Ethyl acetate

Ethyl acetate (systematically ethyl ethanoate, commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula CH
3−COO−CH
2−CH
3, simplified to C
4H
8O
2. This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues, nail polish removers, and in the decaffeination process of tea and coffee. Ethyl acetate is the ester of ethanol and acetic acid; it is manufactured on a large scale for use as a solvent.[4]

Ethyl acetate
Names
Preferred IUPAC name
Ethyl acetate
Systematic IUPAC name
Ethyl ethanoate
Other names
  • Acetic ester
  • Acetic ether
  • Ethyl ester of acetic acid
Identifiers
3D model (JSmol)
506104
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.005.001
E number E1504 (additional chemicals)
26306
KEGG
RTECS number
  • AH5425000
UNII
Properties
C4H8O2
Molar mass 88.106 g·mol−1
Appearance Colorless liquid
Odor Ether-like, fruity[1]
Density 0.902 g/cm3
Melting point −83.6 °C (−118.5 °F; 189.6 K)
Boiling point 77.1 °C (170.8 °F; 350.2 K)
8.3 g/100 mL (at 20 °C)
Solubility in ethanol, acetone, diethyl ether, benzene Miscible
log P 0.71[2]
Vapor pressure 73 mmHg (9.7 kPa) at 20 °C[1]
Acidity (pKa) 25
−54.10×10−6 cm3/mol
1.3720
Viscosity 426 μPa·s (0.426 cP) at 25 °C
Structure
1.78 D
Hazards
Main hazards
  • Flammable (F),
  • Irritant (Xi)
Safety data sheet See: data page
R-phrases (outdated) R11, R36, R66, R67
S-phrases (outdated) S16, S26, S33
NFPA 704 (fire diamond)
Flammability code 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineHealth code 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
1
0
Flash point −4 °C (25 °F; 269 K)
Explosive limits 2.0–11.5%[1]
Lethal dose or concentration (LD, LC):
11.3 g/kg, rat
16,000 ppm (rat, 6 h)
12,295 ppm (mouse, 2 h)
1600 ppm (rat, 8 h)[3]
21 ppm (guinea pig, 1 h)
12,330 ppm (mouse, 3 h)[3]
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 400 ppm (1400 mg/m3)[1]
REL (Recommended)
 TWA 400 ppm (1400 mg/m3)[1]
IDLH (Immediate danger)
 2000 ppm[1]
Related compounds
Related carboxylate esters
Related compounds
Supplementary data page
Refractive index (n),
Dielectric constant (εr), etc.
Thermodynamic
data
 Phase behaviour
solid–liquid–gas
UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

Production

In 2004, an estimated 1.3 million tonnes were produced worldwide.[4][5] The combined annual production in 1985 of Japan, North America, and Europe was about 400,000 tonnes. The global ethyl acetate market was valued at $3.3 billion in 2018.[6]

Ethyl acetate is synthesized in industry mainly via the classic Fischer esterification reaction of ethanol and acetic acid. This mixture converts to the ester in about 65% yield at room temperature:

CH
3CO
2H + CH
3CH
2OH → CH
3CO
2CH
2CH
3 + H
2O

The reaction can be accelerated by acid catalysis and the equilibrium can be shifted to the right by removal of water.

It is also prepared in industry using the Tishchenko reaction, by combining two equivalents of acetaldehyde in the presence of an alkoxide catalyst:

2 CH
3CHO → CH
3CO
2CH
2CH
3

Silicotungstic acid is used to manufacture ethyl acetate by the alkylation of acetic acid by ethylene:[7]

C
2H
4 + CH
3CO
2H → CH
3CO
2C
2H
5


Uses

Ethyl acetate is used primarily as a solvent and diluent, being favored because of its low cost, low toxicity, and agreeable odor.[8] For example, it is commonly used to clean circuit boards and in some nail varnish removers (acetone is also used). Coffee beans and tea leaves are decaffeinated with this solvent.[9] It is also used in paints as an activator or hardener. Ethyl acetate is present in confectionery, perfumes, and fruits. In perfumes, it evaporates quickly, leaving only the scent of the perfume on the skin.

Laboratory uses

In the laboratory, mixtures containing ethyl acetate are commonly used in column chromatography and extractions.[10] Ethyl acetate is rarely selected as a reaction solvent because it is prone to hydrolysis, transesterification, and condensations.

Occurrence in wines

Ethyl acetate is the most common ester in wine, being the product of the most common volatile organic acid – acetic acid, and the ethyl alcohol generated during the fermentation. The aroma of ethyl acetate is most vivid in younger wines and contributes towards the general perception of "fruitiness" in the wine. Sensitivity varies, with most people having a perception threshold around 120 mg/L. Excessive amounts of ethyl acetate are considered a wine fault.

