Chemistry:Quaternary carbon

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Short description: A carbon atom bound to four other carbon atoms
quaternary carbon
Neopentan (Quartäre Kohlenstoffatome) V1.svg
Structural formula of neopentane (quaternary carbon is highlighted red)

A quaternary carbon is a carbon atom bound to four other carbon atoms.[1] For this reason, quaternary carbon atoms are found only in hydrocarbons having at least five carbon atoms. Quaternary carbon atoms can occur in branched alkanes, but not in linear alkanes.[2]

primary carbon secondary carbon tertiary carbon quaternary carbon
General structure
(R = Organyl group)
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Partial
Structural formula
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Synthesis

The formation of chiral quaternary carbon centers has been a synthetic challenge. Chemists have developed asymmetric Diels–Alder reactions,[3] Heck reaction, Enyne cyclization, cycloaddition reactions,[4] C–H activation, Allylic substitution, [5] Pauson–Khand reaction, [6] etc. to construct asymmetric quaternary carbon atoms.

References

  1. Smith, Janice Gorzynski (2011). "Chapter 4 Alkanes" (in en) (Book). Organic chemistry (3rd ed.). New York, NY: McGraw-Hill. p. 116. ISBN 978-0-07-337562-5. http://highered.mheducation.com/sites/007340277x/student_view0/index.html. Retrieved 2018-06-26. 
  2. Hans Peter Latscha, Uli Kazmaier, Helmut Alfons Klein (2016) (in German), Organische Chemie: Chemie-Basiswissen II (7. Auflage ed.), Berlin: Springer Spektrum, p. 40, ISBN 978-3-662-46180-8 
  3. Nicolaou, K. C.; Vassilikogiannakis, G.; Mägerlein, W.; Kranich, R Angew. Chem. Int. Ed. Volume 2001, Issue 40 , Pages 2482–2486 {{DOI: 10.1002/1521-3773(20010702)40:13<2482::AID-ANIE2482>3.0.CO;2-A}}
  4. Quasdorf, K.W.; Overman, L. E. Nature Volume 2014, Volume 516, Pages 181 {{doi:10.1038/nature14007}}
  5. "Allylic Substitution for Construction of a Chiral Quaternary Carbon Possessing an Aryl Group". J. Org. Chem. 78 (8): 3755–3766. 2013. doi:10.1021/jo400248y. PMID 23496084. 
  6. Ishizaki, M.; Niimi, Y.; Hoshino, O.; Hara, H.; Takahashi, T. Tetrahedron Volume 2001, Issue 61, Pages 4053–4065