ch3coochch2

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Vinyl acetate
Skeletal formula
Ball-and-stick model
Names
Preferred IUPAC name

Ethenyl acetate

Systematic IUPAC name

Ethenyl ethanoate

Other names
  • Acetic acid vinyl ester
  • Vinyl ethanoate
  • Acetoxyethene
  • VyAc
  • VAM
  • Vinyl acetate monomer
  • Acetic acid ethenyl ester
  • 1-Acetoxyethylene
Identifiers

CAS Number

  • 108-05-4 check

3D model (JSmol)

  • Interactive image

Beilstein Reference

1209327
ChEBI
  • CHEBI:46916 check
ChemSpider
  • 7616 check
ECHA InfoCard 100.003.224 Edit this at Wikidata
EC Number
  • 203-545-4
KEGG
  • C19309 check
MeSH C011566

PubChem CID

  • 7904
UNII
  • L9MK238N77 ☒

CompTox Dashboard (EPA)

  • DTXSID3021431 Edit this at Wikidata

InChI

  • InChI=1S/C4H6O2/c1-3-6-4(2)5/h3H,1H2,2H3 ☒

    Key: XTXRWKRVRITETP-UHFFFAOYSA-N ☒

  • InChI=1/C4H6O2/c1-3-6-4(2)5/h3H,1H2,2H3

    Key: XTXRWKRVRITETP-UHFFFAOYAB

SMILES

  • C=COC(C)=O

Properties

Chemical formula

C4H6O2
Molar mass 86.090 g·mol−1
Appearance Colorless liquid
Odor Sweet, pleasant, fruity; may be sharp and irritating[1]
Density 0.934 g/cm3
Melting point −93.5 °C (−136.3 °F; 179.7 K)
Boiling point 72.7 °C (162.9 °F; 345.8 K)

Magnetic susceptibility (χ)

−46.4×10−6 cm3/mol
Hazards
GHS labelling:

Pictograms

GHS02: FlammableGHS07: Exclamation markGHS08: Health hazard

Signal word

Danger

Hazard statements

H225, H332, H335, H351

Precautionary statements

P201, P202, P210, P233, P240, P241, P242, P243, P261, P271, P280, P281, P303+P361+P353, P304+P312, P304+P340, P308+P313, P312, P370+P378, P403+P233, P403+P235, P405, P501
NFPA 704 (fire diamond)
Flash point −8 °C (18 °F; 265 K)

Autoignition
temperature

427 °C (801 °F; 700 K)
Explosive limits 2.6–13.40%
NIOSH (US health exposure limits):

PEL (Permissible)

none[2]
Safety data sheet (SDS) ICSC 0347

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

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Infobox references

Vinyl acetate is an organic compound with the formula CH3CO2CH=CH2. This colorless liquid is the precursor to lớn polyvinyl acetate, ethene-vinyl acetate copolymers, polyvinyl alcohol, and other important industrial polymers.[3]

Production[edit]

The worldwide production capacity of vinyl acetate was estimated at 6,969,000 tonnes/year in 2007, with most capacity concentrated in the United States (1,585,000 all in Texas), Trung Quốc (1,261,000), nhật bản (725,000) and Taiwan (650,000).[4] The average list price for 2008 was US$1600/tonne. Celanese is the largest producer (ca 25% of the worldwide capacity), while other significant producers include Trung Quốc Petrochemical Corporation (7%), Chang Chun Group (6%), and LyondellBasell (5%).[4]

It is a key ingredient in furniture glue.[5]

Preparation[edit]

Vinyl acetate is the acetate ester of vinyl alcohol. Since vinyl alcohol is highly unstable (with respect to lớn acetaldehyde), the preparation of vinyl acetate is more complex kêu ca the synthesis of other acetate esters.

The major industrial route involves the reaction of ethylene and acetic acid with oxygen in the presence of a palladium catalyst.[6]

This method has replaced the addition of acetic acid to lớn acetylene. The main side reaction is the combustion of organic precursors.

Mechanism[edit]

Isotope labeling and kinetics experiments suggest that the mechanism involves PdCH2CH2OAc-containing intermediates. Beta-hydride elimination would generate vinyl acetate and a palladium hydride, which would be oxidized to lớn give hydroxide.[7]

Alternative routes[edit]

Vinyl acetate was once mainly prepared by hydroesterification, i.e., the addition of acetic acid to lớn acetylene in the presence of metal catalysts. Using mercury(II) catalysts, vinyl acetate was first prepared by Fritz Klatte in 1912.[3] Presently, zinc acetate is used as the catalyst:

CH3CO2H + C2H2 → CH3CO2CHCH2

Approximately 1/3 of the world's production relies on this route, which, because it is environmentally messy, is mainly practiced in countries with relaxed environmental regulations, such as Trung Quốc.

Another route to lớn vinyl acetate involves thermal decomposition of ethylidene diacetate:

(CH3CO2)2CHCH3 → CH3CO2CHCH2 + CH3CO2H

Polymerization[edit]

It can be polymerized to lớn give polyvinyl acetate (PVAc). With other monomers it can be used to lớn prepare various copolymers such as ethylene-vinyl acetate (EVA), vinyl acetate-acrylic acid (VA/AA), polyvinyl chloride acetate (PVCA), and polyvinylpyrrolidone (Vp/Va copolymer, used in hair gels).[8] Due to lớn the instability of the radical, attempts to lớn control the polymerization by most "living/controlled" radical processes have proved problematic. However, RAFT (or more specifically, MADIX) polymerization offers a convenient method of controlling the synthesis of PVA by the addition of a xanthate or a dithiocarbamate chain transfer agent.

