Carbyne

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In chemistry, a carbyne is a monovalent carbon radical species. It occurs in several ways.

Contents

[edit] Gas phase

  • A carbene can occur as a short-lived reactive intermediate. For instance, fluoromethylidyne (CF) can be detected in the gas phase by spectroscopy as an intermediate in the flash photolysis of CHFBr2. [1]

[edit] Organometallic

  • Carbynes are incorporated in metal carbyne complexes.[1] Details of their reactivity and that of the related carbenes is shown at [2]. For example in [WBr(CO)2(2,2'-bipyridine)C-Aryl] and [WBr(CO)2(PPh3)2C-NR2]. An example of how to make such a compound would be to react [W(CO)6] with Lithium diisopropylamide to form [(iPr2N)(OLi)C=W(CO)5]. This is then reacted with either oxalyl bromide or Br-Br-PPh3 followed by triphenyl phosphine.

Another method is to treat a methoxy metal carbene with a lewis acid.[3]

[edit] Form of carbon

  • Carbyne is also the name for the carbon allotrope that has the chemical structure [2] -(C:::C)n- .Carbon in this modification is linear with sp orbital hybridisation, and is a polymer with alternating single and triple bonds. This type of carbyne is of considerable interest to nanotechnology.

[edit] References

  • [1] Chemistry of carbynes: reaction of CF, CCl, and CBr with alkenes B. P. Ruzsicska, A. Jodhan, H. K. J. Choi, O. P. Strausz, T. N. Bell; J. Am. Chem. Soc.; 1983; 105(8); 2489-2490.
  • [2] Carbyne and Carbynoid Structures Series: Physics and Chemistry of Materials with Low-Dimensional Structures, Vol. 21 Heimann, R.B.; Evsyukov, S.E.; Kavan, L. (Eds.) 1999, 452 p., Hardcover ISBN 0-7923-5323-4