoplastic monomer
The monomer 14d was synthesised in a similar fashion
(Scheme 12). The dichloride 28[1] was treated with sodium ethyl
compounds.
O
HO
2ꢂ
O
O
Cl
Butanone 70ꢃC
20
Cl
O
O
26
K2CO3, BTEAC, 24 h
O
O
O
O
O
O
O
O
14a, 43 %
Scheme 9. Synthesis of compound 14a.
O
HO
2ꢂ
Butanone 70ꢃC
O
S
Cl
20
Cl
S
O
K2CO3, BTEAC, 24h
28
O
O
S
O
O
S
O
O
14b, 52 %
O
O
S
Cl
O
S
O
29
Scheme 10. Synthesis of compound 14b.

1170
C. M. Moorhoff et al.
2
ꢂ
NaSC[ꢄS]OEt
O
O
O
O
Cl
S
Cl
O
O
O
O
EtOH
26
NH2
S
H2N
O
O
S
S
30, 98 %
O
Cl
2ꢂ
6
O
O
O
O
SH
S
HS
S
O
O
O
2
ꢂ
NaOMe
31, 53 %
O
O
O
14c, 43 %
Scheme 11. Synthesis of compound 14c.
2ꢂ
NaSC[
ꢄS]OEt
O
O
S
S
Cl
S
O
O
Cl
S
S
EtOH
28
NH2
S
H2N
O
O
S
S
32, 97 %
O
Cl
ꢂ
2
6
O
O
S
S
SH
S
O
HS
S
S
2
ꢂ NaOMe
33, 72 %
O
O
S
O
14d, 35 %
Scheme 12. Synthesis of compound 14d.
xanthogenate in ethanol to give a pale yellow oil of the
bis(xanthate) 32 (Scheme 12). Release of the dimercaptan 33
was accomplished with ethylene diamine and then purified by
chromatography. Compound 33 also had little, if any, smell[12]
and at room temperature was a colourless solid. The last step in
this reaction sequence was carried out by treating the mixture of
compound 33 and chloride 6 (2 equiv.) with sodium methoxide
in methanol. The product 14d was purified by chromatography
to give a colourless oil in an unoptimised yield of 35 %. This oil
crystallized slowly at room temperature.
The practical importance of having oxygen in the linker
in-between the allyl groups of precursors 18 and final products
14 (Scheme 5) cannot be overstated. Monomers containing more
sulfur atoms are less able to be chromatographically separated
from their derivatives and impurities than monomers with fewer
sulfur atoms. The differences of Rf values between the mono-
mers 14 are quite dramatic. The polar, oxygenated monomer 14a
had an TLC Rf value of 0.14 (1 : 1 EtOAc : hexanes) whereas the
mixed sulfur-oxygen analogues 14b and 14c had Rf values of
0.49 and 0.52 (1 : 1 EtOAc : hexanes), respectively, and the
relatively non-polar tetrathia analogue 14d with an Rf value at
0.63 (1 : 1 EtOAc : hexanes) compared with MDTVE 7 with an
Rf value at 0.68 (1 : 1 EtOAc : hexanes).
The series of photoplasticity monomers was extended by
synthesising compound 37, having three 3,30-allyl dithioether
ether units, in a similar fashion as for the preparation of 14d
(Scheme 13). The tris(allyl) dichloride 341 was treated with
excess sodium ethyl xanthogenate in ethanol, and gave after
workup a faint yellow oil of the bis(xanthate) 35. The dimer-
captan 36 was released from 35 with ethylene diamine at room
temperature, and after chromatography over silica gel yielded an
odourless, white solid of 36. Synchronous combination of a
mixture of dithiol 36 and 6 in a ratio of 1 : 2 with a solution of
sodium methoxide (2 equiv.) in methanol at 508C, gave com-
pound 37 as a white solid in an unoptimised yield of 39 %.
The FT-IR spectra of the four diallylic monomers are shown
in Fig. 1 and the peak assignments[13] are given below. The
allylic peak at 1615 cmꢁ1 is clearly obvious in all monomers but
it overlapped with the vinyl ether peak at 1635 cmꢁ1. The vinyl
ether (CH2¼CH-O-CH2-) stretch at 1200 cmꢁ1 is visible in

(Alkane-a,v-diyl)(bis[3,30-allyl dithioethers]) Monomer
1171
O
S
S
O
Cl
S
O
O
S
Cl
34
EtOH
S
2ꢂ NaSC[ꢄS]OEt
S
S
O
O
S
O
O
EtO
S
S
S
O
O
O
S
S
S
OEt
35, 77 %
NH2
H2N
S
S
36, 40 %
2ꢂ
HS
O
SH
O
Cl
6
2ꢂ NaOMe/THF
O
O
S
S
O
O
S
S
O
O
S
S
37, 39 %
Scheme 13. Preparation of tris(allyl dithio) divinylethoxy monomer 37.
Conclusions
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
According to a simple synthetic protocol, the preparation of a
series of symmetrical (alkane-a,v-diyl)bis([2-{2-(vinyloxy)
ethylthiamethyl}allyl]sulfane) compounds and their analogous
ethers 14 have been accomplished from (alkane-a,v-diyl)bis
([2-{chloromethyl}allyl]sulfane) 18 and like compounds.
Monomers 14 were designed for the preparation and the study of
photoplastic three dimensional polymer networks. In purifying
these compounds, it became apparent that the linker between the
two allylic groups of the various (alkane-a,v-diyl)bis
([2-{chloromethyl}allyl]sulfane) 18 compounds should have at
least one oxygen in the back-bone to facilitate purification of
these and all other derived compounds. Having derivatives of
triethylene glycol as a linker proved both successful in yield and
purity in this endeavour.
7
7
14a
14b
14c
14d
14a
14b
14c
14d
Experimental
General
All chemicals were used as received unless otherwise specified.
3-Chloro-2-chloromethyl-1-propene (2), was purchased from
Secant Chemicals Inc. (MI, USA). 1,3-Propanedithiol, diethy-
lene glycol, triethylene glycol and 60 % NaH in oil were pur-
chased from Sigma Aldrich (Castle Hill, NSW, Australia). 60 %
NaH in oil suspension was washed twice with a mixture of
hexane isomers (termed ‘hexanes’ and supplied by Merck). All
reactions were performed under nitrogen unless stated other-
wise. Tetrahydrofuran was dried over NaH. The preparation of
3-mercapto-2-mercaptomethyl-1-propene (3), and compounds
28 and 34, was carried out as described before.[1] 2-Methyl-1,3-
propanedithiol was made according to Scott et al.[9] Some mass
spectra experiments were carried out on a Waters Q-TOF II
instrument, employing electrospray ionisation (ESI) with a
35 eV cone voltage and employing a Lockspray source and
sodium iodide as a reference sample. Other mass spectra
experiments were carried out on a ThermoQuest MAT95XP
4000
3000
2000 1800 1600 1400 1200 1000 800 600
Wavelength [cmꢆ1
]
Fig. 1. FT-IR ATR spectra of monomer compounds 7, 14a, 14b, 14c,
and 14d.
these monomers and also in 7. The aliphatic -CH2-O-CH2-
asymmetric stretch is seen as a large peak near 1100 cmꢁ1 in
monomers 14 but not in 7. The intensity of the aliphatic -CH2-O-
CH2- asymmetric stretch in compounds 14 decrease in size as
the allylic ether is substituted by the allylic thio-ether in these
compounds. The aliphatic -CH2-S-CH2- sulfide is usually small
and does not have a characteristic wavenumber and so is not
identified in the spectra.
