Pinene

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Pinene
Pinene
IUPAC name Pinene
Identifiers
CAS number [* 80-56-8 (unspecified)
  • 7785-70-8 (1R-alpha)
  • 7785-26-4 (1S-alpha)
  • 2437-95-8 ((+-)-alpha)
  • 18172-67-3 (beta)]
Properties
Molecular formula C10H16
Molar mass 136.24 g/mol
Appearance Liquid
Density 0,86 g·cm−3 (alpha, 15 °C)[1][2]
Melting point

−62–−55 °C (alpha)[1]
Boiling point

155–156 °C (alpha)[1]
Solubility in water Practically insoluble in water
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references

The chemical compound pinene is a bicyclic terpene (C10H16, 136.24 g/mol ) known as a monoterpene [1]. There are two structural isomers found in nature: α-pinene and β-pinene. As the name suggests, both forms are important constituents of pine resin; they are also found in the resins of many other conifers, and more widely in other plants. Both are also used by many insects in their chemical communication system.

Systematic names are (1S,5S)-2,6,6-trimethylbicyclo[3.1.1]hept-2-ene and (1S,5S)-6,6-dimethyl-2-methylenebicyclo[3.1.1]heptane.

Contents

[edit] Isomers

skeletal formula
ball-and-stick model
name
(+)-α-pinene
(−)-α-pinene
(+)-β-pinene
(−)-β-pinene

[edit] Biosynthesis

α-Pinene and β-pinene are both produced from geranyl pyrophosphate, via cyclisation of linaloyl pyrophosphate followed by loss of a proton from the carbocation equivalent.

Biosynthesis of pinene from geranyl pyrophosphate

[edit] Usage

Selective oxidation of pinene with some catalysts in chemical industry give many components for pharmacy, artificial odorants and so on. The primary oxidation product is verbenone.

Pinene left verbenone right

It can form by simple air oxidation but a synthetic method employs lead tetraacetate [2].

Pinenes form the primary constituents of turpentine.

[edit] References

  1. ^ a b c Record of alpha-Pinen in the GESTIS Substance Database from the BGIA, accessed on {{{Date}}}
  2. ^ Record of beta-Pinen in the GESTIS Substance Database from the BGIA, accessed on {{{Date}}}
  1. ^  J. Mann, R. S. Davidson, J. B. Hobbs, D. V. Banthorpe, J. B. Harborne, Natural Products, pp309-311, Addison Wesley Longman Ltd., Harlow, UK, 1994. ISBN 0-582-06009-5.
  2. ^  Organic Syntheses, Coll. Vol. 9, p.745 (1998); Vol. 72, p.57 (1995). Article

[edit] External links