Acetic acid sec- pentyl ester

Structural formula
	Simplified structural formula without stereochemistry
General
Surname	Acetic acid sec- pentyl ester
other names	Pentan-2-ylacetate ( IUPAC ); 2-pentyl ethanoate; sec-amyl acetate; 1-methylbutyl acetate; 2-pentyl acetate; Ethanoic acid 2-pentyl ester;
Molecular formula	C 7 H 14 O 2
Brief description	colorless liquid
External identifiers / databases
EC number	210-946-8
ECHA InfoCard	100,009,952
PubChem	12278
ChemSpider	11775
Wikidata	Q2180922
properties
Molar mass	130.19 g mol −1
Physical state	liquid
density	0.86 g cm −3 (20 ° C)
Melting point	−78.5 ° C
boiling point	134 ° C
Vapor pressure	9.3 h Pa (20 ° C); 14.7 hPa (30 ° C); 25.5 hPa (40 ° C); 42.4 hPa (50 ° C);
solubility	practically insoluble in water; soluble in ethanol and diethyl ether ;
safety instructions
GHS hazard labeling from Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary Caution
H and P phrases	H: 226
	EUH: 066
	P: ?
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Acetic acid sec- pentyl ester (according to IUPAC nomenclature : pentan-2-ylacetate , systematically also 2-pentyl ethanoate ) is an organochemical compound from the group of carboxylic acid esters .

Isomerism

2-Pentyl acetate occurs in two enantiomeric forms , since it has a center of chirality on the C2 carbon of the preceding alcohol . Thus, there exist ( R ) -2-pentyl acetate and ( S ) -2-pentyl acetate. A 1: 1 mixture of the two enantiomers is called a racemate .

(R) -2-pentyl acetate
(S) -2-pentyl acetate

Extraction and presentation

Racemic acetic acid sec- pentyl ester is produced on an industrial scale by acid-catalyzed esterification of acetic acid with 2-pentanol .

According to the principle of Le Chatelier , separation of the water produced or the removal of the ester shifts the equilibrium to the product side (see also the law of mass action ).

properties

Physical Properties

Acetic acid sec- pentyl ester has a relative gas density of 4.49 (density ratio to dry air at the same temperature and pressure) and a relative density of the steam-air mixture of 1.03 (density ratio to dry air at 20 ° C and normal pressure ). In addition, 2-pentyl acetate has a vapor pressure of 9.3 hPa at 20 ° C, 14.7 hPa at 30 ° C, 25.5 hPa at 40 ° C and 42.4 hPa at 50 ° C.

Chemical properties

Acetic acid sec- pentyl ester is a flammable liquid belonging to the group of carboxylic acid esters , which is practically insoluble in water and lighter than it. 2-Pentyl acetate is of medium or low volatility. When heated up, thermal decomposition occurs and acetic acid and hydrocarbons are formed as products. Dangerous chemical reactions ( explosions ) can occur with strong oxidizing agents .

use

Acetic acid sec- pentyl ester is mainly sold as a mixture of the other pentyl acetates . Together with the isomeric compounds, it is mainly used as a solvent in the production of coating materials based on cellulose nitrate . Pentyl acetates dissolve natural resins such as copal , dammar , elain, kauri , waxes , some alkyd resins and especially cellulose esters . They are also used to manufacture smokeless explosives and serve as solvents in chromatography in the laboratory. In the past, the Hefner candle was used as a light standard that used amyl acetate (= acetic acid sec- pentyl ester) or a mixture of pentyl ester of acetic acid as fuel .

safety instructions

The vapors of 2-pentyl acetate can form explosive mixtures with air when heated above the flash point. This is possible even at higher ambient temperatures . Acetic acid sec- pentyl ester is mainly absorbed via the respiratory tract . This leads to acute irritation to the respiratory tract and eyes ; at high concentrations, a disruption of the central nervous system is to be expected. Chronic skin changes and irritative effects on the mucous membranes often occur . No meaningful tests have been carried out on reproductive toxicity , mutagenicity and carcinogenicity , but test results for the isomeric pentyl acetates do not assume a carcinogenic or mutagenic effect. 2-Pentyl acetate has a lower explosion limit (LEL) of 1.0% by volume and an upper explosion limit (UEL) of 7.5% by volume. The ignition temperature is 390 ° C. The substance therefore falls into temperature class T2 and explosion group IIA. With a flash point of 32 ° C, 2-pentyl acetate is considered flammable.

Web links

Commons : sec-pentyl acetate - Collection of images, videos and audio files

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m Entry on 1-methylbutyl acetate in the GESTIS substance database of the IFA , accessed on April 21, 2019 (JavaScript required)
↑ ^a ^b Entry on 2-pentyl acetate in the Hazardous Substances Data Bank , accessed April 21, 2019.
↑ Entry on 1-methylbutyl acetate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on April 21, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .
^ Entry on pentylacetate. In: Römpp Online . Georg Thieme Verlag, accessed on April 21, 2019.
^ H. Lux: The modern lighting system , accessed on April 21, 2019

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m Entry on 1-methylbutyl acetate in the GESTIS substance database of the IFA , accessed on April 21, 2019 (JavaScript required)

[HSDB-2] Entry on 2-pentyl acetate in the Hazardous Substances Data Bank , accessed April 21, 2019.

[CLP_100.009.952-3] Entry on 1-methylbutyl acetate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on April 21, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .

[RÖMPP-4] Entry on pentylacetate. In: Römpp Online . Georg Thieme Verlag, accessed on April 21, 2019.

[5] H. Lux: The modern lighting system , accessed on April 21, 2019