The mechanical properties, including photoplasticity, of the
polymers derived from these new monomers and co-monomers,
will be reported elsewhere.

1172
C. M. Moorhoff et al.
instrument, employing electron impact (EI) at 70 eV and per-
fluorokerosene as a reference sample. NMR spectra were run on
a Bruker Avance III 400 (9.4 Tesla magnet) with a 5 mm
broadband inverse probe, 1H at 400.13 MHz, or a Bruker
DPX300 (7.05 Tesla magnet) with a 5 mm quad 1H/13C
(d, 4H, J 0.9, SCH2C¼), 4.18 (d, 4H, J 0.6, ClCH2), 5.07 (d, 2H, J
0.9, HC¼C), 5.21 (d, 2H, J 0.6, HC¼C). dC (75 MHz, CDCl3)
28.4 (CH2), 30.0 (2ꢂ SCH2-allyl), 34.7 (2ꢂ CH2S), 45.8 (2ꢂ
ClCH2-allyl), 117.1 (2ꢂ H2C¼), 141.1 (2ꢂ ¼C).
1
switchable probe, H at 300.13 MHz, or a Bruker AV200 (4.7
2,12-Bis(chloromethyl)-4,7,10-trioxatrideca-1,12-diene
(23) and 2,22-Bis(chloromethyl)-12-methylene-
4,7,10,14,17,20-hexaoxatricosa-1,22-diene (24)
Tesla magnet) with 5 mm 1H/13C probe with Z-gradients at 308C
in CDCl3 using the residual chloroform peaks at 7.25 ppm as a
reference in proton and 77.0 ppm in carbon spectra. Abbrevia-
tions for multiplets are ‘sm’ for a sharp multiplet and ‘dm’ for a
doublet of multiplets and is caused by small coupling constants
of the multiplets (,1 Hz). These multiplets cannot be accurately
analysed but are clearly visible. A Nicolet 6700 FTIR was used
to collect the ATR spectra. Silica gel on plastic TLC plates were
obtained from Merck. Only some of the compounds on TLC
could be observed clearly by UV (254 nm) fluorescence, how-
ever neutral aqueous potassium permanganate solution devel-
oped most of the sulfur- and alkene-based products on TLC very
clearly - the excess potassium permanganate was then removed
with gentle running water.
A mixture of 3-chloro-2-chloromethyl-1-propene (2) (15 g,
120.0 mmol, 6 equiv.) and diethylene glycol (2.12 g, 20 mmol,
1 equiv.) in anhydrous THF (1 mL) was added within 5 min to a
suspension of NaH (1.20 g, 50.0 mmol, 2.5 equiv.) in anhydrous
tetrahydrofuran (30 mL) at room temperature. A vigorous exo-
thermic reaction occurred with the simultaneous evolution of
hydrogen gas. The mixture turned brown and was stirred for 15 h
at room temperature. The suspension was diluted with 1 : 1
THF : hexanes (60 mL) and filtered over a bed of silica gel (3 cm
diameter, 3 cm thick). The filter was further eluted with 1 : 1
THF : hexanes (100 mL) and the combined filtrate rotary evap-
orated dry on a hot waterbath (808C) to give a crude oil. This
product was then chromatographed on a 20 cm column with
silica gel (50 g) and eluted with 95 : 5 hexanes : EtOAc to give
cyclo-compound 25 (0.23g, 7 %). Rf (1 : 1 EtOAc : hexanes) ¼
0.68. dH (300 MHz, CDCl3) 3.6–3.7 (m, 8H, OCH2), 4.08 (t, 4H,
J 0.3, CH2-allyl), 5.16 (t, 2H, J 0.3, H2C¼). dC (75 MHz, CDCl3)
69.9 (2 ꢂ O-CH2), 70.9 (2 ꢂ O-CH2), 72.0 (2 ꢂ O-CH2), 114.0
(H2C¼), 143.5 (¼C) ppm. The eluant was increased to 4 : 1
hexanes : EtOAc to give compound 23 (0.43 g, 8 %). Rf (1 : 1
EtOAc : hexanes) ¼ 0.54. dH (300 MHz, CDCl3) 3.58–3.62 (m,
4H, OCH2), 3.63–3.64 (m, 4H, OCH2), 4.10 (d, 4H, J 0.9, CH2-
allyl), 4.11 (s, 4H, CH2-allyl), 5.23 (dt, 2H, J 1.2, 0.9, HC¼),
5.28 (dm, 2H, J 0.9, HC¼). dC (75 MHz, CDCl3) 45.1 (2 ꢂ
ClCH2), 69.7 (2 ꢂ OCH2), 70.6 (2 ꢂ OCH2), 71.3 (2 ꢂ OCH2),
116.7 (2 ꢂ H2C¼), 142.0 (2 ꢂ ¼C). m/z (EI) 247 ([M ꢁ Cl]þ,
5 %), 177 (38 %), 133 (22 %), 91 (35 %), 89 (100 %), 73 (45 %),
55 (31 %). m/z (HRMS) Anal. Calc. for C12H20O335Cl [M ꢁ Cl]þ:
247.1095. Found: 247.1093. The eluant was then further
increased to 3 : 2 hexanes: EtOAc to give colourless compound
24 (0.58 g, 13 %). Rf (1 : 1 EtOAc: hexanes) ¼ 0.27. dH
(300MHz, CDCl3) 3.56–3.62 (m, 8H, OCH2), 3.63–3.68 (m,
8H, OCH2), 4.01 (dd, 4H, J 0.9, 0.9, CH2-allyl), 4.09 (d, 4H,
J 0.9, CH2-allyl), 4.10(s, 4H, CH2-allyl), 5.17 (t, 2H, J 0.9, HC¼),
5.22 (dt, 2H, J 1.2, 0.9, HC¼), 5.28 (dm, 2H, J 1.2, HC¼). dC
(75 MHz, CDCl3 45.0 (2 ꢂ ClCH2), 69.5 (2 ꢂ OCH2), 69.6
(2ꢂ OCH2), 70.5 (2ꢂ OCH2), 70.6 (2 ꢂ OCH2), 71.2 (2ꢂ
OCH2), 71.7 (2 ꢂ OCH2), 114.07 (H2C¼), 116.89 (2 ꢂ H2C¼),
142.12 (2ꢂ ¼C), 142.62 (¼C). m/z (EI) 405 ([Mꢁ Cl]þ, ,1 %);
263 (,1 %); 247 (1%), 187 (7%), 177 (10 %), 159 (14 %), 135
(11 %), 133 (16 %), 97 (10 %), 91 (31 %), 89 (88%), 73 (100 %),
55 (51 %). m/z (HRMS) Anal. Calc. for C20H34O635Cl [M ꢁ Cl]þ:
