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| Names | |||
|---|---|---|---|
| Preferred IUPAC name Methyl prop-2-enoate[1] | |||
| Other names | |||
| Identifiers | |||
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3D model (JSmol) | |||
| ChEMBL | |||
| ChemSpider |
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| ECHA InfoCard | 100.002.274 | ||
| KEGG |
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| UNII | |||
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| Properties | |||
| C4H6O2 | |||
| Molar mass | 86.090 g·mol−1 | ||
| Appearance | Colorless liquid | ||
| Odor | Acrid[2] | ||
| Density | 0.95 g/cm3[3] | ||
| Melting point | −74 °C (−101 °F; 199 K)[3] | ||
| Boiling point | 80 °C (176 °F; 353 K)[3] | ||
| 5 g/100 mL | |||
| Vapor pressure | 65 mmHg (20°C)[2] | ||
| Viscosity | |||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards | Harmful (Xn); Highly flammable (F+) | ||
| Flash point | −3 °C (27 °F; 270 K)[3] | ||
| Explosive limits | 2.8–25%[2] | ||
| Lethal dose or concentration (LD, LC): | |||
LC50 (median concentration) | 3575 ppm (mouse) 1350 ppm (rat, 4 hr) 1000 ppm (rat, 4 hr) 2522 ppm (rabbit, 1 hr)[5] | ||
| NIOSH (US health exposure limits): | |||
PEL (Permissible) | TWA 10 ppm (35 mg/m3) [skin][2] | ||
REL (Recommended) | TWA 10 ppm (35 mg/m3) [skin][2] | ||
IDLH (Immediate danger) | 250 ppm[2] | ||
| Safety data sheet (SDS) | Oxford MSDS | ||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Methyl acrylate is anorganic compound, more accurately themethyl ester ofacrylic acid. It is a colourless liquid with a characteristic acrid odor. It is mainly produced to makeacrylate fiber, which is used to weave synthetic carpets.[6] It is also areagent in the synthesis of various pharmaceutical intermediates. Owing to the tendency of methyl acrylate to polymerize, samples typically contain an inhibitor such ashydroquinone.
The standard industrial reaction for producing methyl acrylate isesterification of acrylic acid withmethanol under acid catalysis (sulfuric acid,p-toluenesulfonic acid or acidic ion exchangers.[7]). The transesterification is facilitated because methanol and methyl acrylate form a low boilingazeotrope (boiling point 62–63 °C).[8]
The patent literature[9] describes a one-pot route involving vapor-phase oxidation of propene or 2-propenal with oxygen in the presence of methanol.
Methyl acrylate can be prepared bydebromination of methyl 2,3-dibromopropanoate withzinc.[10] Methyl acrylate is formed in goodyield onpyrolysis ofmethyl lactate in the presence ofethenone (ketene).[11] Methyl lactate is a renewable "green chemical". Another patent[12] describes the dehydration of methyl lactate overzeolites.
The nickel tetracarbonyl-catalyzedhydrocarboxylation of acetylene with carbon monoxide in the presence of methanol also yields methyl acrylate.[13] The reaction of methyl formate with acetylene in the presence of transition metal catalysts also leads to methyl acrylate.[14] Both, the alcoholysis of propiolactone with methanol as well as the methanolysis of acrylonitrile via intermediately formed acrylamide sulfate[15] are also proven but obsolete processes.
Methyl acrylate is afterbutyl acrylate andethyl acrylate the third most important acrylic ester with a worldwide annual production of about 200,000 tons in 2007.[16] Poly(methyl acrylate) is a tacky material near room temperature, and as such it is not particularly useful as a structural material. Commonly, methyl acrylate (and other acrylate esters) arecopolymerized with other alkenes to give useful engineering plastics.[17] A variety ofvinyl monomers are used, includingstyrene and other acrylates.[18] The resulting copolymers give acrylic paints that are harder and morebrittle than those with the homologous acrylates. Copolymerizing methyl acrylate with acrylonitrile improves their melt processability to fibers, which could be used as precursors for carbon fibers.[19] Methyl acrylate is the precursor to fibers that are woven to make carpets.
Methyl acrylate reacts catalysed byLewis bases in aMichael addition withamines in high yields to β-alanine derivatives which provide amphoteric surfactants when long-chain amines are used and the ester function is hydrolysed subsequently.
Acrylates are also used in the preparation ofpoly(amidoamine) (PAMAM)dendrimers typically by Michael addition with a primaryamine.
Methyl acrylate is used for the preparation of2-dimethylaminoethyl acrylate by transesterification withdimethylaminoethanol in significant quantities of over 50,000 tons / year.[20]
Methyl acrylate is a classic Michael acceptor, which means that it adds nucleophiles at its terminus. For example, in the presence of a base catalyst, it adds hydrogen sulfide to give the thioether:[21]
It is also a gooddienophile.
It is an acute toxin with anLD50 (rats, oral) of 300 mg/kg and aTLV of 10 ppm.
