spectra were obtained with the use of a VARIAN-Cary 500 UV-
Vis spectrophotometer. Fluorescence emission spectra were
obtained with the use of a VARIAN Cary Eclipse luminescence
spectrometer.
dried toluene was added into thꢂe mixture. The reaction was
conducted for another 72 h at 60 C under argon. The reaction
mixture was poured into 30 mL of chloroform and washed with
water (20 mL ꢀ 2) and brine (20 mL ꢀ 2), dried over anhydrous
magnesium sulfate, filtered and concentrated the solution and
precipitated with 30 mL of methanol. The precipitation proce-
dure was repeated three times to remove low molecular weight
1,3,5-Tris(2-methyl-2-hydroxy-3-butynyl)-benzene (1)
1,3,5-Tribromobenzene (2 g, 6 mmol), CuI (102 mg, 0.5 mmol),
Pd(PPh3)4 (350 mg, 0.5 mmol) and 2-methylbut-3-yn-2-ol (2.4 g,
28 mmol) were vigorously refluxed for 4 h (monitored by TLC) in
Et3N (30 mL) under argon, then filtered, removing the solvent in
the filtrate. The residue was purified by flash chromatography on
a silica gel column, eluting with hexane/ethyl acetate (1 : 1),
1
oligomers. A red solid was obtained (223 mg, 52%). H NMR
(400 MHz, CDCl3) d 0.55–0.82 (m, –CH3), 7.00–7.17 (m, Ph–H),
7.29–7.45 (m, Ph–H), 7.49–7.68 (m, Ph–H). GPC (THF): Mw
15 539, Mn ¼ 15 178.
¼
1
Linear conjugated polysilole (7)
providing 1 as a pale yellow solid (1.62 g, 83%). H NMR (400
MHz, CDCl3) d 1.59 (s, 18H), 7.39 (s, 3H).
1,4-Diethynylbenzene (157 mg, 1.2 mmol), CuI (14 mg, 0.072
mmol), Pd(PPh3)2Cl2 (51 mg, 0.072 mmol) and 2,5-dibromo-1,1-
dimethyl-3,4-diphenyl-silole (523 mg, 1.2 mmol) were stirring at
60 ꢂC in 4 mL Et3N and 15 mL toluene for 3 h. After that,
a solution of phenylacetylene (12 mg, 0.12 mmol) in 5 mL of
dried toluene was added into the mixture. The reaction was
conducted for another 12 h at 60 ꢂC under an argon atmosphere.
Then the reaction mixture was poured into 30 mL of chloroform
and washed with water (20 mL ꢀ 2) and brine (20 mL ꢀ 2), dried
over anhydrous magnesium sulfate concentrated the solution
and precipitated with 30 mL of methanol. The precipitation
procedure was repeated three times to remove low molecular
weight oligomers. A red solid was collected by vacuum filtration
1,3,5-Triethynylbenzene (2)
To a solution of 1 (1 g, 3 mmol) in toluene (20 mL) finely
powdered KOH (504 mg, 9 mmol) was added. The mixture was
refluxed for 3 h until no acetone escaped from the reaction
mixture, cooled to room temperature, filtered, and the solvent
removed in the filtrate. The residue was purified by flash chro-
matography on a silica gel column, eluting with hexane,
1
providing 2 as a colorless solid (324 mg, 72%). H NMR (400
MHz, CDCl3) d 3.15 (s, 3H), 7.57 (s, 3H).
1,4-Di(2-methyl-2-hydroxy-3-butynyl)-benzene (3)
1
(103 mg, 22%). H NMR (400 MHz, CDCl3) d 0.48–0.88 (m,
1,4-Dibromobenzene (2 g, 8 mmol), CuI (91 mg, 0.48 mmol), Pd
(PPh3)4 (337 mg, 0.48 mmol) and 2-methylbut-3-yn-2-ol (2 g, 24
mmol) were vigorously refluxed in Et3N (30 mL) for 4 h (moni-
tored by TLC) and then filtered, removing the solvent in the
filtrate. The residue was purified by flash chromatography on
a silica gel column, eluting with hexane/ethyl acetate (1 : 1),
–CH3), 7.05–7.15 (m, Ph–H), 7.20–7.45 (m, Ph–H). GPC (THF):
Mw ¼ 18 867, Mn ¼ 8200.
Acknowledgements
This work was supported by National Natural Science Foun-
dation of China (No. 20872035, 21076078), Specialized Research
Fund for the Doctoral Program of Higher Education (No.
20070251018).
1
providing 3 as a light yellow solid (1.84 g, 95%). H NMR (400
MHz, CDCl3) d 1.61 (s, 12H), 2.05 (s, 2H), 7.34–7.35 (m, 4H).
1,4-Diethynylbenzene (4)
References
To a solution of 1 (1.5 g, 6 mmol) in toluene (20 mL) finely
powdered KOH (672 mg, 12 mmol) was added. The mixture was
refluxed for 3 h until no acetone escaped from the reaction
mixture, cooled to room temperature, filtered, and the solvent
removed in the filtrate. The residue was purified by flash chro-
matography on a silica gel column, eluting with hexane,
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This journal is ª The Royal Society of Chemistry 2012