Reactions

Ethyl acetate is a Lewis base that forms 1:1 adducts with a variety of Lewis acid such as I2, phenol, and bis(hexafloroacetylacetonato)copper(II). It is classified as a hard base and is a base in the ECW model yielding EB =1.62 and CB = 0.98.

Ethyl acetate hydrolyses to give acetic acid and ethanol. Bases accelerate the hydrolysis, which is subject to the Fischer equilibrium mentioned above. In the laboratory, and usually for illustrative purposes only, ethyl esters are typically hydrolyzed in a two-step process starting with a stoichiometric amount of a strong base, such as sodium hydroxide. This reaction gives ethanol and sodium acetate, which is unreactive toward ethanol:

CH
3CO
2C
2H
5 + NaOH → C
2H
5OH + CH
3CO
2Na

Under anhydrous conditions, strong bases induce the Claisen condensation to give ethyl acetoacetate:[11]

Preparation of ethyl acetoacetate.

Safety

The LD50 for rats is 5620 mg/kg,[12] indicating low toxicity. Given that the chemical is naturally present in many organisms, there is little risk of toxicity.

In the field of entomology, ethyl acetate is an effective asphyxiant for use in insect collecting and study. In a killing jar charged with ethyl acetate, the vapors will kill the collected insect quickly without destroying it. Because it is not hygroscopic, ethyl acetate also keeps the insect soft enough to allow proper mounting suitable for a collection.

Overexposure to ethyl acetate may cause irritation of the eyes, nose, and throat. Severe overexposure may cause weakness, drowsiness, and unconsciousness.[13] Humans exposed to a concentration of 400 ppm in 1.4 mg/L ethyl acetate for a short time were affected by nose and throat irritation.[14] Ethyl acetate is an irritant of the conjunctiva and mucous membrane of the respiratory tract. Animal experiments have shown that, at very high concentrations, the ester has central nervous system depressant and lethal effects; at concentrations of 20,000 to 43,000 ppm (2.0–4.3%), there may be pulmonary edema with hemorrhages, symptoms of central nervous system depression, secondary anemia and liver damage. In humans, concentrations of 400 ppm cause irritation of the nose and pharynx; cases have also been known of irritation of the conjunctiva with temporary opacity of the cornea. In rare cases exposure may cause sensitization of the mucous membrane and eruptions of the skin. The irritant effect of ethyl acetate is weaker than that of propyl acetate or butyl acetate.[15]

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References
  1. NIOSH Pocket Guide to Chemical Hazards. "#0260". National Institute for Occupational Safety and Health (NIOSH).
  2. "ethyl acetate MSDS".
  3. "Ethyl acetate". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. Riemenschneider, Wilhelm; Bolt, Hermann M. "Esters, Organic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a09_565.pub2.
  5. Dutia, Pankaj (August 10, 2004). "Ethyl Acetate: A Techno-Commercial Profile" (PDF). Chemical Weekly: 184. Retrieved 2009-03-21.
  6. ""Global Ethyl Acetate Market to be valued at $3.3 billion in 2018" reports Visiongain". Visiongain. 2019-09-05. Retrieved 2019-09-05.
  7. Misono, Makoto (2009). "Recent progress in the practical applications of heteropolyacid and perovskite catalysts: Catalytic technology for the sustainable society". Catalysis Today. 144 (3–4): 285–291. doi:10.1016/j.cattod.2008.10.054.
  8. Data,https://www.reportsanddata.com, Reports and. "Ethyl Acetate Market Share 2019 | Industry Report, 2027". www.reportsanddata.com. Retrieved 2020-02-04.
  9. ico.org Archived 2007-04-29 at the Wayback Machine
  10. Tan, Wei Wen; Wu, Bin; Wei, Ye; Yoshikai, Naohiko (2018). "Copper and Secondary Amine-Catalyzed Pyridine Synthesis from O-Acetyl Oximes and α,β-Unsaturated Aldehydes". Organic Syntheses. 95: 1–14. doi:10.15227/orgsyn.095.0001.
  11. Inglis, J. K. H.; Roberts, K. C. (1926). "Ethyl Acetoacetate". Org. Synth. 6: 36. doi:10.15227/orgsyn.006.0036.
  12. Hazard Ethyl Acetate MSDS "Ethyl Acetate MSDS Number: E2850".
  13. Mackison, F. W.; Stricoff, R. S.; Partridge, L. J., Jr., eds. (Jan 1981). NIOSH/OSHA – Occupational Health Guidelines for Chemical Hazards. DHHS (NIOSH) Publication No. 81–123. Washington, DC: U.S. Government Printing Office.
  14. Clayton, G.D.; Clayton, F.E., eds. (1993–94). Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology (4th ed.). New York, NY: John Wiley & Sons. p. 2981.
  15. Encyclopedia of Occupational Health and Safety, Geneva, Switzerland: International Labour Office, 1983, p. 782
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