Macromolecules, Vol. 37, No. 11, 2004
Si-Containing Poly(diarylacetylene)s 4105
Sch em e 1. Syn th esis of Si-Con ta in in g P oly(d ia r yla cetylen e)s a n d P r ep a r a tion of P oly(d ia r yla cetylen e)
Mem br a n es
Sch em e 2. Syn th esis of Mon om er s 1c-f
1-[(p-Tr im eth ylsilyl)p h en yl]-2-(2-flu or en yl)a cetylen e
(1c). A 500 mL three-necked flask was equipped with a reflux
condenser, a three-way stopcock, and a magnetic stirring bar
and was flushed with dry nitrogen. 2-Bromofluorene (5.0 g,
20 mmol), bis(triphenylphosphine)palladium dichloride (56 mg,
0.080 mmol), cuprous iodide (93 mg, 0.48 mmol), triph-
enylphosphine (85 mg, 0.32 mmol), and triethylamine (150 mL)
were placed in the flask. Then, 4-trimethylsilyl-1-ethynylben-
zene (4.4 g, 25 mmol) in triethylamine (50 mL) solution was
added. The reaction mixture was heated at reflux temperature
for 5 h. After the triethylamine in the reaction mixture was
evaporated, diethyl ether (ca. 300 mL) was added, and the
insoluble salt was filtered off. The filtrate was washed at first
with 1 N hydrochloric acid and then with water. The ethereal
solution was dried over anhydrous sodium sulfate and then
concentrated at reduced pressure. Purification of the crude
product by flash column chromatography (eluent: hexane)
provided the desired product (4.9 g, 71%) as a white solid; mp
158.0-159.0 °C, purity >99% (1H NMR). IR (KBr): 2957, 1595,
1-[(p-Tr im eth lsilyl)ph en yl]-2-(4-biph en yl)acetylen e (1e).
This monomer was prepared from 4-iodobiphenyl in the same
way as for 1c. Yield 75%, mp 123.0-125.0 °C, purity >99%
(1H NMR). IR (KBr): 2955, 1595, 1483, 1252, 1101, 858, 839,
764 cm-1. 1H NMR (CDCl3, δ): 7.63-7.57 (m, 6H, Ar), 7.52 (s,
4H, Ar), 7.45 (t, 2H, Ar), 7.36 (t, 1H, Ar), 0.30 ppm (s, 9H). 13
C
NMR (CDCl3, δ): 141.0, 140.9, 140.3, 133.2, 132.0, 131.9, 130.6,
128.8, 127.6, 127.0, 123.5, 122.1, 90.2, 89.7, -1.3 ppm. Anal.
Calcd for C23H22Si: C, 84.6%; H, 6.8%; Si, 8.6%. Found: C,
84.5%; H, 6.8%; Si, 8.7%.
1-[(p-Tr im eth ylsilyl)ph en yl]-2-(2-an th r yl)acetylen e (1f).
This monomer was prepared similarly to 1c from 2-iodo-
anthracene. Yield 60%, mp 212.0-214.0 °C, purity >99% (1H
NMR). IR (KBr): 2957, 1595, 1458, 1250, 1098, 855, 839, 820,
756 cm-1 1H NMR (CDCl3, δ): 8.40 (s, 2H, Ar), 8.22 (s, 1H,
.
Ar), 8.01-7.95 (m, 3H, Ar), 7.58-7.46 (m, 7H), 0.31 ppm (s,
9H). 13C NMR (CDCl3, δ): 141.2, 133.3, 132.2, 132.1, 131.9,
131.1, 130.7, 128.3, 128.2, 127.7, 126.3, 126.2, 125.8, 125.7,
124.2, 123.5, 120.0, 113.3, 90.5, 89.8, -1.2 ppm. Anal. Calcd
for C25H22Si: C, 85.7%; H, 6.3%; Si, 8.0%. Found: C, 85.5%;
H, 6.4%; Si, 8.1%.
1
1454, 1248, 1198, 1102, 851, 814, 756 cm-1. H NMR (CDCl3,
δ): 7.79-7.71 (m, 2H, Ar), 7.58-7.46 (m, 7H, Ar), 7.38-7.30
(m, 2H, Ar), 3.88 (s, 2H), 0.30 ppm (s, 9H). 13C NMR (CDCl3,
δ): 143.5, 143.1, 141.8, 141.0, 140.8, 133.2, 130.6, 130.5, 128.2,
127.1, 126.9, 125.0, 123.7, 121.2, 120.2, 119.8, 90.5, 89.5, 36.7,
-1.2 ppm. Anal. Calcd for C24H22Si: C, 85.2%; H, 6.6%; Si,
8.2%. Found: C, 85.0%; H, 6.7%; Si, 8.3%.
1-[(p -Tr im et h ylsilyl)p h en yl]-2-(2-p h en a n t h r yl)a cet y-
len e (1d ). This monomer was prepared by the same method
as for 1c by using 4-trimethylsilyl-1-bromobenzene and 2-ethy-
nylphenanthrene instead of 2-bromofluorene and 4-trimeth-
ylsilyl-1-ethynylbenzene as starting materials. Yield 65%, mp
>230 °C, purity 99% (1H NMR). IR (KBr): 2957, 1595, 1462,
1250, 1105, 857, 845, 818, 758 cm-1. 1H NMR (CDCl3, δ): 8.67
(dd, 2H, Ar), 8.10 (s, 1H, Ar), 7.88 (d, 1H, Ar), 7.51-7.78 (m,
9H, Ar), 0.30 ppm (s, 9H). 13C NMR (CDCl3, δ): 141.1, 133.3,
132.2, 131.8, 131.7, 130.7, 129.9, 129.8, 129.3, 128.6, 127.6,
127.5, 127.0, 126.8, 126.5, 123.5, 122.8, 121.3, 90.3, 89.9, -1.2
ppm. Anal. Calcd for C25H22Si: C, 85.7%; H, 6.3%; Si, 8.0%.
Found: C, 85.4%; H, 6.2%; Si, 8.4%.
P olym er iza tion . Polymerizations were performed in a
Schlenk tube equipped with a three-way stopcock under dry
nitrogen. Unless otherwise specified, the polymerizations were
carried out at 80 °C for 24 h under the following conditions:
[M]0 ) 0.10 M, [TaCl5] ) 20 mM, [n-Bu4Sn] ) 40 mM. A
detailed procedure of polymerization is as follows: A monomer
solution was prepared in a Schlenk tube by mixing monomer
1c (0.34 g) and toluene (5.0 mL). Another Schlenk tube was
charged with TaCl5 (71 mg), n-Bu4Sn (0.13 mL), and toluene
(4.9 mL); this catalyst solution was aged at 80 °C for 10 min.
Then the monomer solution was added to the catalyst solution.
Polymerization was carried out at 80 °C for 24 h, which was
quenched with a small amount of methanol. The formed
polymer was isolated by precipitation into a large excess of
methanol, and its yield was determined by gravimetry.
Mem br a n e F a br ica tion a n d Desilyla tion . Membranes
(thickness ca. 30-50 µm) of 2c and 2d were fabricated by
casting toluene solution of the polymers (concentration ca. 1.0-