405.2038. Found: 405.2043.
(2-Methylpropane-1,3-diyl)bis([2-{chloromethyl}allyl]
sulfane) (21)
A neat mixture of 3-chloro-2-chloromethyl-1-propene (2) (12 g,
96.0 mmol, 5.9 equiv.) and 2-methyl-1,3-propanedithiol (2.00 g,
16.4 mmol, 1 equiv.) was added within 5 min to NaH (0.84 g,
35.0 mmol, 2 equiv.) in anhydrous THF (30 mL) at room tem-
perature. A slow evolution of hydrogen gas occurred and the
mixture was further stirred at room temperature for 4 days. The
grey suspension had turned yellow-white. This mixture was
diluted with THF (30 mL) and filtered over a bed of silica gel
(3 cm diameter and 3 cm thick). The filter was further eluted
with THF (40 mL) and the filtrate rotary evaporated dry on a hot
waterbath (708C) to give 2.98 g crude product as a pale-yellow
oil. Chromatography on 60 g silica gel and elution with 5 : 95
EtOAc : hexanes gave product 21 (2.75 g, 56 %) with minor
inseparable higher oligomers as impurities. dH (200 MHz,
CDCl3) 1.06 (d, 3H, J 6.8, CHCH3), 1.87 (octet, 1H, J 6.8,
CHCH3), 2.34 (dd, 2H, J 12.8, 6.8, CHCH2S), 2.52 (dd, 2H,
J 12.8, 6.0, CHCH2S), 3.27 (d, 4H, J 1.0, SCH2), 4.19 (d, J 1.0,
4H, ClCH2), 5.09 (dt, 2H, J 1.0, 1.0, HC¼C), 5.23 (d, 2H, J 1.0,
HC¼C). dC (75 MHz, CDCl3) 19.4 (Me), 33.2 (CH), 35.4
(2 ꢂ SCH2-allyl), 37.6 (2 ꢂ CH2S), 45.8 (2 ꢂ ClCH2), 117.2
(2 ꢂ H2C¼), 141.2 (2 ꢂ ¼C) ppm.
1,3-Bis(2-(chloromethyl)allylthio)propane (22)
A mixture of 3-chloro-2-chloromethyl-1-propene (2) (13.39 g,
107mmol, 5.4 equiv.) and 1,3-propanedithiol (2.16 g, 20 mmol,
1 equiv.) in anhydrous THF (1mL) was added within 5 min to a
stirred suspension of NaH (1.20 g, 50.0 mmol, 2.5 equiv.) in
anhydrous THF (30 mL) at room temperature. A slow evolution
of hydrogen gas occurred during the addition. After the addition,
the mixture was stirred at room temperature for 24 h. The grey
suspension-mixture had changed to a yellow-white colour. This
mixture was diluted with a 1 : 1 mixture THF : hexanes (60 mL)
andfilteredoverabedofsilicagel(3cmdiameterand3 cmthick).
The filter was further eluted with 1 : 1 THF : hexanes (100mL)
and the filtrate rotary evaporated dry over a waterbath (808C) to
give the crude product as a slightly pale-yellow oil. Chromatog-
raphy on a 50 g silica gel column, and elution with 5 : 95
EtOAc : hexanes gave 2.66 g of an inseparable mixture of 82%
pure compound 22 (38 %) and other oligomers. dH (300MHz,
CDCl3) 1.80 (p, 2H, J 6.9, CH2), 2.48 (t, 4H, J 6.9, SCH2), 3.26
2,15-Bis(chloromethyl)-4,7,10,13-tetraoxahexadeca-1,15-
diene (26) and 2,28-Bis(chloromethyl)-15-methylene-
4,7,10,13,17,20,23,26-octaoxanonacosa-1,28-diene (27)
A mixture of 3-chloro-2-chloromethyl-1-propene (2) (15 g,
120 mmol, 6 equiv.) and triethylene glycol (3.0 g, 20 mmol,
1 equiv.) was added all at once to a stirred suspension of NaH
(1.02 g, 43 mmol, 2.1 equiv.) in anhydrous tetrahydrofuran
(30 mL) at room temperature (vigorous evolution of H2, and
temperature increased immediately to 508C). This mixture was
stirred for 5 h at room temperature. The resulting yellowish-

(Alkane-a,v-diyl)(bis[3,30-allyl dithioethers]) Monomer
1173
white suspension was diluted with THF (30 mL) and filtered
over a bed of silica gel (3 cm diameter and 3 cm thick). The filter
was further eluted with THF (30 mL). This clear filtrate was
rotary evaporated dry on a hot waterbath (808C) to give a crude,
pale-yellow oil. Chromatography of this oil on a 30 cm column,
packed with silica gel (90 g), and elution with 3 : 2 hexanes :
EtOAc gave colourless compound 26 (4.04 g, 62 %). Rf (1 : 1
EtOAc : hexanes) ¼ 0.36. dH (300 MHz, CDCl3) 3.58–3.61 (m,
4H, OCH2), 3.64–3.68 (m, 4H, OCH2), 3.65 (s, 4H, OCH2), 4.10
(dm, 4H, J 1.2, CH2-allyl), 4.11 (sm, 4H, CH2-allyl), 5.23 (dt,
2H, J 0.9, 1.2, HC¼), 5.29 (dm, 2H, J 0.9, HC¼). dC (50 MHz,
CDCl3) 45.0 (2 ꢂ ClCH2), 69.6 (2 ꢂ OCH2), 70.5 (2 ꢂ OCH2),
70.6 (2 ꢂ OCH2), 71.2 (2 ꢂ OCH2), 116.6 (2 ꢂ H2C¼), 142.0
(2 ꢂ ¼C) ppm. m/z (EI) 291 (,1 %, [M ꢁ Cl]þ); 221 (12 %);
133 (33 %), 97 (15 %), 91 (33 %), 89 (100 %), 73 (51 %), 55
(29 %). m/z (HRMS) Anal. Calc. for C14H24O435Cl [M ꢁ Cl]þ:
291.1359. Found: 291.1364. Increasing the eluent to 3 : 7
hexanes : EtOAc gave colourless compound 27 (0.62 g, 12 %).
Rf (1 : 1 EtOAc : hexanes) ¼ 0.13. dH (400 MHz, CDCl3) 3.5–3.6
(m, 8H, OCH2), 3.62–3.66 (m, 8H, OCH2), 3.64 (s, 8H, OCH2),
4.00 (dd, 4H, J 1.2, 1.2, CH2-allyl), 4.08 (dm, 4H, J 1.2,
CH2-allyl), 4.09 (d, 4H, J 0.8, CH2-allyl), 5.16 (dd, 2H, J 0.8,
0.8, HC¼), 5.22 (dt, 2H, J 1.2, 1.2, HC¼), 5.27 (dm, 2H, J 1.2,
HC¼). dC (75 MHz, CDCl3) 45.1 (2ꢂ ClCH2), 69.5 (2ꢂ OCH2),
69.7 (2 ꢂ OCH2), 70.5 (2 ꢂ OCH2), 70.6 (2 ꢂ OCH2), 70.7
(2 ꢂ OCH2), 70.8 (2 ꢂ OCH2), 71.2 (2 ꢂ OCH2), 71.8 (2 ꢂ
OCH2), 113.9 (H2C¼), 116.7 (2 ꢂ H2C¼), 142.0 (2 ꢂ ¼C),
142.6 (¼C). m/z (HRMS, ESI) Anal. Calc. for C24H42O8Cl2Na:
551.2154. Found: 551.2172.
(1 mL) was added within 1 s to NaH (0.189 g, 7.9 mmol,
,2.6 equiv.) in anhydrous THF (10 mL). The reaction, under a
vigorous evolution of hydrogen gas, was instantaneous, and the
grey suspension hadturned yellow-white. Thismixture wasstirred
for 15 h at room temperature. This mixture was diluted with THF
(10 mL) and filtered over a bed of silica gel (1 cm). The filter was
further eluted with THF (20 mL) and the filtrate rotary evaporated
dry on a hot waterbath (,908C) to give crude product 14a (1.05 g,
80 %) as a slightly pale-yellow oil.
