- Atomic carbon
.
This very short lived species is created by passing a large current through two adjacent carbon rods, generating an electric arc. Atomic carbon is generated in the process. Professor
Phil Shevlin has done the principal work in the field based atAuburn University in the USA.The way this species is made is closely related to the formation of fullerenes
C60 , the chief difference being that a much lower vacuum is used in atomic carbon formation.This species has been used to generate "true"
carbenes by the abstraction ofoxygen atoms fromcarbonyl groups:: R2C=O + :C: → R2C: + CO
Carbenes formed in this way will exhibit true carbenic behaviour. Carbenes prepared by other methods such as diazocompounds, might exhibit properties better attributed to the diazocompound used to make the carbene (which mimic carbene behaviour), rather than to the carbene itself. This is important from a mechanistic understanding of true carbene behaviour perspective.
References
*cite journal
title = Images of atomic carbon in the interstellar medium
author = White G. J., Padman R.
journal =Nature
year = 1991
volume = 354
issue =
pages = 511–513
doi = 10.1038/354511a0*cite journal
title = Formation of Atomic Carbon in the Decomposition of 5-tetrazoyldiazonium Chloride
author = P. B. Shevlin
journal =J. Amer. Chem. Soc.
year = 1972
volume = 94
issue =
pages = 1397
doi = 10.1021/ja00759a069* P. B. Shevlin, "The Preparation and Reaction of Atomic Carbon" in Reactive Intermediates, Vol. 1 R. A. Abramovitch Ed. Plenum Press. New York, 1980, p. 1.
*cite journal
title = An Experimental and Theoretical Investigation of the Mechanism of Deoxygenation of Carbonyl Compounds by Atomic Carbon
author = M. J. S. Dewar, D. J. Nelson, P. B. Shevlin, K. A. Biesida
journal =J. Amer. Chem. Soc.
year = 1981
volume = 103
issue =
pages = 2802
doi = 10.1021/ja00400a052* K. A. Biesiada and P. B. Shevlin "The Intramolecular Trapping of an Intermediate in the Deoxygenation of a Carbonyl Compound by Atomic Carbon" "
J. Org. Chem. " 1984, 49, 1151. doi|10.1021/jo00180a047
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