Letter
NJC
such as specific color tuning in the field of OLEDs, new strategies Acknowledgements
for device processing, etc. Further experimental and photophysical
We gratefully thank H. Wutzel for performing GPC measure-
investigations are currently performed to analyze this effect and to
prove the general applicability of this approach. Determination of
quantum yields using an Ulbricht sphere afforded similar values of
13% and 15% for polymers 8 and 9, respectively.
¨
ments and M. Taublander for contributing to synthetic experi-
ments. B. Holzer, E. Horkel and C. Hametner are acknowledged
for performing NMR experiments.
In conclusion, we have established a straightforward, cheap
and reliable synthesis of versatile building blocks 6a–c on a
(multi)gram-scale. The application of the developed building
blocks potentially yields functional organic materials with entirely
new properties compared to widely applied 1,4-bis[(trimethylsilyl)-
ethynyl]-2,5-bis(hexyloxy)benzene (X = O). Thus, microwave-
assisted CuAAC polymerization of 6a and post-polymerization
modification were demonstrated. The observed alteration in
photophysical properties by this simple oxidation procedure
utilizing DMDO gives rise to several possible applications
ranging from color tuning to post-processing modification of
polymer layers.
Notes and references
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Experimental section
General procedure for the synthesis of 6a–c
5 (1.0 eq.) was dissolved in degassed dry Et2O (0.1 M) under an
argon atmosphere in a pressure resistant glass vial. The solution
was cooled to À78 1C and t-BuLi (1.7 M in pentane, 4.0 eq.) was
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À78 1C before allowing the solution to warm above 0 1C. Sulfur,
selenium or dihexyltelluride (2.1 eq.) was then added and the
yellow suspension was stirred for 3 h at room temperature/60 1C.
If elemental reagents were used, hexyl iodide (2.2 eq.) was addi-
tionally added and the suspension was stirred at 60 1C overnight.
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Microwave-assisted CuAAC polymerization
´
˜
´
Dialkyne 6a (1.0 eq.) and diazide 7 (1.0 eq.) were weighed in 14 P. Lopez-Alvarado, C. Avendano and J. C. Menendez, Synth.
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¨
¨
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18 See ESI† for details.
Post-polymerization modification
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Int. Ed., 2009, 48, 48–58.
2232 | New J. Chem., 2014, 38, 2229--2232
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