8,21-Dimethylene-3,6,13,16,23,26-hexaoxa-
10,19-dithiaoctacosa-1,27-diene (14b)
A solution of 2-(vinyloxy)ethanol (20) (1.07 g, 12.1 mmol,
4.0 equiv.) and 2,15-bis(chloromethyl)-7,10- dioxa-4,13-
dithiahexadeca-1,15-diene (28) (1.1 g, 3.1 mmol, 1 equiv.) in
butanone (1 mL) was added to a suspension of potassium car-
bonate (1.5 g, 10.9 mmol) and benzyltriethylammonium chlo-
ride (0.1 g, 0.4 mmol) in butanone (2 mL). The mixture was
stirred at 708C for 24 h. The reaction mixture was diluted with
1 : 1 THF : hexanes (20 mL) and filtered over a bed of silica gel
(3 cm diameter and 2 cm thick). The filter was further eluted
with 1 : 1 THF : hexanes (20 mL) and the clear filtrate rotary
evaporated dry to give 1.46 g crude product as a clear, but vis-
cous oil also containing some 20. Chromatography on silica gel
was carried out by gradient elution from 3 : 7 EtOAc : hexanes to
2 : 3 EtOAc : hexanes and gave the product 14b (0.73 g, 52 %).
Rf (1 : 1 EtOAc : hexane) ¼ 0.49. dH (300 MHz, CDCl3) 2.62 (t,
4H, J 6.9, CH2S), 3.21 (d, 4H, J 0.6, SCH2-allyl), 3.60 (s, 4H,
OCH2), 3.60 (t, 4H, J 6.9, OCH2), 3.64–3.67 (m, 4H, OCH2),
3.81–3.85 (m, 4H, OCH2), 4.00 (dd, 2H, J 6.6, 2.1, H2C¼CH),
4.10 (s, 4H, OCH2), 4.18 (dd, 2H, J 14.4, 2.1, H2C¼CH), 5.06 (d,
2H, J 0.9, H2C¼C), 5.14 (d, 2H, J 1.5, H2C¼C), 6.48 (dd, 2H,
J 14.4, 6.6, H2C¼CH). dC (75 MHz, CDCl3) 30.4 (2 ꢂ SCH2),
34.9 (2 ꢂ SCH2-allyl), 67.3 (2 ꢂ vinyl-OCH2), 68.5 (2 ꢂ
OCH2), 70.3 (2 ꢂ OCH2), 70.7 (2 ꢂ OCH2), 71.9 (2 ꢂ OCH2-
allyl), 86.7 (2 ꢂ ¼CH2), 115.1 (2 ꢂ ¼CH2), 141.6 (2 ꢂ ¼C),
151.8 (2 ꢂ ¼CH-O). m/z (HRMS, ESI) Anal. Calc. for
C22H38O632S2Na: 485.2008. Found: 485.1997. ‘Semi’-alkylated
product 29. Rf (1 : 1 EtOAc : hexane) ¼ 0.45. dH (300 MHz,
CDCl3) 2.57 (t, 2H, J 6.9, SCH2), 2.60 (t, 2H, J 6.9, SCH2), 3.19
(d, 2H, J 0.6, SCH2-allyl), 3.30 (d, 2H, J 0.9, SCH2-allyl), 3.57
(s, 4H, OCH2), 3.57–3.64 (m, 6H, OCH2), 3.81 (m, 2H, OCH2),
3.97 (dd, 1H, J 6.9, 2.1, H2C¼CH), 4.07 (s, 2H, ClCH2), 4.15
(dd, 1H, J 14.4, 2.1, H2C¼CH), 4.17 (dm, 2H, J 0.9, OCH2-
allyl), 5.03 (sm, 1H, H2C¼C), 5.07 (dm, 1H, J 0.9, H2C¼C),
5.12 (dm, 1H, J 1.5, H2C¼C), 5.20 (d, 1H, J 0.9, H2C¼C), 6.46
(dd, 1H, J 14.4, 6.9, H2C¼CH). dC (75 MHz, CDCl3) 30.2
(2 ꢂ SCH2), 34.7 (SCH2-allyl), 34.9 (SCH2-allyl), 45.6
(CH2Cl), 67.3 (OCH2), 68.3 (OCH2), 70.1 (OCH2), 70.2
(OCH2), 70.5 (OCH2), 70.6 (OCH2), 71.7 (OCH2), 86.5
(¼CH2), 115.0 (¼CH2), 117.3 (¼CH2), 140.9 (¼C), 141.4
(¼C), 151.6 (¼CH). m/z (HRMS, ESI) Anal. Calc. for
C18H31O435Cl32S2Na: 433.1250. Found: 433.1228.
8,21-Dimethylene-3,6,10,13,16,19,23,26-
octaoxaoctacosa-1,27-diene (14a)
A solution of 2-(vinyloxy)ethanol (20) (0.7 g, 7.95 mmol,
2.6 equiv.) in butanone (1 mL) was added to a suspension of
potassium carbonate (1.5 g, 10.85 mmol) and benzyl-
triethylammonium chloride as a phase transfer catalyst (0.1 g,
0.44 mmol) in butanone (2 mL). Then 2,15-bis(chloromethyl)-
4,7,10,13-tetraoxahexadeca-1,15-diene (26) (1 g, 3.056 mmol,
1 equiv) was added and the mixture stirred for 18 h at 708C.
Butanone (40 mL) was added and the mixture filtered. The fil-
trate was rotary evaporated dry. The crude product was diluted
with 1 : 1 THF : hexanes (20 mL) and filtered over a bed of silica
gel (3 cm diameter and 2 cm thick). The filter was further eluted
with 1 : 1 THF : hexanes (20 mL) and the clear filtrate rotary
evaporated dry on a hot waterbath (908C) to give 1.07 g crude
product as a clear, but viscous oil (81 %). Chromatography on
silica gel was carried out, and elution with 2 : 3 EtOAc : hexanes
gave compound 14a (0.56 g, 43 %). Rf (1 : 1 EtOAc : hexane) ¼
0.14. dH (300 MHz, CDCl3) 3.54–3.61 (m, 4H), 3.62–3.67 (m,
8H), 3.62 (s, 4H), 3.81 (dd, 4H, J 6.1, 5.4), 3.97 (dd, 2H, J 6.9,
2.1), 4.00 (s, 4H), 4.01 (s, 4H), 4.16 (dd, 2H, J 14.4, 2.1), 5.17 (s,
4H), 6.46 (dd, 2H, J 14.4, 6.9). dC (75 MHz, CDCl3) 67.3
(2 ꢂ OCH2), 68.5 (2 ꢂ OCH2), 69.5 (2 ꢂ OCH2), 70.5 (2 ꢂ
OCH2), 70.6 (2 ꢂ OCH2), 71.7 (2 ꢂ OCH2), 71.8 (2 ꢂ OCH2),
86.6 (2 ꢂ ¼CH2), 114.2 (2 ꢂ ¼CH2), 142.4 (¼C), 151.8
(2 ꢂ¼CH-O). m/z (HRMS, ESI) Anal. Calc. for C22H38O8Na:
