Isopentyl acetate

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Structural formula
Structural formula of isopentyl acetate
General
Surname Isopentyl acetate
other names
  • Acetic acid (3-methylbutyl) ester
  • 3-methylbutyl acetate
  • Isoamyl acetate
  • i -amylacetate
  • Pear oil
  • Pear ether
  • i -pentyl acetate
  • 3-methyl-1-butyl acetate
  • ISOAMYL ACETATE ( INCI )
Molecular formula C 7 H 14 O 2
Brief description

Not very volatile, colorless liquid with a fruity / banana-like odor

External identifiers / databases
CAS number 123-92-2
EC number 204-662-3
ECHA InfoCard 100.004.240
PubChem 31276
Wikidata Q221307
properties
Molar mass 130.19 g mol −1
Physical state

liquid

density

0.87 g cm −3

Melting point

−79 ° C

boiling point

142 ° C

Vapor pressure
  • 5.3 h Pa (20 ° C)
  • 10 hPa (30 ° C)
  • 33 hPa (50 ° C)
solubility

slightly soluble in water (2.12 g l −1 at 19.4 ° C)

Refractive index

1,400 (20 ° C)

safety instructions
GHS labeling of hazardous substances
02 - Highly / extremely flammable

Caution

H and P phrases H: 226
EUH: 066
P: 210
Toxicological data
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

Isopentyl acetate is a chemical compound from the group of carboxylic acid esters , more precisely pentyl acetate .

Occurrence

Isopentyl acetate is one of the main components of banana flavor and an important flavoring agent in beer . It has also been detected as a flavoring substance in a variety of other fruits and other foods, especially fermented drinks. Bees release the compound before an attack, so it's an alarm pheromone.

Extraction and presentation

Isopentyl acetate ( 2 ) can be obtained by esterifying isoamyl alcohol ( 1 ) with acetic acid:

Acid-catalyzed synthesis of isoamyl acetate

This acid-catalyzed equilibrium reaction can be shifted to the side of the ester 2 in that the water formed is removed from the reaction mixture.

properties

Isopentyl acetate is a slightly volatile, flammable, colorless liquid with a fruity odor that is sparingly soluble in water.

Safety-related parameters

Isopentyl acetate forms highly flammable vapor-air mixtures. The compound has a flash point of 35 ° C. The explosion range is between 1% by volume (53 g / m 3 ) as the lower explosion limit (LEL) and 9% by volume (485 g / m 3 ) as the upper explosion limit (UEL). The lower explosion point is 33 ° C. The ignition temperature is 380 ° C. The substance therefore falls into temperature class T2.

use

Isopentyl acetate is used as a banana aroma because of its banana smell. In the past, the Hefner candle was used as a light standard, using iso-amyl acetate = isopentyl acetate or a mixture of pentyl ester of acetic acid as fuel. In addition, because of its strong smell, it is also used for leak testing of military gas protective masks.

Individual evidence

  1. Entry on ISOAMYL ACETATE in the CosIng database of the EU Commission, accessed on March 21, 2020.
  2. a b c d e f g h i j k l m n o p q r Entry for CAS no. 123-92-2 in the GESTIS substance database of the IFA , accessed on September 21, 2018(JavaScript required) .
  3. Data sheet Isoamyl acetate, natural, ≥97%, FCC, FG from Sigma-Aldrich , accessed on September 20, 2015 ( PDF ).
  4. ^ Marshall J. Myers, Phillip Issenberg, Emily L. Wick: l-Leucine as a precursor of isoamyl alcohol and isoamyl acetate, volatile aroma constituents of banana fruit discs. In: Phytochemistry. 9, 1970, p. 1693, doi : 10.1016 / S0031-9422 (00) 85580-6 .
  5. Prof. Dr. Werner Back: Microbiology of Food Volume 5: Beverages . Behr's Verlag DE, 2008, ISBN 978-3-89947-956-0 , p. 144 ( limited preview in Google Book search).
  6. Entry on isopentyl acetate. In: Römpp Online . Georg Thieme Verlag, accessed on September 21, 2015.
  7. a b Jeff Potter: Cooking for Geeks Inspiration & Innovation for the Kitchen; [Recipes and Scientific Adventures] . O'Reilly Germany, 2011, ISBN 978-3-86899-125-3 , pp. 96 ( limited preview in Google Book search).
  8. ^ Hermann Sahm, Garabed Antranikian, Klaus-Peter Stahmann, Ralf Takors: Industrial microbiology . Springer-Verlag, 2014, ISBN 978-3-8274-3040-3 , pp. 265 ( limited preview in Google Book search).
  9. ^ A b E. Brandes, W. Möller: Safety-related parameters - Volume 1: Flammable liquids and gases , Wirtschaftsverlag NW - Verlag für neue Wissenschaft GmbH, Bremerhaven 2003.
  10. H. Lux, Modern Lighting, accessed on November 28, 2018.
  11. ^ Occupational Safety and Health Administration: Fit Testing Procedures (Mandatory). - 1910.134 App A | Occupational Safety and Health Administration , accessed January 17, 2020.