Any organic compound with alternating C–C and C≡C bonds
A polyyne is any organic compound with alternating single and triple bonds; that is, a series of consecutive alkynes, (−C≡C−)n with n greater than 1. These compounds are also called polyacetylenes, especially in the natural products and chemical ecology literature,[1] even though this nomenclature more properly refers to acetylene polymers composed of alternating single and double bonds (−CR=CR′−)n with n greater than 1. They are also sometimes referred to as oligoynes,[2][needs IPA] or carbinoids after "carbyne" (−C≡C−)∞, the hypothetical allotrope of carbon that would be the ultimate member of the series.[3][4] The synthesis of this substance has been claimed several times since the 1960s, but those reports have been disputed.[5] Indeed, the substances identified as short chains of "carbyne" in many early organic synthesis attempts[6] would be called polyynes today.
The simplest polyyne is diacetylene or butadiyne, H−C≡C−C≡C−H. Along with cumulenes, polyynes are distinguished from other organic chains by their rigidity and high conductivity,[7] both of which make them promising as wires in molecular nanotechnology. Polyynes have been detected in interstellar molecular clouds where hydrogen is scarce.[citation needed]
^Cite error: The named reference Blacklock2008 was invoked but never defined (see the help page).
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Gibtner, Thomas; Hampel, Frank; Gisselbrecht, Jean-Paul; Hirsch, Andreas (2002). "End-cap stabilized oligoynes: Model compounds for the linear sp carbon allotrope carbyne". Chemistry: A European Journal. 8 (2): 408–432. doi:10.1002/1521-3765(20020118)8:2<408::AID-CHEM408>3.0.CO;2-L. PMID11843154.
^Heimann, R.B.; Evsyukov, S.E.; Kavan, L., eds. (1999). Carbyne and carbynoid structures. Physics and Chemistry of Materials with Low-Dimensional Structures. Vol. 21. p. 452. ISBN978-0-7923-5323-2.