453.2464. Found: 453.2448.
S,S0-2,15-Dimethylene-4,7,10,13-tetraoxahexadecane-
1,16-diyl O,O0-Diethyl Dicarbonodithioate (30)
Sodium (1.20 g, 52.2 mmol, 2.1 equiv) was dissolved in anhy-
drous ethanol (40 mL) over 30 min. This solution was then
reacted with carbon disulfide (4.1 g, 53.9 mmol, 2.2 equiv) to
form an ethanolic solution of pale-yellow sodium ethyl xan-
thogenate. After 15 min, 2,15-bis(chloromethyl)-4,7,10,13-
tetraoxahexadeca-1,15-diene (26) (7.9 g, 24.1 mmol) was added
neat to this solution, within 1 min. The solution became slightly
8,21-Dimethylene-3,6,10,13,16,19,23,26-
octaoxaoctacosa-1,27-diene (14a)
A mixture of 2,15-bis(chloromethyl)-4,7,10,13-tetraoxahexadeca-
1,15-diene (26) (1 g, 3.056 mmol, 1 equiv.) and 2-(vinyloxy)
ethanol (20) (0.7g, 7.95mmol, 2.6equiv.) in anhydrous THF

1174
C. M. Moorhoff et al.
warm (,358C) and precipitation of white NaCl slowly occurred
and the reaction mixture was kept stirring overnight at room
temperature. EtOH was rotary evaporated off at 608C to give a
viscous yellow translucent oil. This residue was dissolved in
ethyl acetate (40 mL) to precipitate sodium chloride, and this
was filtered off over a layer of silica gel (2 cm). The filter was
again treated with EtOAc (40 mL) and the combined yellow
filtrate was rotary evaporated dry to give crude yellow oil. This
oil was treated with dichloromethane (30 mL) which precipi-
tated unreacted, excess sodium ethyl xanthogenate. This solu-
tion was filtered over Celite and the resulting filtrate was rotary
evaporated dry to give the yellow xanthate 30 (11.75 g, 98 %).
dH (400 MHz, CDCl3) 1.40 (t, 6H, J 7.2, CH3), 3.55–3.58 (m,
4H, OCH2), 3.63–3.66 (m, 4H, OCH2), 3.66 (s, 4H, OCH2), 3.84
(dm, 4H, J 0.8, CH2-allyl), 4.03 (s, 4H, SCH2-allyl), 4.63 (q, 4H,
J 7.2, OCH2), 5.19 (dm, 2H, J 1.2, H2C¼), 5.23 (dm, 2H, J 0.8,
H2C¼). dC (100 MHz, CDCl3) 13.7 (2 ꢂ CH3), 38.2 (2 ꢂ SCH2-
allyl), 69.5 (2 ꢂ OCH2), 70.0 (2 ꢂ OCH2), 70.7 (2 ꢂ OCH2),
70.6 (2 ꢂ OCH2), 72.8 (2 ꢂ OCH2-allyl), 116.4 (2 ꢂ H2C¼),
140.1 (2 ꢂ ¼C), 214.1 (2 ꢂ C¼S). m/z (HRMS, ESI) Anal. Calc.
for C20H34O632S4Na: 521.1112. Found: 521.1136.
(1.1 g, 48 mmol, 2.2 equiv.) in anhydrous methanol (25 mL)
were synchronously added to anhydrous methanol (20 mL) at
508C within 40 min. After 10 min NaCl started to precipitate and
the mixture was then further stirred for 40 min at 608C. The
reaction mixture was cooled to room temperature and further
stirred for 15 h. Methanol was rotary evaporated off and the
residue was suspended in dichloromethane (50 mL) and filtered
over a bed of silica gel (3 cm) to remove impurities (including
yellow colour) and sodium chloride. The clear solution was then
rotary evaporated dry and gave a viscous, pale-yellow oil (10 g).
This crude product was chromatographed on only 60 g silica gel
and eluted fast with 1 : 5 EtOAc : hexanes and gave after
removal of solvent compound 14c (4.40 g, 43 %). Rf (1 : 1
EtOAc : hexane) ¼ 0.52. dH (300 MHz, CDCl3) 2.69 (t, 4H, J
6.9, SCH2), 3.22 (d, 4H, J 0.9, SCH2-allyl), 3.56–3.63 (m, 4H,
CH2O), 3.63–3.66 (m, 4H, CH2O), 3.63 (s, 4H, CH2O), 3.82 (t,
4H, J 6.9, vinyl-OCH2), 4.01 (dd, 2H, J 6.9, 2.1, CH¼CH2),
4.08 (s, 4H, CH2-allyl), 4.18 (dd, 2H, J 14.4, 2.1, CH¼CH2),
5.05 (dm, 2H, J 0.9, C¼CH2), 5.14 (dm, 2H, J 1.2, C¼CH2),
6.43 (dd, 2H, J 14.4, 6.9, CH¼CH2). dC (75 MHz, CDCl3) 29.8
(2 ꢂ SCH2), 34.9 (2 ꢂ SCH2-allyl), 67.3 (2 ꢂ vinyl-OCH2), 69.6
(2 ꢂ OCH2), 70.6 (2 ꢂ OCH2), 70.7 (2 ꢂ OCH2), 71.7 (2 ꢂ
OCH2-allyl), 87.0 (2 ꢂ ¼CH2), 115.0 (2 ꢂ ¼CH2), 141.7
(2 ꢂ ¼C), 151.4 (2 ꢂ ¼CH-O). m/z (HRMS, ESI) Anal. Calc.
for C22H38O632S2Na: 485.2008. Found: 485.2001.
2,15-Dimethylene-4,7,10,13-tetraoxahexadecane-
1,16-dithiol (31)
CAUTION: Workup of the reaction-mixture should be carried
out in a fume-hood, since by-products may have a severe stench.
S,S0-2,15-Dimethylene-4,7,10,13-tetraoxahexadecane-1,16-
diyl O,O0-diethyl dicarbonodithioate (30) (22.0 g, 44.1 mol) was
added neat to ethylenediamine (6 mL, 5.4 g, 89.8 mmol,
2.04 equiv) over a period of 25 min at 08C and then stirred for
a further 35 min at 08C and then subsequently allowed to come to
room temperature and stirred for another 15 min. This reaction
mixture was added to a premixed solution of conc. H2SO4
(10 mL, 18.4 g, 187.8 mmol) and 40 g crushed ice in a small
beaker with fast magnetic stirring to neutralise ethylene diamine
(followed by checking the pH). The yellow, opaque aqueous
acidic layer was treated with dichloromethane (30 mL) and
hexanes (10 mL). This mixture was transferred to a funnel and
extracted. The organic layer was then isolated and treated with
saturated NaHCO3 solution (40 mL). All aqueous extractions
were again extracted with dichloromethane (30 mL). The com-
bined organic layer was dried (Na2SO4) for 15 min and filtered
over silica gel and further eluted with dichloromethane. The
filtrate was rotary evaporated at 408C to give a crude oil (10.2 g,
72 %) of dimercaptan 31. This oil was then chromatographed on
silica gel (60 g) with 1 : 4 EtOAc : hexanes. After some minor
amounts of very smelly sulfurous fractions, near odourless
compound 31 (7.5 g, 53 %) was isolated pure. Rf (1 : 1 EtOAc :
hexanes) ¼ 0.36. dH (300 MHz, CDCl3) 1.51 (t, 2H, J 8.1, SH),
3.20 (dd, 4H, J 8.1, 1.2, CH2SH), 3.54–3.58 (m, 4H, OCH2),
3.63–3.65 (m, 4H, OCH2), 3.64 (s, 4H, OCH2), 4.10 (s, 4H,
OCH2-allyl), 5.04 (d, 2H, J 1.2, ¼CH), 5.11 (d, 2H, J 0.6, ¼CH).
dC (75 MHz, CDCl3) 27.1 (2 ꢂ CH2S), 69.4 (2 ꢂ CH2O), 70.6
(2 ꢂ CH2O), 70.7 (2 ꢂ CH2O), 72.0 (2 ꢂ CH2O), 113.8 (2 ꢂ
CH2¼), 145.2 (2 ꢂ C¼). m/z (HRMS, ESI). Anal. Calc. for
C14H26O432S2Na: 345.1170. Found: 345.1170.
