Synthesis of Monocyanopolyynes and Dicyanopolyynes with the Submerged Electric Arc - Polyynes: Synthesis, Properties, and Applications - page 329

and remain unchanged for much longer time in comparison to mono-
cyanopolyynes.
Dicyanopolyynes series can be easily produced by arcing graphite
electrodes into liquid nitrogen. C 6 N 2 ,C 8 N 2 ,andC 10 N 2 have been easily
trapped into solvents where the vaporized liquid nitrogen is bubbled and
detected by liquid chromatography. This approach may lead to an easier
route to almost pure dicyanopolyynes.
The formation of dicyanopolyynes is accompanied by the formation of
small amounts of hydrogen-terminated polyynes whose formation is due to
the presence of water humidity in the experimental system adopted.
Also, the dicyanopolyynes are unstable in an acetonitrile solution at
room temperature and after 1 day storage they disappear completely.
ACKNOWLEDGMENTS
ASI, the Italian Space Agency, is gratefully acknowledged for the financial
support of this work under the grant I/R/070/02.
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