Other reactions[edit]

Vinyl acetate is useful in organic synthesis.[9] Transacetylation is used to lớn obtain enantioenriched alcohols and esters. Iridium-catalyzed transacetylation have also been demonstrated:[10][11]

ROH + CH2=CHOAc → ROCH=CH2 + HOAc

Transvinylation is also possible using vinyl acetate. It undergoes Diels-Alder reactions with dienes.

Vinyl acetate undergoes many of the reactions anticipated for an alkene and an ester. Bromine adds to lớn give the dibromide. Hydrogen halides add to lớn give 1-haloethyl acetates, which cannot be generated by other methods because of the non-availability of the corresponding halo-alcohols. Acetic acid adds in the presence of palladium catalysts to lớn give ethylidene diacetate, CH3CH(OAc)2. It undergoes transesterification with a variety of carboxylic acids.[12] The alkene also undergoes Diels–Alder and 2+2 cycloadditions.

Toxicity evaluation[edit]

Tests suggest that vinyl acetate has low toxicity. Oral LD50 for rats is 2920 mg/kg.[3]

On January 31, 2009, the Government of Canada's final assessment concluded that exposure to lớn vinyl acetate is not harmful to lớn human health.[13] This decision under the Canadian Environmental Protection Act (CEPA) was based on new information received during the public comment period, as well as more recent information from the risk assessment conducted by the European Union.

In the context of large-scale release into the environment, it is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), under which it "does not meet toxicity criteria[,] but because of its acute lethality, high production volume [or] known risk is considered a chemical of concern". By this law, it is subject to lớn strict reporting requirements by facilities that produce, store, or use it in quantities greater kêu ca 1000 pounds.[14]

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See also[edit]

  • Polyvinyl alcohol
  • Vinyl propionate

References[edit]

  1. ^ "Public Health Statement for Vinyl Acetate". Agency for Toxic Substances and Disease Registry, Centers for Disease Control. It has a sweet, pleasant, fruity smell, but the odor may be sharp and irritating to lớn some people.
  2. ^ NIOSH Pocket Guide to lớn Chemical Hazards. "#0656". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ a b c Bienewald, Frank; Leibold, Edgar; Tužina, Pavel; Roscher, Günter (2019). "Vinyl Esters". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. pp. 1–16. doi:10.1002/14356007.a27_419.pub2.
  4. ^ a b H. Chinn (September 2008). "CEH Marketing Research Report: Vinyl Acetate". Chemical Economics Handbook. SRI consulting. Retrieved 2011-07-01.[dead link]
  5. ^ Karl Shmavonian (2012-10-24). "Madhukar Parekh's Pidilite Industries Earns His Family $1.36 Billion". Forbes.com. Retrieved 27 January 2013. though Pidilite has had to lớn contend with the rising price of vinyl acetate monomer, its key raw material
  6. ^ Y.-F. Han; D. Kumar; C. Sivadinarayana & D. W. Goodman (2004). "Kinetics of Ethylene Combustion in the Synthesis of Vinyl Acetate over a Pd/SiO2 Catalyst" (PDF). Journal of Catalysis. 224: 60–68. doi:10.1016/j.jcat.2004.02.028.
  7. ^ Stacchiola, D.; Calaza, F.; Burkholder, L.; Schwabacher Alan, W.; Neurock, M.; Tysoe Wilfred, T. (2005). "Elucidation of the Reaction Mechanism for the Palladium‐Catalyzed Synthesis of Vinyl Acetate". Angewandte Chemie International Edition. 44 (29): 4572–4574. doi:10.1002/anie.200500782. PMID 15988776.
  8. ^ "VP/VA Copolymer". Personal Care Products Council. Archived from the original on 16 October 2012. Retrieved 13 December 2012.
  9. ^ Manchand, Percy S. (2001). "Vinyl Acetate". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rv008. ISBN 0471936235.
  10. ^ Tomotaka Hirabayashi, Satoshi Sakaguchi, Yasutaka Ishii (2005). "Iridium-catalyzed Synthesis of Vinyl Ethers from Alcohols and Vinyl Acetate". Org. Synth. 82: 55. doi:10.15227/orgsyn.082.0055.{{cite journal}}: CS1 maint: uses authors parameter (link)
  11. ^ Yasushi Obora, Yasutaka Ishii (2012). "Discussion Addendum: Iridium-catalyzed Synthesis of Vinyl Ethers from Alcohols and Vinyl Acetate". Org. Synth. 89: 307. doi:10.15227/orgsyn.089.0307.{{cite journal}}: CS1 maint: uses authors parameter (link)
  12. ^ D. Swern & E. F. Jordan, Jr. (1963). "Vinyl Laurate and Other Vinyl Esters" (PDF). Organic Syntheses, Collected Volume. 4: 977. Archived from the original (PDF) on 2011-06-05. Retrieved 2007-11-11.
  13. ^ "Summary of Public Comments Received on the Government of Canada's Draft Screening Assessment Report on Vinyl Acetate (CAS No. 108-05-4)" (PDF). Health Canada. 2009.
  14. ^ "40 C.F.R: Appendix A to lớn Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities" (PDF). Code of Federal Regulations (December 2017 ed.). Government Printing Office. title 40, vol. 30, part 355, ứng dụng. A (EPA): 474. December 2017. Retrieved 7 March 2018 – via US GPO.

External links[edit]

  • EPA health assessment information on vinyl acetate
  • CDC - NIOSH Pocket Guide to lớn Chemical Hazards
  • Summary of risk assessment by the Government of Canada