S,S0-2,15-Dimethylene-7,10-dioxa-4,13-dithiahexadecane-
1,16-diyl O,O0-Diethyl Dicarbonodithioate (32)
Sodium (1.65 g, 71.7 mmol, 2.2 equiv) was dissolved in anhy-
drous ethanol (40 mL) within 30 min, and this solution was then
reacted with carbon disulfide (5.7 g, 75 mmol, 2.2 equiv) to form
a solution of pale-yellow sodium ethyl xanthogenate. After
15min, 2,15-bis(chloromethyl)-7,10-dioxa-4,13-dithiahexadeca-
1,15-diene (28) (12 g, 33.4 mmol) in anhydrous THF (20 mL)
was added to this solution within 3 min and the solution tem-
perature increased slightly (,358C). Precipitation of white
NaCl slowly occurred and the reaction mixture was kept stirring
overnight at room temperature. Ethanol and THF were rotary
evaporated off at 608C to give a viscous yellow translucent oil.
This residue was dissolved in EtOAc (40 mL) and the precipi-
tated NaCl was filtered off over a layer of silica gel (2 cm). The
filter was again treated with EtOAc (40 mL) and the combined
yellow filtrate was rotary evaporated dry to give crude yellow
oil. This oil was treated with dichloromethane (30 mL) which
precipitated unreacted, excess sodium ethyl xanthogenate. This
solution was filtered over a layer of Celite (0.5 cm). The yellow
filtrate was rotary evaporated dry to give compound 32 (17.1 g,
97 %). dH (300 MHz, CDCl3) 1.42 (t, 6H, J 7.2, CH3), 2.62 (t,
4H, J 6.9, SCH2), 3.26 (dm, 4H, J 1.2, SCH2-allyl), 3.60 (s, 4H,
OCH2), 3.63 (t, 4H, J 6.9, OCH2), 3.95 (dm, 4H, J 1.2, CH2-
allyl), 4.64 (q, 4H, J 7.2, OCH2), 5.07 (dm, 2H, J 1.2 Hz, H2C¼),
5.19 (dm, 2H, J 1.2, H2C¼). dC (75 MHz, CDCl3) 13.8 (2 ꢂ
CH3), 30.4 (2 ꢂ SCH2), 37.0 (2 ꢂ SCH2-allyl), 39.1 (2 ꢂ SCH2-
allyl), 70.1 (2 ꢂ OCH2), 70.3 (2 ꢂ OCH2), 70.7 (2 ꢂ OCH2),
117.3 (2 ꢂ H2C¼), 139.1 (2 ꢂ ¼C), 213.9 (2 ꢂ C¼S). m/z
(HRMS, ESI). Anal. Calc. for C20H34O432S6Na: 553.0679.
Found: 553.0653.
8,21-Dimethylene-3,10,13,16,19,26-hexaoxa-
6,23-dithiaoctacosa-1,27-diene (14c)
2,15-Dimethylene-7,10-dioxa-4,13-dithiahexadecane-
1,16-dithiol (33)
A mixture of 2,15-dimethylene-4,7,10,13-tetraoxahexadecane-
1,16-dithiol (31) (7.2 g, 22.2 mmol) and 2-chloroethyl vinyl
ether (6) (5.50 g, 51.6 mmol, 2.3 equiv.) in anhydrous methanol
(to fill a syringe to 25 mL) and a solution of pre-reacted sodium
CAUTION: Workup of the reaction-mixture should be carried
out in a fume-hood, since by-products may have a severe stench.

(Alkane-a,v-diyl)(bis[3,30-allyl dithioethers]) Monomer
1175
S,S0-2,15-dimethylene-7,10-dioxa-4,13-dithiahexadecane-
1,16-diyl-O,O0-diethyl dicarbonodithioate (32) (17.0 g,
32.0 mol) was added neat to ethylenediamine (6 mL, 5.4 g,
90 mmol, 2.8 equiv) over a period of 20 min at 08C and then
further stirred for 30 min at 08C and then allowed to come to
room temperature and stirred for a further 15 min until the
yellow xanthate colour had disappeared. This reaction mixture
was added all at once to a premixed solution of conc. H2SO4
(10 mL, 18.4 g, 188 mmol) and 40 g crushed ice in a small beaker
with rapid stirring to neutralise ethylene diamine (pH was
checked). The yellow, opaque aqueous acidic layer was treated
with dichloromethane (30 mL), followed by the addition of
hexanes (10 mL) and stirred. This mixture was transferred to a
funnel and extracted. The aqueous layer was once more
extracted with 3 : 1 dichloromethane : hexanes (40 mL). The
combined organic layer was then treated with a saturated
NaHCO3 solution (50 mL), separated and then dried (Na2SO4)
for 15 min. Filtration over silica gel (4 cm layer) and further
elution with dichloromethane (50 mL) gave a colourless filtrate.
The filtrate was rotary evaporated to give a sulfurous smelling
crude oil. This oil was then chromatographed on silica gel (60 g)
and chromatographed as speedily as possible with 1 : 9 EtOAc :
hexanes to curb decomposition of the wanted dimercaptan 33.
After some minor amounts of very smelly sulfurous fractions the
colourless dimercaptan 33 (7.62 g, 72 %) was isolated. Rf (1 : 1
EtOAc : hexanes) ¼ 0.54. dH (300 MHz, CDCl3) 1.50 (t, 2H,
J 8.4, SH), 2.59 (t, 4H, J 6.3, SCH2), 3.29 (dd, 4H, J 8.4, 1.2,
CH2SH), 3.34 (d, 4H, J 1.2, SCH2-allyl), 3.58 (s, 4H, CH2O),
3.60 (t, 4H, J 6.3, OCH2), 4.92 (d, 2H, J 1.2, ¼CH), 5.06 (dt, 2H,
J 1.2, 1.2, ¼CH). dC (75 MHz, CDCl3) 27.9 (2 ꢂ CH2SH), 30.3
(2 ꢂ ¼CCH2S), 35.9 (2 ꢂ SCH2), 70.3 (2 ꢂ CH2O), 70.6 (2 ꢂ
CH2O), 114.6 (2 ꢂ CH2¼), 144.1 (2 ꢂ C¼). m/z (HRMS, ESI).
Anal. Calc. for C14H26O232S4Na: 377.0713. Found: 377.0717.
116.1 (2 ꢂ ¼CH2), 140.8 (2 ꢂ ¼C), 151.4 (2 ꢂ ¼CH-O). m/z
(HRMS, ESI) Anal. Calc. for C22H38O432S4Na: 517.1551.
Found: 517.1526.
