Lignoceric acid

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Structural formula
Structural formula of lignoceric acid
General
Surname Lignoceric acid
other names
  • Tetracontanoic acid
  • n -Tetracosanoic acid
  • Carnaubic acid ( obsolete )
Molecular formula C 24 H 48 O 2
Brief description

colorless solid

External identifiers / databases
CAS number 557-59-5
EC number 209-180-7
ECHA InfoCard 100.008.347
PubChem 11197
Wikidata Q422634
properties
Molar mass 368.65 g mol −1
Physical state

firmly

density

0.8207 g cm −3 (100  ° C )

Melting point

82 ° C; 81.5-84.5 ° C

boiling point

272 ° C (10 torr)

solubility
  • practically insoluble in water
  • easily soluble in benzene and diethyl ether
Refractive index

1.4287 (100 ° C)

safety instructions
GHS labeling of hazardous substances
07 - Warning

Caution

H and P phrases H: 315-319-335
P: 261-305 + 351 + 338
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Lignoceric acid ( n- tetracosanoic acid) is a chemical compound from the group of saturated higher fatty acids . It belongs to the subgroup of wax acids . Their salts and esters are called lignocerates (systematically also tetracosanoates .)

Occurrence

Lignoceric acid is found in tall oil , a by-product of lignin production , and in wood tar . It is also contained in the triglycerides of peanut oil and in many other vegetable oils as an ester; it occurs in this form in many plant species. Carnauba wax contains esters of lignoceric acid.

properties

Lignoceric acid is a solid with a melting point of approx. 82–84 ° C and it is practically insoluble in water.

The reduction of lignoceric acid leads to lignoceryl alcohol .

Outdated designation

Carnaubic acid is also found in the literature (24: 0), but the constitution is indefinite, whereas the melting point of 72.5 ° C seems to be roughly clear. It is sometimes equated with the isomer, lignoceric acid (24: 0), but this is unlikely due to the vastly different melting point. It seems very likely that the carnaubic acid is not a fatty acid in its own right, but samples of lignoceric acid which are contaminated with other acids.

Individual evidence

  1. ↑ a b c d Data sheet Lignoceric acid, ≥99% (capillary GC) from Sigma-Aldrich , accessed on February 19, 2013 ( PDF ).
  2. ↑ a b c d e David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 95th edition. (Internet version: 2015), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-498.
  3. ^ Albin H. Warth: The Chemistry and Technology of Waxes. Second Edition, Reinhold Publ., 1956, p. 34, online at babel.hathitrust.org, accessed November 1, 2017.
  4. ^ DJ Anneken, S. Both, R. Christoph, G. Fieg, U. Steinberner, A. Westfechtel: Fatty Acids. In: Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH, Weinheim, 2006, doi : 10.1002 / 14356007.a10_245.pub2 .
  5. ^ A b Walter Karrer : Constitution and occurrence of organic plant substances. Springer, 1958, ISBN 978-3-0348-6808-2 (reprint), p. 295.
  6. ↑ Tetracosanoic acid at PlantFA Database, accessed November 2, 2017.
  7. ^ Ullmann's Food and Feed. Vol. 1, Wiley, 2017, ISBN 978-3-527-33990-7 , p. 655.
  8. ^ Albin H. Warth: The Chemistry and Technology of Waxes. Second Edition, Reinhold Publ., 1956, p. 35, online at babel.hathitrust.org, accessed November 1, 2017.
  9. ↑ Emil Abderhalden (Ed.): Biochemisches Handlexikon. 1st volume, 2nd half, Springer, 1911, ISBN 978-3-642-88963-9 , p. 1018.

Web links

Wiktionary: Tetracosanoic acid  - explanations of meanings, word origins, synonyms, translations