S,S0-2,15,28-Trimethylene-7,10,20,23-tetraoxa-
4,13,17,26-tetrathianonacosane-1,29-diyl
O,O0-Diethyldicarbonodithioate (35)
Sodium (0.50 g, 21.7 mmol, 2.2 equiv.) was dissolved in anhy-
drous ethanol (20 mL) within 30 min, and this solution was then
reacted with carbon disulfide (1.9 g, 25.0 mmol, 2.5 equiv) to
form an ethanolic solution of pale-yellow sodium ethyl
xanthogenate. Anhydrous THF (20 mL) was added. Then,
after 20 min, 2,28-bis(chloromethyl)-15-methylene-7,10,20,23-
tetraoxa-4,13,17,26-tetrathianonacosa-1,28-diene (34) (6.0 g,
10.11 mmol) in anhydrous THF (10 mL) was added neat to this
solution within 1 min and the solution became slightly warm
(358C). Precipitation of white NaCl occurred slowly and the
reaction mixture was kept stirring overnight at room tempera-
ture. The solvents were rotary evaporated off at 608C to give a
viscous, yellow translucent oil. This residue was dissolved in
ethyl acetate (20 mL) and the precipitated NaCl was filtered off
over a layer silica gel. The filter was again treated with ethyl
acetate (20 mL) and the combined yellow filtrate was rotary
evaporated dry to give a crude yellow oil. This oil was treated
with dichloromethane (15 mL) which precipitated unreacted,
excess sodium ethyl xanthogenate. This solution was filtered
over a sintered glass funnel having a layer of Celite (0.5 cm).
The filtrate was rotary evaporated dry and further evacuated to
give yellow compound 35 (7.45 g, 96 %). dH (300 MHz, CDCl3)
1.42 (t, 6H, J 7.2, CH3), 2.61 (t, 4H, J 6.9, SCH2), 2.62 (t, 4H, J
6.6, SCH2), 3.26 (d, 4H, J 0.9, SCH2-allyl), 3.31 (s, 4H, SCH2-
allyl), 3.60 (s, 8H, OCH2), 3.62 (t, 4H, J 6.9, OCH2), 3.63 (t, 4H,
J 6.6, OCH2), 3.95 (d, 4H, J 0.9, SCH2), 4.64 (q, 4H, J 7.2,
OCH2), 5.00 (s, 2H, H2C¼) 5.07 (s, 2H, H2C¼), 5.19 (d, 2H,
J 1.2, H2C¼). dC (100 MHz, CDCl3) 13.8 (2 ꢂ CH3), 30.3
(2 ꢂ SCH2), 30.4 (2 ꢂ SCH2), 35.7 (2 ꢂ SCH2-allyl), 37.1
(2 ꢂ SCH2-allyl), 39.1 (2 ꢂ SCH2), 70.0 (2 ꢂ OCH2), 70.3
(2 ꢂ OCH2), 70.4 (2 ꢂ OCH2), 70.6 (2 ꢂ OCH2), 70.7 (2 ꢂ
OCH2), 116.0 (H2C¼), 117.3 (2 ꢂ H2C¼), 139.1 (2 ꢂ ¼C),
140.9 (¼C), 213.8 (2 ꢂ C¼S) ppm. m/z (HRMS, ESI) Anal.
Calc. for C30H52O632S8Na: 787.1427. Found: 787.1415.
8,21-Dimethylene-3,13,16,26-tetraoxa-6,10,19,23-
tetrathiaoctacosa-1,27-diene (14d)
A mixture of 2,15-dimethylene-7,10-dioxa-4,13-dithiahexadecane-
1,16-dithiol (33) (7.62 g, 21.5 mmol) and 2-chloroethyl vinyl
ether (6) (5.45 g, 51.2 mmol, 2.4 equiv.) in anhydrous methanol
(to fill a syringe to exactly 20 mL) and a solution of pre-reacted
sodium (1.11 g, 48.3 mmol, 2.3 equiv.) in anhydrous methanol
(20 mL) were synchronously added to anhydrous methanol
(5 mL) at 508C within 40 min. After 10 min sodium chloride
started toprecipitate. The reaction mixture was further stirred for
40 min at 608C and then cooled to room temperature and stirred
overnight for 15 h. Methanol was rotary evaporated off and the
residue was suspended in dichloromethane (50 mL) and filtered
over a bed of silica gel (3 cm) to remove impurities and sodium
chloride. The clear solution was then rotary evaporated dry and
gave a viscous, pale-yellow oil (8.5 g). This crude product was
chromatographed on only 60 g silica gel and eluted fast with 1 : 9
EtOAc : hexanes to give after removal of solvent compound 14d
(4.40 g, 43 %). Rf (1 : 1 EtOAc : hexane) ¼ 0.63. White solid, m.
p. 358C. dH (300 MHz, CDCl3) 2.61 (t, 4H, J 6.9, SCH2), 2.68
(t, 4H, J 6.6, SCH2), 3.32 (s, 4H, SCH2-allyl), 3.33 (d, 4H, J 0.6,
SCH2-allyl), 3.60 (s, 4H, OCH2), 3.62 (t, 4H, J 6.9, OCH2),
3.82 (t, 4H, J 6.6, OCH2), 4.01 (dd, 2H, J 6.9, 2.1, CH¼CH2),
4.18 (dd, 2H, J 14.4, 2.1, CH¼CH2), 5.01 (sm, 2H, C¼CH2),
5.02 (sm, 2H, C¼CH2), 6.43 (dd, 2H, J 14.4, 6.9, CH¼CH2).
dC (75 MHz, CDCl3) 29.8 (2 ꢂ SCH2-allyl), 30.4 (2 ꢂ SCH2),
35.7 (2 ꢂ SCH2-allyl), 35.8 (2 ꢂ SCH2-allyl), 67.3 (2 ꢂ vinyl-
OCH2), 70.3 (2 ꢂ OCH2), 70.7(2ꢂ OCH2), 87.0 (2 ꢂ HC¼CH2),
2,15,28-Trimethylene-7,10,20,23-tetraoxa-4,13,17,26-
tetrathianonacosane-1,29-dithiol (36)
CAUTION: Workup of the reaction-mixture should be carried
out in a fume-hood, since by-products may have a severe stench.
S,S0-2,15-dimethylene-4,7,10,13-tetraoxahexadecane-1,16-
diyl-O,O0-diethyl dicarbonodithioate (35) (7.5 g, 9.80 mmol)
was added neat to ethylenediamine (1.5 mL, 1.35 g, 22.5 mmol,
2.3 equiv) over a period of 7 min at 08C and was then further
stirred with a strong magnetic stirrer bar (viscous mixture) for
35 min at 08C and then allowed to come to room temperature and
stirred for another 30 min. This reaction mixture was added all at
once to a premixed solution of conc. H2SO4 (2.5 mL, 4.6 g,
47 mmol) and 20 g crushed ice in a small beaker with fast
magnetic stirring to neutralise ethylene diamine (checked by
pH). The yellow, opaque aqueous acidic layer was treated with
dichloromethane (40 mL) and vigorously stirred. This mixture
was transferred to a funnel and extracted. The organic layer was
then isolated and treated with saturated NaHCO3 solution
(40 mL). All aqueous extractions were again extracted with
dichloromethane (30 mL). The combined organic layer was

1176
C. M. Moorhoff et al.
dried (Na2SO4) for 15 min and filtered over silica gel and further
eluted with dichloromethane (30 mL) and then ethyl acetate
(50 mL). The combined filtrate was rotary evaporated at 408C to
give a crude oil. This oil was then chromatographed on silica gel
(60 g) as speedily as possible with 1 : 4 EtOAc : hexanes to curb
decomposition of the desired dimercaptan 36. After some minor
amounts of very smelly sulfurous fore-fractions, odourless
compound 36 (2.33 g, 40 %) was isolated as a viscous oil at
room temperature, but crystallizing below 108C as a white solid.
Rf (1 : 1 EtOAc : hexane) ¼ 0.52. dH (300 MHz, CDCl3) 1.50 (t,
2H, J 8.1, SH), 2.60 (t, 4H, J 6.6, CH2S), 2.61 (t, 4H, J 6.9 Hz,
CH2S), 3.30 (dd, 4H, J 8.1, 1.2, CH2SH), 3.31 (s, 4H, SCH2-
allyl), 3.35 (d, 4H, J 0.9, SCH2-allyl), 3.59 (s, 8H, OCH2), 3.61
(t, 4H, J 6.6, OCH2), 3.62 (t, 4H, J 6.9, OCH2), 4.93 (d, 2H, J 0.9,
¼CH), 4.99 (s, 2H, ¼CH), 5.06 (d, 2H, J 1.2 Hz, ¼CH). dC
(50 MHz, CDCl3) 27.9 (2 ꢂ CH2SH), 30.3 (2 ꢂ SCH2), 30.4
(2 ꢂ SCH2), 35.7 (2 ꢂ SCH2-allyl), 35.8 (2 ꢂ SCH2-allyl),
70.3 (4 ꢂ OCH2), 70.6 (2 ꢂ OCH2), 70.7 (2 ꢂ OCH2), 114.7
(2 ꢂ ¼CH2), 115.9 (¼CH2), 140.9 (¼C), 144.1 (2 ꢂ ¼C). m/z
(HRMS, ESI). Anal. Calc. for C24H44O432S6Na: 611.1462.
Found: 611.1433.
J 6.9, OCH2), 3.82 (t, 4H, J 6.9, OCH2), 4.01 (dd, 2H, J 6.9, 2.1,
CH¼CH2), 4.18 (dd, 2H, J 14.4, 2.1, CH¼CH2), 4.99 (sm, 2H,
C¼CH2), 5.01 (s, 2H, C¼CH2), 5.02 (s, 2H, C¼CH2), 6.44 (dd,
2H, J 14.4, 6.9, CH¼CH2). dC (75 MHz, CDCl3) 29.8 (2 ꢂ
SCH2), 30.3 (2 ꢂ SCH2), 30.4 (2 ꢂ SCH2), 35.6 (2 ꢂ SCH2-
allyl), 35.7 (2 ꢂ SCH2-allyl), 35.8 (2 ꢂ SCH2-allyl), 67.3 (2 ꢂ
OCH2), 70.3 (4 ꢂ OCH2), 70.6 (2 ꢂ CH2O), 70.7 (2 ꢂ CH2O),
87.0 (2 ꢂ ¼CH2), 116.0 (¼CH2), 116.1 (2 ꢂ ¼CH2), 140.8
(2 ꢂ ¼C), 140.9 (¼C), 151.4 (2 ꢂ ¼CH-O). m/z (HRMS, ESI).
Anal. Calc. for C32H56O632S6Na: 751.2299. Found: 751.2277.
Supplementary Material
1H and 13C spectra and Rf chromatography values are available
on the Journal’s website.
Acknowledgements
The authors wish to acknowledge the support of ARC DP0877382 in
this work.
References
[1] C. M. Moorhoff, W. D. Cook, F. Chen, D. Nghiem, C. Braybrook,
S. Thang, J. Sun, T. F. Scott, C. N. Bowman, Aust. J. Chem. 2011, 64,
1083. doi:10.1071/CH11117
Note: This compound does not dissolve in methanol, but
dissolves very well in THF.
[2] W. D. Cook, F. Chen, Q. D. Nghiem, T. F. Scott, C. N. Bowman,
S. Chausson, L. Le Pluart, Macromol. Symp. 2010, 291, 50.
doi:10.1002/MASY.201050507
8,21,34-Trimethylene-3,13,16,26,29,39-hexaoxa-
6,10,19,23,32,36-hexathia-hentetraconta-1,40-diene (37)
[3] W. D. Cook, S. Chausson, F. Chen, L. Le Pluart, C. N. Bowman,
T. F. Scott, Polym. Int. 2008, 57, 469. doi:10.1002/PI.2357
[4] T. F. Scott, A. D. Schneider, W. D. Cook, C. N. Bowman, Science
2005, 308, 1615. doi:10.1126/SCIENCE.1110505
[5] W. D. Cook, M. Forrest, A. A. Goodwin, Dent. Mat. 1999, 15, 447.
doi:10.1016/S0109-5641(99)00073-1
[6] R. E. Evans, E. Rizzardo, Macromolecules 2000, 33, 6722.
doi:10.1021/MA9917646
[7] R. E. Evans, E. Rizzardo, J. Polym. Sci. Pol. Chem. 2001, 39, 202.
doi:10.1002/1099-0518(20010101)39:1,202::AID-POLA230.3.0.
CO;2-6
A mixture of 2,15,28-trimethylene-7,10,20,23-tetraoxa-
4,13,17,26-tetrathianonacosane-1,29-dithiol (36) (2.33 g,
4.0 mmol) and 2-chloroethyl vinyl ether (6) (1.00 g, 9.4 mmol,
2.4 equiv) in anhydrous methanol (2 mL) and anhydrous THF
(3 mL) (total volume to 7 mL) and a solution of pre-reacted
sodium (0.20 g, 8.7 mmol, 2.2equiv.) in anhydrous methanol
(7 mL) were synchronously added to anhydrous THF (3 mL) at
508C within 40 min and was then further stirred for 45 min at
608C. The reaction mixture was cooled to room temperature and
stirred overnight for 15 h. Methanol was rotary evaporated off
and the residue was suspended in dichloromethane (50 mL) and
filtered over a bed of silica gel (3 cm) to remove impurities and
NaCl. The colourless solution was then rotary evaporated dry
and gave a viscous, pale-yellow oil (3 g). This crude was chro-
matographed on 60 g silica gel and eluted with 1 : 5 EtOAc :
hexanes to give after removal of solvent a colourless solid of
compound 37 (1.07 g, 39 %). Rf (1 : 1 EtOAc : hexane) ¼ 0.61.
m.p. 428C. dH (300 MHz, CDCl3) 2.61 (t, 4H, J 6.9, SCH2), 2.62
(t, 4H, J 6.9, SCH2), 2.68 (t, 4H, J 6.9, SCH2), 3.31 (s, 4H, SCH2-
allyl), 3.32 (d, 4H, J 0.3, SCH2-allyl), 3.34 (d, 4H, J 0.6, SCH2-
allyl), 3.60 (s, 8H, OCH2), 3.61 (t, 4H, J 6.9, OCH2), 3.62 (t, 4H,
[8] T. F. Scott, R. B. Draughon, C. N. Bowman, Adv. Mater. 2006, 18,
2128. doi:10.1002/ADMA.200600379
[9] C. J. Kloxin, T. F. Scott, C. N. Bowman, Macromolecules 2009, 42,
2551. doi:10.1021/MA802771B
[10] L. Pauling, The Nature of the Chemical Bond 1960, 3rd edn (Cornell
University: New York, NY).
[11] L. C. Allen, J. Am. Chem. Soc. 1989, 111, 9003. doi:10.1021/
JA00207A003
[12] K. Nishide, S.-i. Ohsugi, T. Miyamoto, K. Kumar, M. Node, Monatsh.
Chem. 2004, 135, 189. doi:10.1007/S00706-003-0122-1
[13] G. Socrates, Infrared and Raman Characteristic Group Frequencies:
Tables and Charts 2008, 3rd edn (John Wiley and Sons: Sussex).